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Science / Space Race

[August 26, 1968] No time for a breath (Summer space round-up)

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by Gideon Marcus

There are some months where the space shots come so quickly that there's scarcely time to apprehend them all, much less report on them!  Every other day, it seems, the newspaper has got a headling about this launch or that discovery, and that's before you get to the announcements about the impending moon missions.

So, in rapid-fire style, let's see how many exciting new missions I can tell you about on a single exhale (while you stand on one leg, no less…that's a Jewish joke).

A Pair of Yankee Explorers

On August 8th, a Scout rocket took off from Vandenberg Air Force Base (the Western Test Range) in Southern California carrying the two latest NASA science satellites.  It was a virtual duplicate of the launch nearly four years ago of Explorers 24 and 25: a balloon for measuring air density in the upper atmosphere, and a more conventional satellite with an array of instruments for surveying the Earth's ionosphere.  Affectionately dubbed "Mutt and Jeff", these two craft were sent into polar orbit (hence the Pacific launch site).  If you're wondering why NASA is repeating itself, that's because the sun has a profound effect on the Earth's atmosphere.  It is important to measure its impact throughout the 11 year solar cycle, from minimum to maximum output, to better understand the relationship between the solar wind and the air's upper layers.

Not much can go wrong with a balloon, but Explorer 40, after deploying its spindly experiment arms, suffered a malfunction.  Its solar panels are not delivering as much power as they should.  NASA is confident, however, that this will not compromise the mission, which is planned to last more than a year.

Alphabet Soup

Time was, we gave proper names to our satellites.  Now it's all acronyms and arcane jumbles of letters and numbers.  That's all right.  I can decipher them for you!

Advanced Technology Satellite (ATS) 4

August 10 marked the launch of "Daddy Longlegs" ATS 4, the fourth of seven satellites in this series.

Some of you may remember ATS-1–you may recall that ATS-1 helped relay the first worldwide "Our World" broadcast last year. 

ATS-1 is actually still working, just like its two siblings.  ATS-2, launched April 5, 1967 was judged a failure since the second stage of its carrier rocket malfunctioned, stranding it in an eccentric orbit.  Still, the several science experiments onboard have returned information on cosmic rays and such in space.  ATS-3, which went up November 5, 1967, was the last to ride an Atlas Agena D rocket.  Armed with a panoply of experiments, including two transceivers, two cameras, and a host of radiation detectors, that satellite worked perfectly, returning the first color picture of the entire Earth!

ATS-4, unlike its predecessors, is a strictly practical spacecraft, carrying no science experiments, but makes up for it in engineering marvels.  One is a a day-night Image Orthicon Camera, a teevee transmitter that would provide continuous color coverage of the world from high up in geosynchronous orbit (i.e. orbiting at the same rate as the Earth turns, keeping it more or less stationary with respect to the ground).  Another is a microwave transmitter, turning ATS into a powerful communications satellite like its progenitor

ATS-4 also was to test out a gravity gradient stabilization system, basically using the subtle gradations of the Earth's pull on the satellite's arms to keep it oriented in orbit.  Finally, ATS-4 has an ion engine aboard.  These drives, perfect for space, work by shooting out Cesium electrons.  They are incredibly economical compared to conventional rockets, but their thrust is quite low, meaning they must be fired continuously to have an appreciable effect on velocity.

Sadly, as with ATS-2, ATS-4's Atlas Centaur failed on the second stage, stranding the satellite in a low, largely useless orbit.  Well, I guess that's why you launch lots of them!

ESSA 7

We haven't given the ESSA series of satellites much love, which I suppose is what happens when a technology stops being novel and instead becomes routine, even essential.  After all, who reports on every airplane that takes off anymore?

But it's worth talking about the latest satellite, ESSA 7, launched August 16, to summarize what the system has done for us over the last several years.

There were eleven satellites in the TIROS series of weather craft, the first launched in 1960.  In February 1966, with the launch of ESSA 1, the Environmental Science Services Administration (ESSA) took over the cartwheel satellites, making the series officially operational.

All of them have worked perfectly, launched into sun-synchronous polar orbits about 900 miles up that circle the Earth from north to south as the planet rotates eastward beneath.  So perfect is ESSA 7's orbit that it will cross the equator at virtually the same time every day, drifting from that time table by only four minutes every year.

ESSA satellites have returned 3000 warnings of hurricanes, typhoons, and cyclones, reporting not just on the existence but the intensity of these dangerous storms.  As of May 27 of this year, ESSA satellites had taken a million photos of the Earth's weather–that's $42 per picture, since the total launch cost of an ESSA is $6 million.


An image of Tropical Storm Shirley taken August 19, 1968

Up in the Kosmos

If we had to cover the launch of every Kosmos (Cosmos) satellite out of the Soviet Union, we'd have to go to a daily schedule.  There's such a thing as too much of a good thing, right?

But the Russkies are putting them up on the average of one a week, so it's worth sampling them occasionally to keep tabs on all the stuff they're putting in orbit.  Especially since the Kosmos is a catch-all designator, even more broad than our Explorer series.  It includes military satellites, science satellites, weather satellites, even automatic tests of the Soyuz spacecraft.

Here's a brief outline of the launches this last month:

Kosmos 230

This is a typical Soviet launch press release:

The Soviet Union launched another Cosmos satellite today and the Sputnik was reported functioning normally, Tass, the official Soviet news agency, said.  The device, Cosmos 230, is sending information to a Soviet research center for evaluation.

We know it was launched July 5 into a 48.5 degree inclined orbit, that it soars between 181 and 362 miles above the Earth, and that it's still in orbit as we speak, circling the Earth every 92.8 minutes.

As for what it's for… well, your guess is as good as mine.  That said, it's probably not a spy satellite.  How do I know?  Read on, and I'll show you what a spy sat looks like so you can spot them yourself!

Kosmos 231

The Soviet Union has launched another satellite in its program of exploring outer space, the official Tass news agency said Thursday.  It said Cosmos 231 was launched Wednesday [July 10] and is functioning normally.  The latest Cosmos is orbiting the earth once every 89.7 minutes in a low orbit from 130 miles to 205 miles.  Its angle to the earth was 65 degrees.

Seems innocuous enough, right?  Doesn't tell you anything more than the other one.  Except…

First tip-off: the angle.  A zero degree angle would be along the equator, never leaving 0 degrees latitude.  A 90 degree angle is polar, heading due north and south.  The lower the angle, the narrower a band of the Earth a satellite covers.

A 65 degree angle is sufficient to cover a wide swathe…including all of the continental United States.

The altitude is quite low, too.  The closer, the better–if you want to look at something from orbit.

But the real kicker is this: the spacecraft reentered on July 18, just eight days after launch.  Normally, when you send a science satellite up, you want it to stay in orbit as long as possible to get more back for your buck…er…ruble.  You only deorbit a spacecraft (and make no mistake–Kosmos 231 had to have been deorbited; its orbit wasn't that low) when there's something onboard you want to get back.  Like a person…or film.

We know there wasn't anyone onboard Kosmos 231.  The Soviets would have told us.  By the way, I'm not the only one who thinks the Kosmos was a spy satellite, taking pictures in orbit and then landing the film for processing.  There's a blurb in the July 15th issue of Aviation Weekly and Space Report which says the same thing.  And they reached that conclusion before the craft even landed, just based on the orbit!

By the way, if you're wondering what the Soviet spy satellites look like, we actually have a better idea of theirs than ours!  We're pretty sure they're based on the Vostok space capsules used to carry cosmonauts.  In fact, it's an open question whether or not the spy sat was evolved from the Vostok or the other way around!

Kosmos 232

Launched July 16, its orbital parameters were as follows: 125 to 220 miles in altitude, 89.8 minute orbit, 65 degree inclination.  The newspaper article I read noted that the satellite's path was a common one, and predicted the satellite would be recovered in eight days.

Sure enough, it was on the ground again on July 24.

Sound familiar?

Kosmos 233

Here's another oddball: launched on the 18th, the Soviets didn't release news of its orbiting until at least the 20th.  It's in a near polar orbit, soaring up to 935 miles, grazing the Earth with a perigee of 124 miles.

That's no spy sat.  In fact, I'd guess this one might be a bonafide science satellite, exploring the Earth's Van Allen Belts.  But it could just as easily be the equivalent of our Transit navigational satellites or something.  We won't know until and unless the Communists publish scientific results.

Kosmos 234

Launched July 30, it soared from 130 to 183 miles up with a period of 89.5 minutes and an inclination of 51.8 degrees.  Low orbit?  Check.  Cryptic announcement describing its purpose as "the continued exploration of outer space"?  Check.  But the inclination's a bit low.  Better wait for more information.

Oh wait.  It landed August 5.  Pretty sure we know what this one was!

Kosmos 235

Up August 9, down August 17.  Orbit went from 126 to 176 miles, period was 89.3 minutes, and the inclination was exactly the same as before–51.8 degrees.

I'm not sure the significance of the different inclinations.  Maybe it's a matter of the rocket or the launch location.  Generally, the higher the inclination, the more expensive the shot in terms of fuel since the rocket doesn't get the extra boost of the Earth's rotation.

Operator?

It's been a while since we covered the Molniya communications satellites, one of the few Soviet series we do know something about.  July 5 marked the launch of the ninth comsat in the series, zooming up to a high, not quite geosynchronous, orbit, where it has a nice vantage of the whole of Asia.

This launch comes less than three months after the orbiting of Molniya H, the eighth in the series.  Whether Molniya I is replacing its predecessor, which may have been faulty, or whether the ninth Molniya is simply acting as a backup, is not certain.  The latter seems unlikely, though.  When Molniya G went up just three weeks after Molniya F, it was widely believed that the Russians had sent up two to make sure they could televise their annual November Moscow parade to the other Communist countries.

That's all folks!

That's the big news for this month.  The rest of the year is going to be really exciting, what with the upcoming launch of Apollo 7 and Zond 5.  We're about to enter a new phase of manned lunar exploration.  That said, we promise to keep covering the significant shots closer to home, too.  For us, all space missions are out of this world!


The prime crew for Apollo 7 (l-r) Astronauts Donn F. Eisele, Command Module Pilot; Walter Cunningham, Lunar Module Pilot; and Walter M. Schirra, Jr., Commander




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Science / Space Race

[July 16, 1968] Hitching a Ride to Orbit (Orbiting Vehicle Satellite Series)

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by Kaye Dee

The continuing hiatus in American and Soviet manned spaceflight and the present lack of unmanned lunar and interplanetary missions, has been a blessing as well as a disappointment. It's given us an opportunity to focus on some lesser-known US and USSR space programmes that are quietly going about their business largely unreported. One such is the US Air Force’s Orbiting Vehicle programme, which saw its most recent launch just a few days ago. While the Traveller has previously taken a look at some early OV1 series missions, the whole thing is worth looking at–it's really quite exciting!

Hitching a Ride on an ICBM
When the Air Force Office of Aerospace Research (OAR) was looking for a means to conduct space experiments at the lowest possible cost, it conceived the idea of using small satellites of a standardised design, launched as secondary payloads piggybacking on Atlas ICBMs being flown for missile technology development. After all, Atlas vehicles have been used to launch satellites as far back as 1958 (Project SCORE), as well as launching all the orbital missions of NASA’s Mercury programme.

This concept led to the development of Orbiting Vehicle (OV) programme, initially created in the early 1960s under the name SATAR (SATellite for Atmospheric Research). SATAR was an extension of the "Scientific Passenger Pods" (SPP) flown as external payloads on suborbital Atlas missile tests to conduct scientific experiments during their brief time in space. In its original form, SATAR was to use a larger version of the SPP, called the Atlas Retained Structure (ARS), that would carry a small satellite with its own propulsion system. When the Atlas missile reached its apogee, the satellite would be deployed from the ARS, using its propulsion system for orbital insertion.

Renamed the Orbiting Vehicle programme around 1963, this project now includes five separate series of standardised satellites, designated OV1 through OV5, each designed for a specific research goal.

OV1-3 launches in a side pod on an Atlas missile ABRES test flight

Launching OV1
The first series of OV satellites – which has seen the greatest number of launches to date – is OV1, developed by the Convair Division of General Dynamics, which also produces the Atlas vehicle. Initially, OV1 satellites were going to be launched on Atlas missiles testing nosecones for the Advanced Ballistic Re-Entry System (ABRES). However, only OV1-1 and OV1-3 ever flew piggyback on an ABRES mission, mounted in pods on the side of the missile. Both satellites were, unfortunately, unsuccessful.

View of the OV1-2 launch showing the twin top-mounted pods. Although there were two pods, only a single satellite was launched on this flight

The other OV1 missions so far have been launched on dedicated Atlas D and F boosters (retired from the ICBM programme) purchased by the OAR for the OV1 series. These flights use two modified SPP pods mounted side-by-side on top of the Atlas, enabling two satellites to be launched on each OV1 flight. The only exceptions to date have been OV1-6, which flew on the Manned Orbiting Laboratory test flight on 2 November 1966, and OV1-86, carried in a side-mounted pod on the same launch that lofted OV1-11 and OV1-12.

Small but Versatile
Using a standardised satellite design has enabled experiments to move rapidly from proposal to launch, the process taking just fifteen months on average. The operational design of the multi-purpose OV1 spacecraft is a cylinder 4 ft 6.6 in long and 2 ft 3 in in diameter, with a cap on both ends covered with 5000 solar cells producing 22 Watts of power. The satellite is attached to a discardable propulsion module using an Altair 2 solid-fuelled motor for orbital insertion. It has two 1 ft 6 in antennae for command and telemetry, with attitude control provided by hydrogen peroxide thrusters. The use of a Sun sensor to determine the spacecraft's orientation to the Sun commenced with OV1-7, while OV1-13 and OV1-14 introduced advanced digital telemetry, which has improved the data return from the satellites. OV1-1 undergoing a balance test prior to launch

Since the launch of OV1-1, on 21 January(GMT) 1965, 17 OV1 series satellites have so far been launched, with more apparently on the way. Only five have failed in some way. The basic purpose of this series is research into fundamental properties of the upper atmosphere and the space environment. This has meant that, unlike the experiments and results from most USAF satellites (and other OV series), which remain classified, the details of OV1 experiments have been published. But will we ever find out how closely the OV1 missions are related to the classified programs?

OV1 Highlights
Notable missions of the OV1 series so far have included OV1-4, launched 30 March (GMT) 1966, which carried three Tissue Equivalent Ionization Chambers, similar to one flown on Gemini 4, NASA’s first spacewalk mission. This data has helped to quantify the radiation hazard that astronauts face on long-duration missions in orbit.

OV1-6, launched on a Titan IIIC with the Manned Orbiting Laboratory test flight in November 1966, uniquely carried several inflatable balloons. Once ejected into orbit, they served as optical targets for ground-based observations, apparently to determine the value of inflatable decoys in confusing anti-missile systems.

PasComSat , or OV1-8, was launched on 14 July (GMT) 1966 and used for passive communications tests, designed to compare the advantages of a grid-sphere satellite against a balloon similar to the Echo series. Its non-standard design comprised a 30ft diameter open spherical grid of soft aluminium wires embedded in an inflatable plastic balloon. The entire satellite, with its unique propulsion module, weighed just 23lb. The satellite’s structure was also intended to demonstrate the feasibility of erecting an open grid structure in space, as the polybutyl methacrylate plastic of the balloon was designed to break down after a few days under the sun's strong ultraviolet rays, leaving the open aluminium structure in orbit. Tests indicate that the grid-satellite will remain in orbit for at least 11 years and have measured its reflective power as five times greater than that of a solid sphere.

OV1-9, launched in December 1966, carried a number of radiation experiments and was still aloft in late May 1967, during an intense period of solar and magnetic activity. Its data proved the existence of the Earth's electric field, which had long been theorised. OV1-10, OV1-9’s launch twin, returned the most comprehensive set of solar X-ray observations to date and also carried a cosmic ray telescope.

A unique “triple launch” took place on 27 July (GMT) 1967, with OV1-86 flying in a side-mounted pod and OV1-11 and OV1-12 positioned on top of the Atlas D launch vehicle. OV1-86 was an opportunistic mission composed of the unused satellite body originally intended as OV1-8, coupled with the unused OV1-6 propulsion module, which was not required for its Titan IIIC launch. The satellite carried a cosmic ray telescope, as well as equipment measuring the temperature radiation properties of different types of Earth terrain, mapping the Earth in the near-infrared spectrum. Although OV1-11 failed to orbit, OV1-12 carried the Flare Activated Radio-biological Observatory, equipped with a suite of eleven experiments to study the radiation hazard from solar flares.

The first Atlas F launch of the OV1 series placed OV1-13 and OV1-14 in orbit on 6 April (GMT) 1968. Both satellites were designed to focus on measuring radiation in space, although OV-14 ceased operating after one week in service. OV1-13 recently measured increases in the energy and intensity of electrons during a geomagnetic storm that took place 10 June 1968, and it is hoped that its data will shed light on how the particle flow caused by solar storms creates these high altitude increases. OV1-14


Spades and Cannonballs
The most recent OV1 launch took place on 11 July, carrying both a standard satellite and the second non-standard spacecraft in this series. OV1-15 has a suite of experiments developed by The Aerospace Corporation designed to study the response of the upper atmosphere to solar and magnetospheric disturbances. It is hoped that the Solar Perturbation of Atmospheric Density Experiments Satellite (SPADES) group of complementary experiments will help to identify the cause of large and sudden fluctuations encountered in satellite trajectories, he ultimate goal being an ability to predict these fluctuations and their magnitude. OV1-16 is another non-standard satellite, also known as LOADS (LOw Altitude Density Satellite) and Cannon Ball. This unique satellite is designed to have a large a mass/area ratio, so that they can remain in orbit at lower altitudes than conventional satellite, enabling measurements of the atmospheric properties at around 65-90miles altitude. This lower thermosphere region is a largely unknown part of the atmosphere. Cannon Ball lives up to its nickname, as a sphere with a diameter of only 24 inches, although its total weight is 600 lb, largely due to a 1.5 inch thick shell of brass! Concerns about heating by sunlight and atmospheric heating caused by orbiting at low altitude meant that the satellite body has been painted black (to increase radiation) with some gold-plated circular areas. If this experiment goes well, there may be further OV satellites of this type.

Unlucky So Far!
The OV2 series could be considered the “unluckiest” of the Orbiting Vehicle projects to date. Out of four flights, two have failed and two were canceled! The series was originally devised within the ARENTS (Advanced Research Environmental Test Satellite) programme, with the satellites intended to complement the Vela programme, monitoring for violations of the 1963 Partial Test Ban Treaty. However, with the cancellation of ARENTS, OV2 became something of an “orphan” series, its initial three satellites each tasked with quite different research.

OV2-1 shortly before launch, with its experiment package labelled

OV2-1, launched 15 October (GMT) 1965, was intended to monitor the biological hazards of near Earth charged particles, but failed to separate from its launcher. OV2-2, planned to conduct optical measurements from orbit, was cancelled, as was the OV2-4 satellite, added to the programme and designed to observe radiation from trans-lunar orbit. OV2-3, intended to undertake radiation studies, failed when contact was lost after launch on 21 December (GMT) 1965. A fifth OV2 satellite has been authorised and is due for launch later this year to conduct astronomical research and radiation studies. Produced by Northrop and launched on Titan III test flights, the spin-stabilised OV2 satellites had cubic bodies made of aluminium honeycomb, approximately 2ft on a side. Attached to each of the four upper corners of the satellite are 7ft 6in paddle-like solar panels each carrying 20,160 solar cells, although the satellites also have Nickel-Cadmium to operate while in the Earth’s shadow.

Taking a Scout
In a departure from the earlier series, OV3 satellites have all been launched on Scout boosters, used with many civilian satellite programmes, such as the Explorer series. OV3-1 to OV3-4 were built by the Space General Corporation (part of Aerojet), while OV3-5 and 6 were constructed by the Air Force Cambridge Research Laboratory (AFCRL), which also managed the entire series.

Octagonal prisms in shape, the first four OV3 satellites were 2ft 5in in length and the same dimensions wide, with their experiments carried on long booms. With a design life-span of one year, the satellites were covered with 2560 solar cells. OV3-5 and OV3-6 were a little smaller than their predecessors, being only 1ft 9in in length.

The initial group of OV3-1 to 4 were devoted to radiation studies and launched across 1966. OV3-2 made important charged particle observations in conjunction with the 12 November 1966 South American solar eclipse that was also observed by Gemini 12. Other observations and auroral research were also co-ordinated with airborne observations by AFCRL KC-135 aircraft and sounding rocket flights by the National Research Council of Canada.

VLF receiver data from OV3-3 determined the location of the plasmapause (the outer boundary of the Earth's inner magnetosphere), while the satellite also carried out radiation studies using the same suite of instruments as the failed OV2-1. OV3-4 data contributed to the refinement of theoretical models of astronaut radiation dosage.

The final two OV3 missions, in 1967, were focussed on ionospheric research. While OV3-5 failed to achieve orbit, OV3-6, launched 5 December (GMT) 1967 was quite successful. Also known as Atmospheric Composition Satellite (ATCOS)-2, its data is being used to create more accurate atmospheric models.

Despite keeping costs low by using off-the-shelf components, the OV3 programme was phased out after OV3-6, in favour of the cheaper OV1 programme.

Whispering Galleries
Just as particular physical conditions create the “whispering gallery” phenomenon under the dome of a building, the OV4 series satellites was initially created to investigate long range radio propagation in the charged atmosphere of the ionosphere. Each OV4 launch was intended to consist of a pair of satellites, one being the transmitting spacecraft, the other a receiver. However, only the OV4-1 mission was flown in this way with the OV4-2 pair cancelled. OV4-1R and OV4-1T shortly before launch

The OV4-1 satellite pair were both cylindrical, 1ft 5in in diameter, with domed upper ends. 2ft 11in long, they were powered by silver oxide/zinc batteries which gave them a 50-day lifespan.

Launched on a Manned Orbiting Laboratory (MOL) test flight on 3 November (GMT) 1966, OV4-1T carried a transmitter broadcasting on three frequencies in the 20-50 MHz range. To maximise its orbital separation from the OV4-1R receiver satellite, OV4-1T incorporated a small rocket motor. The two satellites were launched into slightly different 190-mile orbits, allowing them to test “whispering gallery” communications over a range of distances. This enabled the OV4-1 satellites to evaluate using the ionosphere's F layer as way to facilitate HF and VHF transmissions between satellites not in line of sight of each other.

Apart from being designated as part of the OV4 series, OV4-3 launched on the same Titan III flight as the OV4-1 pair, was a quite different spacecraft, being the boiler plate model of the Manned Orbiting Laboratory. The reconditioned Gemini 2 (originally flown on a sub-orbital flight on 19 January 1965), was attached to the MOL model. Little Stars
The most recent of the Orbiting Vehicle programme to date, with the smallest satellites, the OV5 series is a continuation of the Air Force's earlier Environmental Research Satellite (ERS) series. OV5 satellites are upgraded versions of the original ERS satellites developed by Space Technology Laboratories (part of TRW Inc), modified with a command receiver, allowing instructions to be sent from the ground, and advanced digital telemetry.
Spin-stabilized, for improved communications and solar power reliability, OV5 series satellites are tetrahedral in shape and made of aluminium struts. Just under 1ft in width, each satellite carries 816 solar cells distributed over its eight triangular faces. Power is stored in a nickel–cadmium battery and experiments are mounted on the vertices of the tetrahedron.

Passive thermal control keeps the inside of the spacecraft at around 59 °F, and an on-board timer is designed to shut off each satellite after 18 months of operation. Telemetry is broadcast on frequencies compatible with NASA Spacecraft Tracking and Data Acquisition Network (STADAN) stations, enabling the satellite data to be received at multiple locations.

The first two OV5 satellites, OV5-1 and OV5-3 were launched on 28 April (GMT) 1967 on a Titan IIIC vehicle. OV5-1, also known as ERS 27 is an X-ray measuring microsatellite associated with the US Air Force's “space weather” prediction programme. OV5-3, also known as ERS 28, is a materials science research project, carrying a variety of metal samples and Teflon, to investigate how they are affected by long-term exposure to the space environment. OV5-2, another materials science research experiment, is due to be launched later this year.

While the Orbiting Vehicle programme has developed somewhat differently from the original concept, insofar as it has largely transitioned away from hitchhiking on various test launches, the OV1, 3 and 5 series satellites have demonstrated the value of using standardised designs as a means for cheap and relatively rapid development and launch of space research instruments. The OV1 and OV5 programmes look set to continue for some years to come and will hopefully contribute further significant data towards our understanding of the space environment. 

So, here's to "micro" satellites–perhaps they presage the future of cheap space development!

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Science / Space Race

[June 28, 1968] Classified Communications (IDCSP Satellite Constellation)

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by Kaye Dee

An advantage of previously working for the Weapons Research Establishment in South Australia is that I am still able to get information (of the unclassified variety, of course) about defence space programmes from my former colleagues. This is particularly helpful when I’m writing about space projects that are not getting a large amount of press coverage here in Australia.


One such project is the Initial Defence Communication Satellite Programme (IDCSP), the United States’ first global military communications network. The most recent IDCSP launch took place on 13 June with the launch of eight satellites on a Titan IIIC rocket, bringing the total number of satellites in the constellation to 27.

The Advent of Defence Satellite Communications
The very first experimental communications satellites were created by the U.S. armed forces. Project SCORE was jointly developed by the U.S. Air Force and communications company RCA, while the first active repeater comsat, Courier 1-B, was developed by the U.S. Army Signal Corps. I think we can be sure that these early satellites satisfactorily carried out classified experiments in secure defence communications, as the first planned military satellite communications network, Project ADVENT, commenced development in February 1960.

Diagram of the proposed ADVENT satellite in orbit

ADVENT intended to place several large, three-axis stabilised, heavy satellites in geosynchronous orbit (with one of its ground stations planned to be located in the Australian Trust Territory of Papua New Guinea). However, this extremely ambitious programme soon fell behind schedule and saw costs balloon out to twice the original estimates, leading to its cancellation in 1962. It’s perhaps not surprising that the ADVENT programme faced difficulties in developing its satellites – even six years later, an operational three-axis stabilised satellite has yet to become reality.

The engineering test vehicle for the ADVENT satellites under construction

Enter IDCSP
Following ADVENT’s cancellation, the U.S. Air Force embarked on a new satellite communications system as a replacement. Originally called the Interim Defence Communications Satellite Programme, it has since been renamed as the Initial Defence Communications Satellite Programme. IDCSP is intended to be the first stage in the longer-term Defence Communications Satellite Program (DCSP), which is being managed by the Defence Communications Agency.

Commenced in 1962, the IDCSP is designed to be significantly cheaper than ADVENT by using a constellation of small, much simpler satellites. The original plan was for a constellation of 24-30 satellites, placed into Medium Earth Orbit using ten Atlas Agena rockets. In October 1963, the programme was placed on hold while the Pentagon investigated renting satellite communications capability through the INTELSAT system, but this idea was abandoned in mid-1964 and Air Force resumed work on the IDCSP.

Doing the Heavy Lifting
As it happened, the delay worked to the IDCSP’s advantage. By 1964, the development of the U.S.A.F.’s heavy-lift Titan IIIC offered the possibility of lofting up to eight satellites per launch. This has meant that the total number of launches required to establish the constellation, and thus the overall cost of the programme, has been greatly reduced. It seems that the Pentagon decided to negotiate “free rides” on early Titan IIIC development launches, although this earned some censure from Congress for risking the success of the programme with launches on an unproven vehicle just to keep costs down! Fortunately, it has been a risk that has largely paid off.

The Air Force decided to develop the Titan III family so that it would have a heavy launch capability independent of NASA’s Saturn rockets. The Titan III vehicles are derived from the Titan II I.C.B.M., that was also the basis of the Titan launch vehicle used for NASA’s Gemini programme. The core of the Titan IIIC is a modified two-stage Titan II, structurally strengthened to accommodate heavier payloads and additional stages. The launcher has two strap-on solid rocket boosters and an additional upper stage with engines that can be restarted, known as the Transtage.

The 25 ft long Transtage uses a pair of Aerojet AJ10-138 engines that are similar in design to the larger engine that Aerojet is developing for the Apollo Service Module. These engines enable the Transtage to put heavier payloads into much higher orbits than the Atlas Agena rocket originally selected for IDCSP. This means that it can place as many as eight IDCSP satellites at a time into sub-synchronous orbits (more on that below) of around 21,000 miles.

The complex requirements for the preparation and launch of a Titan III and its payloads has necessitated the construction of a totally new facility at Cape Kennedy, with three pads, designated Launch Complexes 40, 41 and 42 (this last not yet built). There is also a new Vertical Integration Building (VIB), which can support the simultaneous assembly of up to four Titan III core vehicles. It also contains the Titan III launch control centre.

Keep it Simple
The IDCSP satellites have been designed to avoid the development delays that come from being too technologically ambitious – the kind that sealed the fate of ADVENT. Every satellite in the constellation is an identical spin-stabilized, 26-sided polygon, 34in in diameter. The 100lb satellites are covered with solar cells and have been deliberately kept technologically very simple: they have no back-up batteries or on-orbit command systems. Without command systems, they are virtually “jam-proof” and cannot be moved off orbit by false commands sent by an enemy.

Each satellite has a single 3.5W X-band transponder with a 26 MHz bandwidth. It can handle 600 voice channels or 6000 teletype signals. While the designers have planned for these initial satellites to be operational for three years, they are equipped with an automatic “kill switch”, which is intended to deactivate them after six years in orbit, so that they will not produce any signals that would interfere with more advanced future replacement satellites.

As the small satellite’s transponders are low powered and use a low-gain antenna, the present ground stations are comparatively large, but there are plans for future, smaller mobile ground stations.

“Sprinkled Across the Sky”
One of the few local newspaper articles that I saw about the launch of the first batch of IDCSP satellites described them rather poetically as being “sprinkled across the sky” when they were first released into orbit from the Titan IIIC Transtage. Six hours after launch, the deployment truss on which the IDCSP satellites are mounted enables the satellites to be dispersed one-by-one into orbit, over about 3 minutes. As they are released, the satellites drift apart as they move into orbit.

Because they are not quite in geosynchronous orbit (orbiting at the same speed the Earth rotates, which would "fix" them in the sky), the satellites drift randomly at approximately 28° per day, over time forming a ring of satellites approximately evenly spaced above the Earth's equator. This sub-synchronous orbit has the advantage that the failure of one satellite would not leave a major gap in coverage; at least one other satellite of the constellation would always be visible to an Earth station if one failed. 12 satellites were considered the minimum necessary to provide full coverage, so the current constellation has plenty of redundancy even if several satellites fail. The daily movement of the satellites makes them difficult to track, which also helps to make them more secure against enemy interference.


What are they for? Ssshhh, it’s Secret!
The IDCSP constellation is designed to provide the U.S. military with swift, jam-resistant radio links to its forces in South Vietnam and elsewhere around the world in times of crisis. The satellites enable 24 hour-a-day contact between the Defence Department in Washington and forces in the field. While the IDCSP programme is publicly acknowledged, the satellites are reserved for secret and sensitive command-and-control communications. Routine administrative and logistical messages are relayed by INTELSAT satellites.

IDCSP ground terminals have been installed at American bases at Saigon and Nha Trang, and rumour has it that there have already been experiments with sending high-resolution photographs from Saigon to the Pentagon via satellite, enabling rapid battlefield analysis. In addition to the two ground stations in South Vietnam, there are six other IDCSP ground stations, including in the U.S. and Britain.

Building the IDCSP Satellite Network
The first batch of seven IDCSP satellites was launched from Florida on 16 June 1966, as the payload of the fourth Titan IIIC. In addition to the communication satellites, an eighth satellite, structurally based on the IDCSP satellites and designed to test an experimental gravity gradient stabilisation technique, was also flown. Communications tests were carried out between ground stations in New Jersey, California, England and Germany.

Unfortunately, the second set of eight IDCSP satellites was lost on 26 August 1966 due to the failure of the fifth Titan IIIC’s payload fairing. A replacement set of eight satellites was sent into orbit on the seventh Titan IIIC, on 18 January 1967, followed on 1 July by a further four IDCSP satellites. IDCSP 19 was another experimental satellite, also known as DATS (Despun Antenna Test Satellite), designed to test a more efficient electronically despun antenna platform.

The most recent launch, on 13 June, has come almost exactly two years after the first satellites in the network were put into orbit. Its eight satellites are the final ones to be added to the system, which is now considered to be “operational”, rather than “experimental”.

Britain Follows Suit
Britain has taken an interest in the operation and performance of the IDCSP satellites, as it intends to launch its own military communications satellite soon, to provide military communications across the British Commonwealth. Skynet has been in planning since 1962, with the U.K. deciding on an initial satellite in geostationary orbit over the Indian Ocean, to support force deployments east of Suez. Skynet is considered to be more advanced than IDCSP, as it will have a transponder with two channels, allowing communications between two types of ground station.

Model of a Skynet 1 satellite

Britain was invited to participate in IDCSP in 1965, and the Marconi company built a ground station at its facility in Christchurch, Hampshire, to conduct experiments with the first batch of IDCSP satellites when the U.S. was not using them. Nine ground stations have been planned for Skynet, which are also able to communicate with the IDCSP satellites. These stations will be able to send secret military communications to a large number of locations within the British Commonwealth.

The U.S. Philco Ford company, which developed the original IDCSP design, was contracted to build the first-generation Skynet 1 satellites (of which there will be two). The Marconi company is assisting with this work so that the U.K. will develop the expertise needed to build the Skynet 2 series satellites. Unlike the IDCSP constellation, Skynet satellites will have an on-board manoeuvring system so that they can be kept on station, or moved from one location or another.

With the United States and Britain developing defence communications satellite systems, it's virtually certain the USSR will be doing the same – if it does not have an operational network already (perhaps some of those mysterious Kosmos satellites whose purpose in orbit is unknown?) Since reliable communications are vital to any military operation, it's not hard to imagine that defence comsats like IDCSP and Skynet could become the first casualties in any future superpower conflict…








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Magazine, Science / Space Race

[June 18, 1968] I Just Read It for the Stories (February-June 1968 Playboy)

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by Erica Frank

Introduction

After looking over Playboy in January and finding Vonnegut's gem of a story, I decided to check out the next few issues. This time I skipped all the political commentary (which is mostly "money is good and women should wear fewer clothes") and focused on the stories and articles potentially of interest to science fiction fans.

March 1968 Playboy cover - a naked woman with a bunny painted on her back looks over her shoulder
Cover of March 1968's Playboy. I found this the least-boring cover of the set – the only one that looks like she's having fun.

I read everything that looked remotely like it might be a science fiction story, even though some of them were a stretch. I also looked at the science-related articles. There are quite a few of them, since this covers a five-month period.

A Day in the Life of…, by Ralph Schoenstein (February)
The full title of this story is "A Day in the Life of President George Romney—Or Robert Kennedy, Richard Nixon, Ronald Reagan, Martin Luther King, Charles Percy, Hubert Humphrey, Nelson Rockefeller, Lurleen and George Wallace." It's a satire inspired by Jim Bishop's A Day in the Life of President Johnson, speculating about the biographies of other potential presidents. I had hoped this involved some kind of parallel universe setting, or time travel… but no. This is just mild political commentary, a few paragraphs of satirical character study on each.

Romney awakens at 5 a.m. and scowls at his wife for addressing him by his first name. Kennedy leaps from his bed and cartwheels into the bathroom. Nixon polls his public to find out if he should get out of bed in the morning. Reagan is refraining from sex for the duration of his presidency to avoid the risk of marks. King never smiles and never argues. Humphrey worships LBJ and calls him "Big Daddy."

As satire: 3 stars. As science fiction: 1 star–there's some vague hint of multiple universes, but that's all.

Hat Trick, by Robert Coover (February)
Certainly interesting. A magician performs a hat trick – pulling bunnies, doves, another hat, and eventually, a whole assistant out of his hat. And then the story turns dark. This had some surprising twists and a disturbing ending.

4 stars; this one will stick with me.

The Chronicle of the 656th, by George Byram (March)
The set-up: a former student brings his professor a locked box, found buried under a house he'd purchased. The box contains Civil-War-era documents and objects – and a notebook dated 1944. After establishing that this was not a hoax, he'd read through the notebook: an entire army combat team had vanished from their WWII training area and found themselves in 1864. They help win a major Civil War battle, although several of the team members are conflicted – their families and ancestors are from the South.

The writing is good, but the story is not. Everyone dies, so there's no time paradox to address. It reads like normal fiction, not like a series of diary entries. I guessed the big secret as soon as they established what happened. (Secret atomic bomb testing sent them back in time! How shocking!) This must be what the mundanes think science fiction is supposed to be.

2 stars. Unless you enjoy war stories, in which case, it may be 3.

The Origin of Everything, by Italo Calvino (March)
This "story" is two vignettes that take place at the beginning of the universe – one before the Big Bang (or, mostly before), and one a bit after. They are both whimsical explorations of the idea of "people" in places where people obviously cannot exist.


The art by George Suyeoka nicely captures the feel of the story.

There's a surreal conjunction the everyday and the cosmic: Mrs. Ph(i)Nko taking Mr. De XuaeauX to bed, but since they are all in a single point before the expansion of the universe,

…"it isn't a question of going to bed, but of being there, because anybody in the point is also in the bed. Consequently, it was inevitable that she should be in bed also with each of us.

After the creation of the universe, all of the residents of the point hope to find Mrs. Ph(i)Nko again, but alas, she cannot be found; only the memory of her love for them all survives.

In the second vignette, astral children play marbles with hydrogen atoms; one child has stolen all the new atoms, and one of his companions then tricks him with fake atoms made of junk.

4 stars; this was delightful.

The Bizarre Beauties of "Barbarella" (March)
This is a pictorial review of the movie that's coming out later this year, based on the French comic, "The erotic space adventures of Barbarella." I'm not familiar with the comic, but I gather it has

  • Beautiful women
  • Wearing very few clothes
  • Having sex
  • In space


The Black Queen enjoys a dream interlude with the angel Pygar, whom she's forced to obey her will.

Fashion of the future on the planet Lythion

Barbarella rescues Pygar, and then Pygar rescues Barbarella.

I'm not rating this, but I am looking forward to the movie when it comes out.

Bucking the scientific Establishment, by Theodore J. Gordon (April)
This is a nonfiction article about innovative scientists who were initially faced with derision and insults, and were later proved to be correct. …Or rather: this is an article about innovative historical scientists, and a handful of current scientists whose theories are still considered more in the category of "crackpot" than "fact," which the author would like you to believe are very plausible, as shown by the fact that several other scientists used to be considered crackpots but are now lauded as groundbreakers in their fields.

Author seems to have skipped over the thousands of so-called scientists who were widely believed to be crackpots and later were still believed to be crackpots.

2 stars. Reasonably entertaining writing; good facts; bad science.

Papa's Planet, by William F. Nolan (April)
This is short and I wish it were forgettable. Fortunately, it's incoherent enough that most of the details will fade with time. Philip, our protagonist, is Cecile's fourth husband; her father recently died and left him the deed to a planet. The story is obviously not meant to be taken seriously ("Five million miles out from Mars, we turned sharp left and there it was: Papa's Planet"), and while it's obviously science fiction–the planet is inhabited by nothing but Hemmingway clones–there's not really any actual story here. (Is this what the mundanes think science fiction is?)

2 stars. It's not anything like good but it's not overtly bad enough for me to rank it at 1 star.

The Annex, by John D. MacDonald (May)
I had hopes for this one. It started out interesting: a nurse tending an unconscious patient, discovering he's dislodged his IV needle. Then it shifts perspective entirely: Mr. Dave Davis visits a huge, strange building, in the process of being torn down while its residents refuse to leave. There are hints that he's on some kind of assignment from an agency; he tries not to reveal exactly why he's visiting or how he got access. His guide, Mrs. Dorn, refuses to let him find his own way, insisting he'd just get lost. (It is clear that yes, he would quickly get lost.) When they reach his destination–

The story loses focus. It gets a bit surreal; while I generally enjoy surreal–see my notes about the Calvino story above–this lacks the whimsy or allure that would allow it to be more than somewhat nonsensical. Then the story shifts back to the nursing ward, where Silvia Dorn is a nurse, her beloved Dave is being kept alive by machines, and the reader is obviously meant to draw meaning from these details in a way that eluded me.

3 stars, I suppose–I can tell there's a decent story here even if it seems to want a set of assumptions I don't share.

Henne Fire, by Isaac Bashevis Singer (May)
This is told folktale-style, a story of Jewish fantasy (of a sort) rather than classic science fiction. Henne Fire is a terrible woman–she has been so awful, all her life, that she basically became a demon. Or perhaps she was born as one. She was nasty to everybody. Eventually, she became prone to random attacks of hellfire–her clothing would catch fire, or little flames would start around her. She could not even move into the poorhouse; nobody wanted a boarder who would catch houses on fire. She pleaded with the rabbi to help her, and eventually, the town made her a small brick house–basically a shack made of stone, with a tin roof.

Illustration by Bernard McDonald

The neighbors might've just shunned her after that, but one of her daughters married a rich American and started sending her money. Suddenly everyone wanted to befriend her. (This did not make her a nicer person.) One day people noticed that Henne hadn't been around for a few days, and they found her remains at home–a burnt skeleton, sitting in a chair with no mark of fire on it.

3 stars; entertaining enough.

The Dead Astronaut, by J. G. Ballard (May)
After the space age is decades past–shut down after a bloody history of orbital accidents–a married couple awaits the crash landing of their friend who died 20 years ago, so they can gather his remains.

Charle Schorre's illustration is eye-catching and does not actually capture the tone of this semi-post-apocalyptic story.

I enjoyed this story, although it is not a happy tale and it does not end well for anyone. I especially enjoyed: Mrs. Groves had been (was still?) in love with the astronaut, and her husband does not seem to have been jealous–mostly amused, and a bit concerned for her. I did not enjoy: The revelation of the ominous secret (a bit too predictable), and the final moments where the husband says, "I never asked you–" and then looks at her, and realizes he has his answer.

What that answer was, what the question was, I do not know. This was obviously written for men of a certain class, of a certain culture, who would understand the unspoken words. I can recognize the poignancy of the ending but I don't know what actually happened.

3 stars. If I'd been part of the intended audience, it probably would be 4.

The Snooping Machine, by Alan Westin (May)
Another nonfiction piece, positing a cashless, computer-data-driven society by 1975. It mentions that computer tape is so efficient a storage medium that one could hold 2000 pages of data for each of America's two hundred million citizens in a single room, on as few as a hundred reels of tape.

It discusses some history of government data-gathering, which includes both "big brother" hysteria and a pressing need for accurate data on which to base decisions. (Which regions need better school funding? Which areas might need new roads?) Government officials have admitted it may be impossible to separate personal identity details from the data they need, and that sorting out the conflicting interests in privacy and data is an ongoing problem.

3 stars. A nice overview of data technology and both the problems and possibilities it brings, but a bit pedantic in approach.

The Man from Not-Yet, by John Sladek (June)
Epistolary fiction, told through letters. Two friends in 1772 discuss an incident some ten years past, in which they had a visitor who claimed to be from the future. He was questioned by Samuel Johnson, who asked disparaging questions–"You will want to tell me no doubt of carriages that operate without benefit of horses. Of engines that carry men through the air like birds. Of ships without sails."

The visitor is astounded that he has guessed the future so correctly, but Johnson just scoffs, until the man offers to bring him to the future. They visit his time machine; the two enter the device; after a few moments of silence, it glows and explodes, leaving Dr. Johnson in the wreckage but the traveler gone.

The remaining few letters let the readers know what happened, while the men themselves remain unaware.

3 stars. I have little interest in this kind of historical fiction, and there is almost no point to the story: too much exposition with a "gotcha" twist at the end.

Ghost, by Hoke Norris (June)
The protagonist of this story is a somewhat conservative, ambitious man who has a "ghost" that speaks to him constantly, urging wild and rebellious acts. The ghost was the previous inhabitant of his body, and he cannot get rid of it even though he is now in control. He is also dating the boss's wife's sister (instead of the girl he loves). He wants the money and status that comes with the high-class connections but he also wants the comfort and joy he finds with Marie; he is caught between these two issues (with the ghost constantly berating him for his ambition) until Marie turns up pregnant.

They have a fight, he goes for a walk, and everything changes.

4 stars–this one will (heh) haunt me.

Conclusion

Playboy is about on par with most science fiction magazines for quality, and better than some… if you can accept that it has only one to three pieces per issue that are relevant to science fiction fans. Although the stories are okay, with some much better than that, many of the best-written stories have dark themes or unhappy endings or both. It seems the average Playboy reader is not expected to be interested in stories of otherworldly exploration or how technology might solve our problems, but how people with psychic powers or spaceships are just as likely to be miserable as the average person today. It's heavy on pedantic verbosity and all rather depressing.

If you also like the libertarian politics, there is more entertainment per issue, and of course, if your interests include pictures of young women with their shirts off, it has quite a bit to offer.




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Science / Space Race

[MAY 26, 1968] EUROPA AD ASTRA (EUROPEAN SPACE UPDATE)

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by Kaye Dee

The recent launch of the ESRO 2B scientific satellite on 17 May (more on that below) reminds me that it has been a while since I wrote anything about the European launcher development programme being carried out in Australia. There have also been major developments in Europe’s space plans over the past few months, which look like they will significantly change the future of the European space programme.

For readers in the United States and other parts of the world, who may not be familiar with the European space programme, let me take a few moments to introduce the major players and provide a bit of background before talking about recent developments.

Cousins Rather Than Siblings: ELDO, ESRO and CETS
The two most important space bodies in Europe are the European Space Research Organisation (ESRO) and the European Launcher Development Organisation (ELDO). ESRO’s focus is on developing scientific satellites for space research. ELDO looks to develop an independent satellite launch capability for Europe through the Europa rocket, conducting its test flights from the Woomera Rocket Range in Australia.

The French acronym CERS stands for Conseil Européen de Recherche Spatiale

These roles would appear to be complementary, and I have occasionally referred to ELDO and ESRO as “sister” institutions in previous articles, since they have grown up in parallel and have several member states in common. However, I’ve come to think that they are perhaps best considered as “cousins”, as they operate and forward plan quite separately from each other, resulting in a lack of co-ordination across Europe's space activities. While ELDO was established with an assumption that ESRO would be one of the customers for its launch services, ESRO has not waited for a European launcher to become available from ELDO: ESRO 2B has been launched under NASA’s auspices on a Scout vehicle from Vandenberg Air Force Base and for the foreseeable future all planned ESRO satellite launches will be on US rockets.

The French acronym CECLES stands for Conseil européen pour la construction de lanceurs d'engins spatiaux

Mention also needs to be made of the European Conference on Telecommunications by Satellites (CETS), the third space organisation in Europe, which is playing a role in pushing for some of the proposed changes in Europe’s space plans. Unlike ESRO and ELDO, CETS is not active in developing space technologies and vehicles, but provides a forum for European Post, Telegraph and Telecommunications agencies (PTTs) to consider the role of communication satellites and discuss the European role in the INTELSAT global telecommunications satellite system.

ESRO and ELDO: Parallel Lives
Stemming from initiatives taken in 1959 and 1960 by a small group of scientists, led by Italian Prof. Edoardo Amaldi and French physicist Prof. Pierre Victor Auger, ESRO was set up in the early 1960s. Like ELDO, it formally came into existence in 1964. ESRO’s member countries are Belgium, Denmark, West Germany, France, Italy, the Netherlands, Sweden, Spain, Switzerland, and Britain, and the organisation’s focus has been on strictly civil scientific research. Four ESRO members (Britain, France, Italy and West Germany) also have their own national space programmes.

ESRO has already developed a number of technical facilities: the European Space Research and Technology Centre (ESTEC) in the Netherlands, is the newest, opened on 3 April. ESRO has also begun to establish its own space tracking network, ESTRACK, and has its own sounding rocket launch facility, ESRANGE (established in 1964), near Kiruna, Sweden.

The opening of ESTEC on 3 April by HRH Princess Beatrix and her husband Prince Claus included the royal couple being presented with a model of the ESRO 2B satellite

ELDO, on the other hand, was very much a British initiative in 1960-61, seeking partners in Europe for the development of an independent satellite launcher that would use as its first stage the UK’s then-recently cancelled Blue Streak missile. ELDO’s member states are Britain, France, West Germany, Italy, Belgium and the Netherlands. Australia, despite being a non-European country, is also an ELDO member because of its role providing the test launch facilities at Woomera.

The first Blue Streak launch from Woomera in 1964, designated as ELDO F-1, the inaugural test flight of the Europa rocket's first stage

Both organisations operate with a policy of “juste retour” – allocating work to industry in member countries in proportion to their share of financial contribution to the organisation.

So you can see that, unlike the US civilian space programme, under the control of NASA, and the Soviet programme, under central control from the Politburo, there are many fingers in the European space pie, with many complementary and yet competing interests and national agendas.

Not Going Up from Down Under
When I last reported on the ELDO programme, it was to cover the loss of the ELDO F-6 launch in August last year. At the time, I mentioned that a reflight – designated as F-6/2 – was already in planning. Scheduled for December 5, 1967, the first attempt to launch F-6/2 was aborted just 12 seconds before lift-off due to a power failure.



Although successfully launched at 6 a.m. the following morning, the second stage failed to ignite after separation from the first stage. The vehicle then crashed down into the upper reaches of the Simpson Desert, repeating the failure of Europa F-6/1. This was the second failure of an active French Coralie second stage, and an investigation is still underway to determine the cause.

Despite this failure, the next Europa launch – designated F-7 – is still planned for October or November this year as the first test flight with three active stages. Let’s hope that the issues with the second stage have been resolved by then!

Has Britain Lost Its Way in Space?
Since coming to power in the October 1964, the Wilson Labour Government has shown itself to be considerably less enthusiastic about European space activities than its Conservative predecessor. This would appear to be in large part due to the struggling UK economy, but also a response to the lack of success of Britain’s attempts to join the European Economic Community in 1963 and 67, for which UK participation in European space was supposed to be a sweetener.

In 1965, when the cost of completing the original ELDO programme had already climbed to twice the early estimates, France began to call for a revised – and more expensive – programme to develop the Europa vehicle into a launcher capable of placing satellites into geostationary orbit. Calling the Europa I launcher “obsolete”, as it can only place satellites into polar orbit, France has proposed a more sophisticated and powerful Europa II vehicle that would enable Europe to launch communications and other applications satellites without reliance on the United States (which has already given indications that it will take measures to protect its monopoly on the use of geostationary satellites).

Applications satellites, especially for international communications (as demonstrated by INTELSAT), are almost certainly the way of the future in space developments outside human spaceflight, and West Germany, Belgium and the Netherlands have agreed with the French view. This resulted in a July 1966 proposal to complete ELDO’s Europa I programme and add a Europa II development programme.

The British Government, however, began to express severe doubts about the “technological use and the economic viability” of the ELDO programme and opposed the French-led changes. In 1966, it signalled that Britain would not participate in any further financing of ELDO programmes after present projects were completed. Britain also reduced its financial contributions to ELDO from 38.79% (the largest contribution to ELDO’s budget) to 27%, with the difference being made up by the other four paying members (Australia being a non-paying member, on the basis of providing the Woomera facilities).

The reduction in the British financial clout within ELDO, and the desire for an equatorial launch facility, has been a factor in ELDO planning to move away from Woomera to France’s national launch facility in Kourou, French Guiana, at the completion of the ELDO I programme, anticipated in 1970. This has greatly disappointed my friends at the WRE, who spent considerable effort in preparing plans for a launch facility near Darwin, in the Northern Territory, to support an equatorial launch capability in Australia for the Europa II programme.

The first launch from France's Kourou facility, the future home of the ELDO programme, took place on 9 April this year, with the firing of a Veronique sounding rocket

British Space Industry Weighs In!
In November last year, a report from the National Industrial Space Committee, which represents the space interests of British industry, recommended that the British Government should not reduce, but expand its spending on space research and development, in order to stop the brain drain from the UK and obtain a share in what is already being seen as the lucrative space technology business. It recommended that spending on space-related R&D should be increased by around a 25% increase from the present $A60 million to between $A75 million and $A87.5 million said the committee. Comments at the time from Mr Kenneth Gatland, vice president of the British Interplanetary Society, indicated that a major row was looming between industry and Government over Britain's failure to lead Europe into the commercial field of communication satellites. Although the Post Office, which controls British telecommunications, has expressed “severe doubts” about the commercial benefits of space-communication, this seems a bit strange when the Post Office is also the British signatory to INTELSAT, and the UK is the consortium’s second largest shareholder. “Government advisers”, Mr. Gatland said, “were being accused of leaving Britain high and dry through inept policies, allowing France and West Germany to benefit at Britain's expense.” Instead of the “national scandal” of Britain having spent an estimated $A124,707,500 on ELDO without any tangible end project in view, Mr. Gatland has suggested that Britain should give ELDO a target which would bring a return for the large capital investment.

A European Symphonie?
Whatever Britain’s misgivings regarding satellite communications, France and Germany are eager to move into the field of communications satellites to break INTELSAT’s monopoly on international satellite telecommunications. They have embarked on their own joint communications satellite project, known as Symphonie. As this project has taken options on two Europa II launches for its two satellites, it is, at present, ELDO's only customers! Mr Gatland has urged Britain to join France and Germany in the Symphonie project, which will promise a satellite in three to five years.

An early design for the Symphonie communications satellite, which is intended to be three-axis stabilised

Italy has decided to go it alone on the development of a telecommunications satellite known as Project Sirio. The design will apparently be based on the experimental telecommunications satellite that Italy was originally going to develop for ELDO, before that aspect of the programme was cut to reduce overall costs.

ESRO is also reported to be interested in moving beyond scientific satellites into the applications satellite area, in conjunction with CETS, which has expressed interest in the development of a satellite for television distribution.

Whither or Wither, Europe?
With all this history in mind, Europe’s space plans for the future have undergone considerable change in the past few months. According to a report released in March, Europe's space club has mapped out an ambitious programme for the next 10 years that would include telecommunications satellites for television, broadcasting and telephone calls, meteorological, air traffic control and Earth resources satellites, and large numbers of astronomical and other scientific satellites. This programme, which involves a 10 per cent annual increase of expenditure on European space projects, is intended to be discussed when Science Ministers from the 17 member states of ELDO, ESRO and CETS, meet in Bonn, West Germany, in June.

However, the ambitious proposals released in March evolving as originally anticipated is now unlikely, given the most recent events. On 18 April, Britain's Labour Government announced cuts in spending on space research and cast further doubts on the future of ELDO. Although the Government indicated that it would maintain its contribution to the current ELDO programme at the existing level, it could “see no economic justification for undertaking further financial commitments to ELDO after the present programme,” which is due to conclude in 1970.

This (not totally unexpected news) was followed by an announcement from ESRO on 26 April that it was cancelling its plans for its two largest satellites scientific satellites – a major blow for European space co-operation. The two massive TD 1 and TD 2 satellites (the TD stands for Thor Delta, the intended launch vehicle), each weighing 990 lbs, were to have been built under a 100 million franc (about Aus$17,800,000) contract by an international consortium including Hawker Siddeley Dynamics of Britain, the French firm Matra, the West German group ERNO, and Saab of Sweden.

TD1, scheduled for launch in 1970, was designed to study the relationship between earth and sun. TD2, planned for launch the following year, was focused on research into solar ultra-violet radiation and electromagnetic phenomena in the upper atmosphere. The reason for the satellites’ cancellation seems to be connected with disagreements within ESRO in regard to the juste retour allocation of work for the project.

ESRO’s First satellite in Orbit!
Despite the uncertainties about its future space plans, Europe is currently celebrating the launch of the first ESRO satellite to make it to orbit! ESRO-2B was launched 17 May from Vandenberg Air Force Base in California on a Scout B rocket.

This flight occurred almost exactly one year after the loss of its predecessor ESRO 2A on 29 May, 1967. Also launched from Vandenberg on a Scout B, ESRO 2A was lost due to a malfunction of the rocket’s fourth stage, which prevented the satellite from reaching orbit. These first European satellites were launched on Scout vehicles due to an offer from NASA to launch the ESRO's first two satellites free of charge as a ‘christening gift’ for the organisation (and no doubt to woo ESRO towards continuing with US launchers even when ELDO's Europa rockets become operational!)

ESRO 2B, also known as Iris (International Radiation Investigation Satellite), Iris 2 and ESRO 2, is an astrophysical research satellite developed to study solar and cosmic radiation and their interaction with the Earth and its magnetosphere. This will provide continuity to the solar radiation observations of earlier satellites and continue similar particle measurements carried out by the UK’s Ariel 1 satellite. It is the first mission controlled by teams at the European Space Operations Centre (ESOC) in Darmstadt, Germany.

ESRO 2B being prepared for launch

Placed into a highly elliptical near-polar orbit, with an orbital period of 98.9 minutes, ESRO-2B is about 33.5 inches in length, with a diameter just on 30 inches. It weighs 196 lb and is spin-stabilised, with a spin rate of approximately 40 rpm. The satellite is powered by 3456 solar cells on the outer body panels, supplemented by a nickel/cadmium battery. The satellite carries the same seven instruments as its lost predecessor: to detect high-energy cosmic rays, determine the total flux of solar X-rays, measure trapped radiation, investigate Van Allen belt protons and cosmic ray protons. And if you’re wondering why ESRO 2B is the first European satellite and what happened to ESRO 1, the simple answer is that ESRO 1 has yet to be launched! Difficulties in the development of the payload for the polar ionospheric satellite ESRO 1, designed to study how the auroral zones responded to geomagnetic and solar activity, meant that it was eventually agreed to launch ESRO-2 ahead of it. ESRO 1 is due for launch around October this year, so we here at Galactic Journey will cover its story soon. ESRO 2B being tracked at the ESOC mission control centre










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Science / Space Race

[April 8, 1968] Ups, Downs and Tragedy: An Eventful Month in Space (Gagarin's crash, Zond-4, OGO-5, Apollo-6)

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by Kaye Dee

Despite the continued hiatus in human spaceflight on both sides of the Iron Curtin, March and early April have been a busy time in space exploration. But, sadly, I have to commence this review with the tragic news that Colonel Yuri Gagarin, the first person in space, was killed in a plane crash during a training flight on 27 March. Very little is currently known about the circumstances surrounding Gagarin’s death, which has occurred just one month shy of the first anniversary of the loss of Cosmonaut Vladimir Komarov in the Soyuz-1 accident.

Loss of a Space Hero
There have long been rumours that the Soviet leadership refused to allow Gagarin to fly high performance jets or make another spaceflight due to his invaluable propaganda status as Cosmonaut No. 1. However, it seems that since Gagarin completed an engineering degree in February, he had finally been allowed to resume flight status and was undertaking training flights to regain his lapsed jet pilot qualifications.

According to an official government commission investigating the crash, Col. Gagarin was flying a two seat MiG-15 trainer with Colonel Vladimir Seryogin, 46, described as an experienced test pilot and instructor on the training flight. Taking off at 10 a.m., Gagarin and Seryogin apparently flew east 70 miles from Moscow. After completing the training flight, around 10.30, Gagarin radioed that he was returning to base. The plane was then at 13,000 feet. A minute later ground control could not establish contact.

A MiG-15UTI, the same type as the aircraft Gagarin was flying at the time of the crash

An air search began, and a helicopter found the wreckage in a forest. The plane had dived into the ground at an angle of 65 to 70 degrees and was destroyed, killing both men. No information as to the cause of the crash has so far been forthcoming, but a story has been circulated that Gagarin heroically sacrificed himself, refusing to bail out of his stricken aircraft to guide it away from crashing in a populated area. How much truth there is to this, or whether it is pure propaganda, cannot be determined at this time.

Cosmonaut No. 1 is “flying through space forever”
Following an autopsy, the bodies of Gagarin and Seryogin were cremated the day after the crash and the ashes returned to Moscow, where the urns lay in state for 19 hours in the Red Banner Hall of the Soviet Army. Thousands are reported to have filed past to pay their respects to the world’s first space traveller. Thousands more lined the streets as the flower-covered urns, borne on a caisson drawn by an armoured troop carrier, moved slowly to Red Square along a 2½-mile route. The funeral procession included the Gagarin and Seryogin families and the highest leaders of the Soviet state and Communist Party.

The funeral procession for Gagarin and Seryogin making its way towards Red Square

Gagarin and Seryogin were both interred in the Kremlin Wall, behind Lenin's Tomb in Red Square. In what is said to be a rare honour, car horns, factory whistles and church bells sounded in unison as the urn bearing Gagarin's ashes was inserted into a niche in the red brick wall. Then the nation fell still for a minute of silence, followed by a final salvo of cannon fire. A day of national mourning was also declared, the first time this has ever been done in the USSR for someone not a national leader. President Johnson, UN Secretary General U Thant and other world leaders sent messages of condolence. John Glenn sent a personal letter of sympathy to Col. Gagarin’s wife Valentina.

Seryogin and Gagarin buried side by side in the Kremlin Wall. Their various honours and awards are displayed before their portraits

Gagarin was just 34 years old when he died, leaving two young daughters, aged nine and seven. He was based at the cosmonaut training centre near Moscow, involved in training other cosmonauts when not engaged in official duties as a public figure. Little is known about Col. Seryogin, but he has been described as a Hero of Soviet Union and the commander of an air unit. It is unknown if he is also a member of the Soviet cosmonaut corps or has any other role in the Russian space programme.

Gagarin’s words upon landing after his space flight were “I could have gone on flying through space forever”. Though he never returned to space in this life, his spirit surely resides in the cosmos now.

Making up Lost Ground?
The somewhat mysterious Zond-4 unmanned spacecraft was launched on 2 March. A TASS news agency announcement of the launch described Zond-4 as an “automatic station”, “designed to study the outlying regions of near-earth space.”

Thanks to my friends at the Weapons Research Establishment, here is a photo of a Proton rocket, rumoured to be the type used to launch Zond-4.

TASS reported that Zond-4 was put into an initial 170-mile parking orbit, before being sent on a “planned flight” further into space, apparently reaching the environs of the Moon. According to my contacts at the WRE, Zond 4’s flightpath reached an apogee of 240,000 miles, “comparable to lunar altitude”.

No further information was released by TASS about the mission, which has occurred several years after previous launches in the Zond series: Zond-1 was launched in April 1964, Zond-2 in November that year, and Zond-3 in July 1965. “Zond” is the Russian word for “probe” and these earlier spacecraft were apparently planetary or lunar missions. Could Zond-4 actually have been an attempt by the Soviet Union to make up lost ground with a test of the new Soyuz spacecraft, presumably redesigned or modified following the failed Soyuz-1 mission last year?

Does this cutaway illustration represent mysterious Zond-4? My WRE friends think it might!

It would hardly be the first time that the Soviet Union has concealed real purpose of a space mission behind the name of a different spacecraft series. (paging Mr. Kosmos/Cosmos!). As the Soyuz vehicle is believed to be the USSR’s answer to Apollo, a test of an improved spacecraft out to lunar distance would certainly make sense at this time, with the Apollo 6 mission (see below) testing out the Apollo Command and Service Modules just a few days ago.

Whatever its mission, Zond-4 returned to Earth on 9 March, but there was no official communique on the conclusion of the flight. This silence suggests that the re-entry failed in some way and that the spacecraft was either destroyed on re-entry or crashed on landing. If Zond-4 was a test of the Soyuz vehicle, could its loss have been due to a repeat of the parachute failure that doomed Soyuz-1 last year? If this was the case, it does not bode well for the USSR getting its lunar programme back on track in time to challenge the United States in the race for the Moon.

Go, OGO-5!
Just two days after the launch of Zond-4, the United States launched the latest satellite in its Orbiting Geophysical Observatory (OGO) series of scientific satellites. OGO-5 soared aloft on 4 March, establishing itself in a highly elliptical orbit with a 170 mile perigee and a 92,105 mile apogee. The orbital inclination was 31.1 degrees, with the satellite taking 3796 minutes to complete one orbit. The 1,347 lb satellite carries more experiments than any other automated spacecraft to date.

OGO-5 First day Cover and informational insert, courtesy of my Uncle Ernie, the philatelic collector

OGO-5 is primarily devoted to observation of the Earth’s upper atmosphere and its interaction with conditions in the space environment. Like earlier OGO satellites, it carries instruments for studying solar flares (which can also detect cosmic X-ray bursts) and a gamma-ray detector. This will enable it to examine the hazards and mysteries of Earth's space environment at a time when radiation-producing flares on the Sun are intensifying. It will also chart magnetic and electric forces in space, measure gases in Earth's upper atmosphere, investigate the Aurora Borealis over the North Pole and listen for the puzzling radio noises that have been detected from the planet Jupiter.  Each of OGO-5’s predecessors is still operational at this time, so let’s hope the latest Orbiting Geophysical Observatory also has a long life ahead of it.

Apollo 6: NASA Keeps Moving Forward
If Zond-4 has been an un-announced trial of the USSR’s Soyuz lunar spacecraft, Apollo-6 has been NASA’s very public test flight of the Saturn-5 rocket and some of the modifications to the Apollo Command Module.

Launched on 4 April, Apollo-6 marked the second test flight of the massive Saturn-5 launch vehicle, crucial for reaching Moon. The primary objective of the mission was to test the performance of the Saturn-5 and the Apollo spacecraft, the first time that the Command and Service Modules (CSM) would be fully tested in space. In particular, the mission was intended to demonstrate that the Saturn-5’s S-IVB third stage could send the entire Apollo spacecraft (CSM and Lunar Module) out to lunar distances. Although things didn’t go quite to plan, Apollo-6 did accomplish its basic objectives.

An All-Up Test Flight
The Apollo 6 launch vehicle was the second flight-capable Saturn-5, AS-502, its simulated payload equal to about 80% of a full Apollo lunar spacecraft. The CSM it carried was a Block I (Earth-orbit mission) type, with some Block II (lunar mission) modifications. According to NASA “more than 140 tests since last October showed modifications of the Apollo spacecraft since the 1967 disaster had drastically reduced the hazard to life”.

Possibly the most important modification was a new crew hatch, intended to be tested under lunar return conditions. This new hatch incorporated the heat shield and crew compartment hatches of the original Apollo design into a single hatch, called the "unified" design. This has been in response to the Apollo-1 investigation board finding that the dual hatches were too difficult to open in case of emergency and had contributed to the deaths of the crew.

Apollo-6's redesigned unified hatch, photographed during a post-flight inspection of the Commend Module

Like the earlier Apollo-5 test flight, Apollo-6 carried a simulated Lunar Module (LM) which lacked the descent-stage landing gear. It also had no flight systems, and its fuel and oxidiser tanks were liquid-ballasted. While the LM remained inside the Spacecraft-Lunar Module Adapter throughout the flight, its ascent stage was instrumented to determine the craft’s structural integrity and the vibration and acoustic stresses to which it was subjected.

Apollo-6's "legless Lunar Module", formally called the Lunar Test Article LTA-2R

A few weeks prior to launch, NASA announced that, to further reduce fire hazards that contributed to the deaths of Apollo-1 astronauts, it intended to change to a mixture of 60% oxygen and 40% cent nitrogen in the Command Module, while the spacecraft and its crew are on the ground and during launch. Once their spacecraft left the launch pad, the astronauts would switch to pure oxygen. Since the gas mixture will be used in the spacecraft only during ground operations, NASA has not planned any change in the existing environmental control system, so the decision did not affect the Apollo 6 mission.

Apollo 6: What Was Planned
The original Apollo 6 mission plan intended to send the CSM and simulated lunar module into a trans-lunar trajectory. (That trajectory, although passing beyond lunar orbit distance, would not encounter the Moon, which was in another part of its orbit at the time.) The Saturn-5’s S-IVB third stage would be fired for trans-lunar injection, with the CSM separating from the S-IVB soon after. The Service Module engine would then fire to slow the CSM, reducing its apogee to 11,989 nmi.

NASA illustration showing the CSM and LM inside the Spacecraft-Lunar Module Adapter, as they would be at trans-lunar injection

The CSM would then return to Earth as if it had experienced “direct-return” abort during a Moon mission. As it returned, the SM engine would fire again, accelerating the CSM to simulate the conditions that an Apollo spacecraft would encounter on its return from the Moon: a re-entry angle of −6.5 degrees and velocity of 36,500 ft/s. The entire test flight was planned with a duration of about 10 hours.

Not Quite Going to Plan
After the launch was delayed for some days due to problems with guidance system equipment and fuelling, Apollo 6 made a smooth lift-off from Kennedy Space Centre. However, during the last ten seconds of first stage firing, the vehicle severely experienced a type of longitudinal oscillation known as “pogo”. Pogo occurs when a partial vacuum in a rocket’s fuel and oxidiser feed lines reaches the engine firing chamber, causing the engine to “skip”. The pogo phenomenon is well-known, since rockets have experienced it since the early days of spaceflight, and it occurred in launchers such as Thor and Titan II (used for the Gemini program).

While the Apollo-4 Saturn-5 also experienced a mild form of pogo, Apollo-6 was subjected to extreme pogo vibrations. It appears that these oscillations, travelling along the length of the huge Moon rocket, caused multiple problems with the vehicle. Two engines in the second stage shut down early, although the vehicle's onboard guidance system was able to compensate by burning the remaining three engines for 58 seconds longer than planned. The S-IVB engine also experienced a slight performance loss and had to burn for 29 seconds longer than usual. Intense vibrations were felt in the Command Module that could have caused injuries had a crew been onboard. There was also some superficial structural damage to the Spacecraft Lunar Module Adaptor (SLA). A chase plane image of the Apollo-6 launch, taken at approximately the time of the pogo oscillations. It shows an area of discoloration on the SLA indicative of superficial damage and what appears to be falling pieces of debris, perhaps a panel or two shaken lose by the pogo vibrations

The underperformance of the apparently pogo-damaged engines resulted in the third stage being inserted into an elliptical parking orbit, rather than the planned 100 nmi circular orbit. Although Mission Control decided that this did not prevent the mission from continuing, when the vehicle was ready for trans-lunar injection, the apparently damaged S-IVB engine failed to restart.

Repeating Apollo-4
Without the ability to continue with the original flight plan, Mission Control decided to complete some of the mission objectives by adopting a flight plan similar to that of Apollo-4. The SM's Service Propulsion System (SPS) was used to raise the spacecraft into an orbit with a 11,989 nmi apogee, from which it would re-enter. However, the SPS engine did not have enough fuel for a second burn to accelerate the atmospheric re-entry and the spacecraft was only able to enter the atmosphere with a velocity of 33,000 ft/s, instead of the planned 36,500 ft/s that would simulate a lunar return.

With the SM was jettisoned just before atmospheric re-entry, the CM splashed down 43 nmi from the planned landing site north of Hawaii, ten hours after launch. It was recovered by the USS Okinawa.

A Rocket's Eye View
Unlike earlier unmanned missions, the Apollo-6 Saturn-5 was fitted with several cameras intended to be ejected and later recovered. Three of the four cameras on the first stage failed to eject and were lost and only one of the two cameras on the second stage was recovered. Fortunately, this camera provided spectacular views of the separation of the first and second stages.

Two spectacular views of the interstage between the first and second stages falling away, taken from Apollo-6's second stage camera. How amazing that we can now see events happening during a launch that cannot be observed from the ground!

The CM also carried two cameras: a motion picture camera, intended to be activated during launch and re-entry and a 70mm still camera. Unfortunately, as the technical issues meant that the mission took about ten minutes longer than planned, the re-entry events were not filmed. However, the still camera, pointed at the Earth through the hatch window provided impressive photos of parts of the United States, the Atlantic Ocean, Africa, and the western Pacific Ocean. Advanced film and filters, improved colour balance and higher resolution have provided images that are a significant improvement on the photographs taken on previous American crewed missions and demonstrated that future imagery from space will be useful for cartographic, topographic, and geographic studies.

A view of the Dallas-Fort Worth area in Texas, taken from the Command Module's 70mm still camera. Special thanks to the Australian NASA representative for providing me with rush copies of these incredible Apollo-6 images for this article

What’s Next for Apollo?
NASA announced in mid-March that its first Earth-orbiting Apollo mission will be launched on a Saturn 1 vehicle and spend as long as ten days in orbit. The flight, which could come as early as mid-August, will be crewed by astronauts Walter Schirra, Donn Eisele and Walter Cunningham. If that mission goes well and the Saturn-5 is cleared for manned launchings, astronauts James McDivitt, David Scott and Russell Schweickart will ride a Saturn-5 into Earth orbit two or three months later to conduct flight test of the lunar module.

Following the return of Apollo-6, Apollo Programme Director Samuel C. Phillips said, “there's no question that it's less than a perfect mission”, although the Saturn-5’s demonstration of its ability to reach orbit despite the loss of two engines, was “a major unplanned accomplishment”. However, Marshall Space Flight Centre Director Wernher von Braun has recognised that the “flight clearly left a lot to be desired. … We just cannot go to the Moon [with this problem],” referring to the extreme pogo experienced on the flight. This means that solving the pogo phenomenon is now a major priority for NASA in order to keep the Apollo program on track and bolster confidence in the Saturn-5 vehicle. Can they do it? 








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Science / Space Race

[January 24, 1968] On Track for the Moon (Apollo 5 and Surveyor 7]

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by Kaye Dee

As we approach the first anniversary of the shocking loss of the crew of Apollo 1, the success of the recent Apollo 5 mission reminds us that the spirit of Grissom, White and Chaffee lives on as NASA continues developing and testing the technology to make a manned lunar landing a reality.

Apollo 1's Legacy
Although the fire that engulfed Apollo 1 and killed its crew destroyed its Command Module, the accident took place on the launchpad during a launch simulation, and fortunately the Saturn IB booster intended to loft that mission into orbit remained undamaged. Because that AS-204 vehicle was the last Saturn IB with full research and development instrumentation, NASA decided that this rocket would be re-assigned to Apollo 5, the much-delayed first test flight of the Lunar Module – the spacecraft essential for successfully landing astronauts on the Moon – while manned Apollo missions continue on hold.

From LEM to LM
The spacecraft we now call the Lunar Module (LM) became part of the Apollo programme in 1962, when NASA decided to adopt the technique of lunar orbit rendezvous (LOR) for its Moon landing missions. First proposed in 1919 by Ukrainian engineer and mathematician Yuri Kondratyuk, the LOR technique uses two spacecraft that travel together to the Moon and then separate in lunar orbit, with a lander carrying astronauts from orbit to the Moon’s surface. The LOR method allows the use of a smaller and lighter lander than the large, all-on-one spacecraft originally proposed for Apollo, and also provides for greater flexibility in landing site selection.

An early diagram comparing the size of a lunar landing vehicle using the Direct Ascent method of reaching the Moon and a LOR lunar excursion vehicle

The version of lunar orbit rendezvous suggested to NASA by engineer John C. Houbolt called for a landing vehicle consisting of two parts: a landing stage, that would accomplish the descent from orbit and remain on the Moon’s surface, and an ascent stage that would carry the astronauts back to the main spacecraft in orbit. This design gave us the Command Service Module as the Moon orbiting spacecraft, and what was originally called the Lunar Excursion Module (LEM, pronounced as a word, not as the individual letters) as the vehicle that would land astronauts on the Moon.

Dr. Houbolt illustrating the main spacecraft needed for his Lunar Orbit Rendezvous proposal for the Apollo programme

In June 1966, NASA changed the name to Lunar Module (LM), eliminating the word “excursion”. My friends at the WRE tell me that this was because there were concerns that using “excursion” might make it sound like the lunar missions were frivolous, and so reduce support for the Apollo programme! Despite the official name change, the astronauts, as well as staff at Grumman, still call it “the lem”, which certainly feels easier to say.

Delays…Delays…
However, the two-stage LEM/LM has proved much harder to develop and manufacture than the contractor Grumman originally anticipated, because of the complexity and level of reliability required of the hardware. Originally, NASA planned for the automated test flight of LM-1, the first Lunar Module, to occur in April 1967, but the delivery of the spacecraft was repeatedly delayed: the two stages of LM-1 did not arrive at Cape Kennedy until late June last year.

The separately-crated stages of LM-1 arriving at Kennedy Space Centre on board a Super Guppy cargo plane. The stages were mated to each other four days later

A team of 400 engineers and technicians then checked out the spacecraft to ensure that it met specifications. The discovery of leaks in the ascent stage propulsion system meant that the ascent and descent stages were demated and remated multiple times for repairs between August and October. LM-1 was finally mounted on its Saturn IB booster on 19 November and a launch date was set for the latter part of January 1968.

LM-1, encased in its SLA, being hoisted up for mounting on its launch vehicle

Lift Off at Last!
Although the launch was delayed for 10 hours when the countdown was held up by technical difficulties, Apollo 5 finally lifted off on 22 January 1968 (23 January for us here in Australia). The mission was designed to test the LM's descent and ascent propulsion systems, guidance and navigation systems, and the overall structural integrity of the craft. It also flight tested the Saturn V Instrument Unit.

Because they would not be needed during the Apollo 5 test flight, LM-1 had no landing legs, which helped to save weight. NASA also decided to replace the windows of LM-1 with aluminium plates as a precaution, after one of the windows broke during testing last December. Since the mission was of short duration, only some of LM-1’s systems were fully activated, and it only carried a partial load of consumables. 

LM-1's "legless" configuration is clearly seen in this view of it during checkout at Kennedy Space Centre

The Apollo 5 flight did not include Command and Service Modules (CSM), or a launch escape tower, so pictures of the launch vehicle show it to look more like its predecessor AS-203 than AS-202, which tested the CSM. The Apollo 5 stack had an overall height of 180ft and weighed 1,299,434 lbs. The LM was contained within the Spacecraft Lunar Module Adapter (SLA), located just below the nose cap of the rocket. The SLA consists of four panels that open like petals once the nose cap is jettisoned in orbit, allowing the LM to separate from the launcher.

The Saturn IB worked perfectly, inserting the second stage and LM into an 88-by-120-nautical-mile orbit. After the nose cone was jettisoned, LM-1 coasted for 43 minutes 52 seconds, before separating from the SLA into a 90-by-120-nautical-mile orbit. NASA’s Carnarvon tracking station in Western Australia tracked the first six orbits of the mission, while the new Apollo tracking station at Honeysuckle Creek, near Canberra, followed LM-1’s first orbit.

Putting LM-1 Through its Paces
Since it had no astronaut crew, the LM-1 test flight had a mission programmer installed, which could control the craft remotely. The first planned 39-second descent-engine burn commenced after two orbits, only to be aborted by the Apollo Guidance Computer after just four seconds, as the spacecraft was not travelling at its expected velocity. Exactly why this occurred is now being investigated. Of course, if there had been a crew onboard, the astronauts would probably have been able to analyse the situation and decide whether the engine should be restarted.

Instead, Mission Control, under Flight Director Gene Kranz, decided to conduct the engine and "fire-in-the-hole" tests under manual control, as without these test firings the mission would be deemed a failure. The "fire in the hole" test verified that the ascent stage could fire while attached to the descent stage, a procedure that will be used to launch from the Moon’s surface, or in the event of an aborted lunar landing. It involves shutting down the descent stage, switching control and power to the ascent stage, and firing the ascent engine while the two stages are still mated.

Apollo 5 Flight Director Gene Kranz (right) with future Lunar Module crew Astronauts McDivitt (left) and Schweickart (centre) discussing LM-1's control issues

Both the ascent and descent engines were fired multiple times during the flight to demonstrate that they could be restarted after initial use. Eight hours into the mission, a problem with the guidance system did cause the ascent stage to spin out of control, but the vital engine test burns had been completed by then. LM-1 also demonstrated its ability to maintain a stable hover, and the guidance and navigation systems controlled the spacecraft's attitude and velocity as planned.

At the conclusion of the flight testing, the separated ascent and descent stages were left in a low orbit, with the anticipation that atmospheric drag would naturally cause their orbits to decay so that the craft would re-enter the atmosphere. The ascent stage re-entered and was destroyed on 24 January, but as I write the descent stage is still in orbit.

Another Step on the Road to the Moon
NASA considers that the LM performed well during its test flight, and have deemed Apollo 5 a success. One wonders now if the second unmanned test flight with LM-2, planned for later this year, will need to go ahead. NASA also plans to return astronauts to space with a test flight of the redesigned Command Module in September this year. Once that goal is accomplished, every part of the Apollo system will have been tested in spaceflight and it will finally be “Go!” for astronauts to shoot for the Moon. I can’t wait!

Lunar map showing the landing sites of all the successful Surveyor missions

So Long Surveyor!
As the Apollo programme powers forward, the last of NASA’s automated lunar exploration programmes is coming to an end, with Surveyor 7 now in operation on the Moon. The Surveyor project was developed with the goal of demonstrating the feasibility of soft landings on the Moon's surface, ensuring that it would be safe for Apollo crews to touch down in their Lunar Modules. The Surveyor landings have complemented the Lunar Orbiter programme (which drew to a close in the latter part of last year), which imaged the Moon from orbit, mapping the lunar surface and providing detailed photographs of many proposed Apollo landing sites.

Making It Safe for a LM Landing
Of the seven Surveyor missions, five achieved their objectives, returning valuable data and images from the lunar surface. Surveyor 1, launched on 30 May (US time) in 1966, was the first American spacecraft to soft land on the Moon (following the successful landing of the USSR’s Luna 9 on 31 January that year), returning 11,237 images of the lunar surface. Unfortunately, its successor, Surveyor 2, failed in September 1966, impacting onto the lunar surface when a malfunction of the guidance system caused an error in the mid-course correction as it travelled to the Moon.

Surveyor 1's panorama of the lunar surface, which captured its shadow, cast by the light of the Earth

Surveyor 3, which lifted off on 17 April 1967, was the first to conduct in-situ experiments on the lunar soil, using its extendable arm and scoop. The spacecraft also returned over 6,000 images, including the famous "Surveyors Footprint" shot, showing its footpad on the lunar surface. The probe had a lucky escape as it tried to land: a problem with its descent radar caused the descent engine to cut off late, resulting in the lander bouncing twice on the lunar surface before settling down to a final safe landing!

Surveyor 3's footprint and footpad on the lunar surface, showing how it bounced on landing. The extendable arm and scoop are visible on the left of the picture

Just three months later, in July, Surveyor 4 was not so lucky. After a textbook flight to the Moon, contact was lost with the spacecraft just 2.5 minutes before touchdown in the Sinus Medii (Central Bay) region and it crashed onto the lunar surface. It’s believed that the solid-fuel descent engine may have exploded.

Launched on 8 September, Surveyor 5 also encountered engine problems on descent to the lunar surface, with a leak in the spacecraft's thruster system. Fortunately, it survived to make a safe landing and returned over 20,000 photographs over three lunar days. Instead of a sampler arm, Surveyor 5 carried an alpha backscattering experiment, and had a bar magnet attached to one landing pad. It carried out the first off-Earth soil analysis and made one of the most significant finds of the Surveyor missions — that the Moon's surface is likely basaltic, and therefore suitably safe for human exploration.

Surveyor 5's alpha backscattering experiment, sometimes described as a chemical laboratory on the Moon

Surveyor 6 landed safely near the Surveyor 4 crash site in November 1967 carrying an instrument package virtually identical to Surveyor 5. The spacecraft transmitted a total of 30,027 detailed images of the lunar surface, as well as determining the abundance of the chemical elements in the lunar soil. As an additional experiment, Surveyor 6 carried out the first lift-off from the Moon. Its engines were restarted, lifting the probe 12 ft above the lunar surface, and moving it 8 ft to the west, after which it landed again safely, and continued its scientific programme. 

Surveyor 7 – a Last Hurrah!
The successful completion of the Surveyor 6 mission accomplished all the goals that NASA had set for the Surveyor programme as an Apollo precursor. The JPL Surveyor team therefore decided that for the final mission they would aim for a riskier landing site, in the rugged highlands near the Tycho Crater. The engineers gave Surveyor 7 a less than 50-50 chance of landing upright due to the rough terrain in the area!

Tycho crater was the challenging landing site for NASA's last Surveyor mission

Launched on 7 January, Surveyor 7 is the last American robot spacecraft scheduled to land on the Moon before the Apollo astronauts. Its instrument package combines all the experiments used by its predecessors, in order to determine if the rugged terrain would be suitable for a future Apollo landing site.

During its first lunar day, the spacecraft’s camera has returned more than 14,000 images, including some views of the Earth! One of Surveyor 7’s innovations is the use of mirrors to obtain stereoscopic lunar photos. Laser beams directed at the Moon from two sites in the United States have also been recorded by cameras aboard Surveyor 7.

A view of the Earth captured by Surveyor 7's camera

Getting a Scoop
Surveyor 7’s versatile soil mechanics surface sampler is a key instrument on this mission. Designed to pick up lunar surface material, it can move samples around while being photographed, so that the properties of the lunar soil can be determined. It can also dig trenches up to 18 inches into the lunar surface to determine its bearing strength and squeeze lunar rocks or clods. The sampler is a scoop with a container which can be opened or closed by an electric motor. The scoop has a sharpened blade and includes two embedded magnets, to search for ferrous minerals and determine the magnetic characteristics of the lunar soil. So far, the moveable arm and scoop have performed 16 bearing tests, seven trenching tests, and two impact tests.

Only a few Surveyor 7 pictures are currently available, but this view of Surveyor 3 digging a trench into the Moon's surface shows how the scoop carries out this task

The scoop is mounted below the spacecraft’s the television camera so that it can reach the alpha-scattering instrument in its deployed position and move it to another selected location. In fact, the scoop helped to free the alpha-scattering instrument when it failed to deploy on the lunar surface. It has also been used to shade the alpha-scattering instrument and move it to different positions to evaluation other surface samples. During 36 hours of operation between January 11 and January 23, 1968, the sampler has performed flawlessly. Soil analyses have been conducted, as well as experiments on surface reflectivity and surface electrical properties. 

Surveyor 7 is now “sleeping” through its first lunar night. If it survives this period of intense cold, hopefully it will continue to produce significant results during its next lunar day. But if it doesn’t, the scientists and engineers at NASA’s Jet Propulsion Laboratory are already describing the Surveyor programme as a “treasure house of information for landing a man on the Moon before the end of this decade”. This has to be a fitting epitaph for any space mission.








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Science / Space Race

[November 12, 1967] Still in the Race! (Apollo-4, Surveyor-6, OSO-4 and Cosmos-186-188)

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by Kaye Dee

As I noted in my previous article, October was such a busy month for space activity that I had to hold over several items for this month. But November has already provided us with plenty of space news as well. Even though both American and Soviet manned spaceflight is currently on hold while the investigations into their respective accidents continue, preparations for putting astronauts and cosmonauts on the Moon are ongoing and the Moon race is still on!

“Oh, it’s terrific, the building’s shaking!”

Opening the door to human lunar exploration needs an immensely powerful booster, and the successful launch of Apollo-4 a few days ago on 9 November has demonstrated that NASA has a rocket that is up to the task. Although the Saturn 1B rocket intended to loft Apollo Earth-orbiting missions has already been tested, Apollo-4 (also designated SA-501) marked the first flight of a complete Saturn V lunar launcher.

The sheer power of the massive rocket took everyone by surprise. When Apollo-4 took off from Pad 39A at the John F. Kennedy Space Centre, the sound pressure waves it generated rattled the new Launch Control Centre, three miles from the launch pad, causing dust to fall from the ceiling onto the launch controllers’ consoles. At the nearby Press Centre, ceiling tiles fell from the roof. Reporting live from the site, Walter Cronkite described the experience: “… our building’s shaking here. Our building’s shaking! Oh, it’s terrific, the building’s shaking! This big blast window is shaking! We’re holding it with our hands! Look at that rocket go into the clouds at 3000 feet! … You can see it… you can see it… oh the roar is terrific!”

Firing Room 1 in the Launch Control Centre at Kennedy Space Centre, under construction in early 1966. The Apollo-4 launch was controlled from here

Could it be that the sound of a Saturn V launch is one of the loudest noises, natural or artificial, ever heard by human beings? (Apart, perhaps, from the explosion of an atomic bomb?) I hope I’ll get the opportunity to hear, and see, a Saturn V launch for myself at some point in the future.

The Power for the Glory

Developed by Dr. Wernher von Braun’s team at NASA’s George C. Marshall Space Flight Centre, everything about the Saturn V is impressive. The 363-foot vehicle weighs 3,000-tons and the thrust of its first-stage motors alone is 71 million pounds! No wonder it rattled buildings miles away at liftoff!

The F-1 rocket motor, five of which power the Saturn V’s S1-C first stage, is the most powerful single combustion chamber liquid-propellant rocket engine so far developed (at least as far as we know, since whatever vehicle the USSR is developing for its lunar program could have even more powerful motors).

The launcher consists of three stages. The Boeing-built S1-C first stage, when fully fuelled with RP-1 kerosene and liquid oxygen, has a total mass of 4,881,000 pounds. Its five F-1 engines are arranged so that the four outer engines are gimballed, enabling them to turn so they can steer the rocket, while the fifth is fixed in position in the centre. Constructed by North American Aviation and weighing 1,060,000 pounds, the S-II second stage has five Rocketdyne-built cryogenic J-2 engines, powered by liquid hydrogen and liquid oxygen. They are arranged in a similar manner to the first stage engines, and also used for steering. The Saturn V’s S-IVB third stage has been built by the Douglas Aircraft Company and has a single J-2 engine using the same cryogenic fuel as the second stage. Fully fuelled, it weighs approximately 262,000 pounds. Guidance and telemetry systems for the rocket are contained within an instrument unit located on top of the third stage.

Soaring into the Future

This first Saturn V test flight has been tremendously important to the ultimate success of the Apollo programme, marking several necessary first steps: the first launch from Complex 39 at Cape Kennedy, built especially for Apollo; the first flight of the complete Apollo/Saturn V space vehicle; and the first test of Apollo Command Module’s performance re-entering the Earth's atmosphere at a velocity approximating that expected when returning from a lunar mission. In addition, the flight enabled testing of many modifications made to the Command Module in the wake of the January fire. This included the functioning of the thermal seals used in the new quick-release spacecraft hatch design.

 
Up, Up and Away!

Apollo-4 lifted off on schedule at 7am US Eastern time. Just 12 minutes later it successfully placed a Command and Service Module (CSM), weighing a record 278,885 pounds, into orbit 115 miles above the Earth. This is equivalent to the parking orbit that will be used during lunar missions to check out the spacecraft before it embarks for the Moon.

After two orbits, the third stage engine was re-ignited (itself another space first) to simulate the trans-lunar injection burn that will be used to send Apollo missions on their way to the Moon. This sent the spacecraft into an elliptical orbit with an apogee of 10,700 miles. Shortly afterwards, the CSM separated from the S-IVB stage and, after passing apogee, the Service Module engine was fired for 281 seconds to increase the re-entry speed to 36,639 feet per second, bringing the CSM into conditions simulating a return from the Moon.


An image of the Earth taken from an automatic camera on the Apollo-4 Command Module

After a successful re-entry, the Command Module splashed down approximately 10 miles from its target landing site in the North Pacific Ocean and was recovered by the aircraft carrier USS Bennington. The mission lasted just eight hours 36 minutes and 54 seconds (four minutes six seconds ahead of schedule!), but it successfully demonstrated all the major components of an Apollo mission, apart from the Lunar Module (which is still in development) that will make the actual landing on the Moon’s surface. In a special message of congratulations to the NASA team, President Johnson said the flight “symbolises the power this nation is harnessing for the peaceful exploration of space”.

Goodbye Lunar Orbiters…

While Apollo’s chariot was readied for its first test flight, NASA has continued its unmanned exploration of the Moon, to ensure a safe landing for the astronauts. In August, Gideon gave us an excellent summary of NASA’s Lunar Orbiter programme, the first three missions of which were designed to study potential Apollo landing sites. Lunar Orbiter-3, launched back in February this year, met its fate last month when the spacecraft was intentionally crashed into the lunar surface on 9 October. Despite the failure of its imaging system in March, Lunar Orbiter-3 was tracked from Earth for several months for lunar geodesy research and communication experiments. On 30 August, commands were sent to the spacecraft to circularise its orbit to 99 miles in order to simulate an Apollo trajectory.

Lunar Orbiter-3 image of the Moon's far side, showing the crater Tsiolkovski

Each Lunar Orbiter mission has been de-orbited so that it will not become a navigation hazard to future manned Apollo spacecraft. Consequently, before its manoeuvring thrusters were depleted, Lunar Orbiter 3 was commanded on 9 October to impact on the Moon, hitting the lunar surface at 14 degrees 36 minutes North latitude and 91 degrees 42 minutes West longitude. Co-incidentally, Lunar Orbiter-4, which failed back in July and could not be controlled, decayed naturally from orbit and impacted on the Moon on 6 October. Lunar Orbiter-5, launched in August, remains in orbit.

…Hello Surveyor 6

A month after the demise of the Lunar Orbiters, NASA’s Surveyor-6 probe has made a much softer landing on the lunar surface, achieving a “spot on” touchdown in the rugged Sinus Medii (Central Bay – it’s in the centre of the Moon's visible hemisphere) on 10 November (Australian time; 9 November in the US). This region is a potential site for the first Apollo landing, but since it appeared to be cratered and rocky, mission planners needed to know if its geological structure (different to the ‘plains’ areas where earlier Surveyor missions have landed) could support the weight of a manned Lunar Module.

Only an hour after landing safely, Surveyor-6 was operational and sent back pictures of a lunar cliff about a mile from its landing point, which has been described as “the most rugged feature we have yet seen on the Moon”. The first panoramas from Surveyor indicate that the landing site is not as rough as anticipated, and seems suitable for an Apollo landing.

Deep Space Network stations in Australia are helping to support the Surveyor-6 mission, as well as Surveyor-5, that landed in the Mare Tranquilitatis (Sea of Tranquillity) in September and is still operational. Hopefully both spacecraft will survive the next lunar night, commencing two weeks from now. NASA plans to send one more Surveyor probe to the Moon, in January, so look out for a review of the completed Surveyor programme early next year.

Watching the Sun for Astronaut Safety

With the Sun moving towards its maximum activity late next year or early in 1969, and likely to still be very active when the Apollo landing missions are occurring (assuming that the programme resumes some time within the next 12 months), NASA has wasted no time in launching another spacecraft in its Orbiting Solar Observatory (OSO) series, to help characterise the effects of solar activity in deep space. A NASA spokesman was recently quoted as saying that “A study of solar activity and its effect on Earth, aside from basic scientific interest, is necessary for a greater understanding of the space environment prior to manned flights to the Moon”.

OSO-4 under construction

Launched on 18 October, OSO-4 (also known as OSO-D) is the latest satellite developed under the leadership of Dr. Nancy Grace Roman, NASA’s first female executive, who is Chief of Astronomy and Solar Physics. The satellite is equipped to measure the direction and intensity of Ultraviolet, X-ray and Gamma radiation, not just from the Sun, but across the entire celestial sphere.

The OSO-4 spacecraft, like its predecessors, consists of a solar-cell covered “sail” section and a “wheel” section that spins about an axis perpendicular to the pointing direction of the sail. The sail carries a 75 pound payload of two instruments that are kept pointing on the centre of the Sun. The wheel carries a 100 pound payload of seven instruments and rotates once every two seconds. This rotation enables the instruments to scan the solar disc and atmosphere as well as other parts of the galaxy. The satellite’s extended arms give it greater axial stability.

Hopefully, OSO-4 will have a long lifespan, producing data as solar activity increases across the Sun’s cycle, and enhancing safety for the Apollo and Soviet crews who will venture beyond the protection of the van Allen belts on their way to the Moon.

What are the Soviets Up To?

The USSR has been remarkably quiet about its manned lunar programme. One could almost think that they had given up racing Apollo to the Moon, if not for the rumours and hints that constantly swirl around. Rumours abounded at the time of the tragically lost Soyuz-1 mission that it was intended to be a space spectacular, debuting in the Soyuz a new, much larger spacecraft which would participate in multiple rendezvous and docking manoeuvres, and possibly even crew transfers, with one or more other manned spacecraft.

Such a space feat has yet to occur, but the mysterious recent space missions of Cosmos-186 and 188 suggest that the Soviets have something of the sort in mind for the future, and are still quietly working to develop the techniques that they will need for lunar landing missions and/or a space station programme.

It Takes Two to Rendezvous

On 27 October, Cosmos-186 was launched into a low Earth orbit, with a perigee of 129 miles and an apogee of 146 miles and an orbital period of 88.7 minutes. Cosmos-187 was launched the following day, and there has been speculation that it was intended to be part of a rendezvous and docking demonstration with Cosmos-186 but was placed into an incorrect orbit. However, as is so often the case with Cosmos satellites, the Soviet authorities only described their missions as continuing studies of outer space and testing new systems, so the actual purpose of this mission remains a mystery.


A rare Soviet illustration of what is believed to be the Cosmos-186-188 docking

However, Cosmos-186 was joined by a companion on 30 October, when Cosmos-188 was placed into a very similar orbit with a separation of just 15 miles. This clearly demonstrates the precision with which the USSR can insert satellites into orbit. The two spacecraft then proceeded to perform the first fully automated space docking (unlike the manual dockings performed by Gemini missions from Gemini-8 onwards), just an hour after Cosmos-188 was launched. Soviet sources, and some electronic eavesdropping by the now-famous science class at Kettering Grammar School in England, using surprisingly unsophisticated equipment, indicate that Cosmos-186 was the ‘active’ partner in the docking. It used its onboard radar system to locate, approach and dock with the ‘passive’ Cosmos-188.

While the two spacecraft were mechanically docked, it seems that an electrical connection could not be made between them, and no other manoeuvres appear to have been carried out while Cosmos-186 and 188 were joined together. Perhaps there were technical issues surrounding the docking, but an onboard camera on Cosmos-186 did provide live (if rather low quality) television images of the rendezvous docking and separation, and some footage was publicly broadcast.

After three and a half hours docked together, the two satellites separated on command from the ground and continued to operate separately in orbit. Cosmos-186 made a soft-landing return to Earth on 31 October, lending credence to the speculations that it was testing out improvements to the Soyuz parachute system, while Cosmos-188 reportedly soft-landed on 2 November.

Speculating on Soviet Space Plans

Was Cosmos-186 a Soyuz-type vehicle, possibly testing out modifications made to prevent a recurrence of the re-entry parachute tangling that apparently led to the loss of Soyuz-1 and the death of Cosmonaut Komarov? Building on speculations from the time of the Soyuz-1 launch, there have even been suggestions that Cosmos-186, while unmanned, was a spacecraft large enough to hold a crew of five cosmonauts. There is also speculation that Cosmos-188 may have been the prototype of a new propulsion system for orbital operations. Does this mean, then, that the USSR is planning some kind of manned spaceflight feat in orbit to celebrate the 50th anniversary of the Communist Revolution? Or that it will soon attempt a circumlunar flight, to reach the Moon ahead of the United States?

Whatever their future plans may be, the automated rendezvous and docking of two unmanned spacecraft in Earth orbit shows that the USSR’s space technology is still advancing rapidly. The joint Cosmos 186-188 mission proves that it is possible to launch small components and assemble them in space to make a larger structure, even without the assistance of astronauts. This means that massive rockets like the Saturn V might not be required to construct space stations in orbit, or even undertake lunar missions, if the project is designed around assembling the lunar spacecraft in Earth orbit. Has the Cosmos 186-188 mission therefore been a hint of what the USSR's Moon programme will look like, in contrast to Apollo? Only time will tell…


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Science / Space Race

[October 28, 1967] Unveiling Venus – at Least a Little (Venera-4 and Mariner-5)

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by Kaye Dee

Despite the hiatus in manned spaceflight missions while the Apollo-1 and Soyuz-1 accident investigations continue, October has been a very busy month for space activities – so much so that I’ve had to defer writing about some of this month’s events to an article next month!

Spaceflight Slowdown?

4 October saw the tenth anniversary of the launch of Sputnik-1, the Soviet satellite that surprised the world and ushered in the Space Age and the Space Race. Since that first launch, the pace of space exploration has been breathtaking, far surpassing what even its most ardent proponents in the 1950s anticipated.

In the famous Colliers’ “Man Will Conquer Space Soon” article series, reproduced even here in Australia, Dr Wernher von Braun predicted that the first manned mission to the Moon would not occur until the late 1970s

As part of the USSR’s Sputnik 10th anniversary celebrations, many space-focussed newspaper articles were published.  One of these, written by Voskhod-1 cosmonaut and engineer Dr. Konstantin Feoktistov, strongly hinted that Russia's next major space feat would be the launch of an orbiting space platform. This would certainly be an important development in establishing a permanent human presence in space and put the Soviet Union once again ahead in the Space Race, especially if the US and USSR lunar programmes are faltering.

Earlier this month, the head of the NASA, Mr James Webb, said it was increasingly doubtful that either the United States or the Soviet Union would land people on the Moon in this decade. He delivered a gloomy prognostication for the second decade of the Space Age, saying the entire US programme was “slowing down”. Mr. Webb criticised recent Congressional cuts of 10 per cent to the space-agency budget projected for the year ending next 30 June, saying that NASA was laying off over 100,000 people.

Administrator Webb also cast doubt on some proposed NASA planetary exploration missions. “The serious question is whether or not this country wants to start a Voyager mission to Mars in 1968”, he is reported to have said. The Voyager programme is a 10-year project that envisages sending two spacecraft to Mars (one to orbit around it, the other to land on its surface), with the additional possibility of landing a spacecraft on Venus and exploring Jupiter. These would undoubtedly be exciting missions that would reveal new knowledge about these planets, but Mr Webb said he had virtually no money for the Voyager programme as a result of the budget cut.

Parallel Planetary Probes: Venera-4 and Mariner-5

But possible future downturns in space activity can’t detract from this month’s big news: the safe arrival of two spacecraft at Venus!

Back in June, a suitable launch window meant that both the USSR and NASA sent spacecraft on their way to our closest planetary neighbour. First off the blocks was the Soviet Union, which launched its Venera-4 mission (generally known in the West as Venus-4) on 12 June from the Baikonur Cosmodrome in Kazakhstan. NASA’s Mariner-5 followed two days later, on 14 June, launched from Cape Kennedy.

Pre-launch photo of Venera-4

Venera-4 is the most recent Soviet attempt to reach the planet after Venera-2 and 3 failed to send back any data in March last year. There is some speculation that, since its previous Venus mission employed twin spacecraft, Russia may have also intended this Venus shot to be a two-spacecraft mission. It’s possible that the short-lived Cosmos 167 spacecraft, launched on 17 June, was Venera-4’s twin that failed to leave orbit, although with the secrecy that surrounds so much of the Soviet space program, who knows if we’ll ever get the truth of it? Venera-4 was itself first put into a parking orbit around the Earth before being launched in the direction of Venus. A course correction was performed on 29 July, to ensure that the probe would not miss its target.


Mariner-5 being prepared for launch

Mariner-5 is NASA’s first Venus probe since Mariner-2 in 1962. Originally constructed as a backup for the Mariner-4 Mars mission, that probe’s success meant that the spacecraft could be repurposed to take advantage of the 1967 Venus launch window. Interestingly, I understand from my friends at the Sydney Observatory that there were initial suggestions to send the Mariner back-up spacecraft to either comet 7P/Pons–Winnecke or comet 10P/Tempel, before the Venus mission was decided upon. While it’s useful to have additional data from Venus, it would have been fascinating to send an exploratory mission to a comet, since we know so little about these transient visitors to our skies. 

At its closest, Venus is just 36 million miles from Earth, but Mariner-5 followed a looping flightpath of 212 million miles, to enable it to fly past Venus at a distance of around 2,500 miles (about 10 times closer than Mariner-2’s flyby). Australia’s Deep Space Network (DSN) stations at Tidbinbilla, near Canberra, and Island Lagoon, near the Woomera Rocket Range, were respectively the prime and back-up monitoring and control stations for Mariner-5’s mid-course correction burn that placed it on its close flyby trajectory. 

Keys to Unlock a Mystery

Venus has always been a planet shrouded in mystery since its thick, cloudy atmosphere prevents any telescopic observation of its surface. For this year’s launch window, one could almost believe that Cold War tensions had been overcome and the USSR and USA had agreed to work together on a Venus exploration program, given that their two spacecraft effectively complement each other.

Venera-4’s mission was announced as “direct atmospheric studies”, with Western scientists speculating that this meant that it would follow Venera-3 in attempting to land on the planet’s surface. The spacecraft’s arrival at Venus has proved this speculation to be correct, and the few images of Venera-4 now available show the 2,436 lb spacecraft to be near-identical to Venera-3. 11 ft high, with its solar panels spanning 13 ft, Venera-4 carried a 1 metre (3 ft 3 in) spherical landing capsule that was released to descend through the atmosphere while the main spacecraft flew past Venus and provided a relay station for its signals.
Soviet models of the Venera-4 spacecraft and its descent capsule

The 844 lb descent capsule was equipped with a heat shield, capable of withstanding temperatures up to 11,000°C (19,800 °F) and had a rechargeable battery providing 100 minutes of power for the instruments and transmitter. During the flight to Venus the battery was kept charged by the solar panels of the carrier spacecraft. Supposedly, the entire Venera-4 probe was sterilised to prevent any biological contamination of Venus, but some Western scientists have cast doubt on this claim. The capsule was pressurized up to 25 atmospheres since the surface pressure on Venus was unknown until Venera-4’s arrival.
Picture of the Venera-4 descent capsule released by the USSR. Western scientists are wondering what that heat shield is made of

Information recently released by the Soviet Academy of Sciences has said that the descent vehicle carried two thermometers, a barometer, a radio altimeter, an atmospheric density gauge, 11 gas analysers, and two radio transmitters. Scientific instruments on the main body of the spacecraft included a magnetometer and charged particle traps, both for measuring Venus' magnetic field and the stellar wind on the way to Venus, an ultraviolet spectrometer to detect hydrogen and oxygen gases in Venus' atmosphere, and cosmic ray detectors.


Much smaller than Venera-4, the 5401b Mariner-5 was designed to flyby Venus taking scientific measurements: it was not equipped with a camera, as NASA considered this un-necessary in view of the planet’s cloud cover. NASA controllers initially planned a distant flyby of Venus, to avoid the possibility of an unsterilised spacecraft crashing into the planet, but the final close flyby was eventually chosen to improve the chances of detecting a magnetic field and any interaction with the solar wind.

As Mariner-4’s backup, Mariner-5 has the same basic body – an octagonal magnesium frame 50 in diagonally across and 18 in high. However, since it was heading to Venus instead of Mars, Mariner-5 had to be modified to cope with the conditions much closer to the Sun. Due to its trajectory, Mariner-5 needed to face away from the Sun to keep its high-gain antenna pointed at Earth. Its solar panels were therefore reversed to face aft, so they could remain pointed at the Sun. They were also reduced in size, since closer proximity to the Sun meant less solar cells were needed to generate the same level of power. Mariner-5's trajectory also required the high-gain antenna to be placed at a different angle and made moveable as part of the radio occultation experiment. A deployable sunshade on the aft of the spacecraft was used for thermal control, and Mariner-5 was fully attitude stabilized, using the sun and Canopus as references.
View from below showing the main components of Mariner-5

Mariner-5’s prime task was to determine the thickness of Venus’ atmosphere, investigate any potential magnetic field and refine the understanding of Venus’ gravity. Its suite of instruments included: an ultraviolet photometer, a two-frequency beacon receiver, a S-Band radio occultation experiment, a helium magnetometer, an interplanetary ion plasma probe and a trapped radiation detector. The spacecraft instruments measured both interplanetary and Venusian magnetic fields, charged particles, and plasmas, as well as the radio refractivity and UV emissions of the Venusian atmosphere.

During its 127-day cruise to Venus, Mariner-5 gathered data on the interplanetary environment. In September and October, observations were co-ordinated with measurements made by Mariner-4, which is on its own extended mission, following its 1965 encounter with Mars. Similar observations were made by Venera-4 during its flight to Venus, which found that the concentration of positive ions in interplanetary space is much lower than expected. 

Missions Accomplished

A few days before it arrived at Venus, the Soviet Academy of Sciences requested assistance from the massive 250 feet radio telescope at the Jodrell Bank Observatory in the UK, asking the facility to track Venera-4 for the final part of its voyage. This has provided Western scientists with some independent verification of Soviet claims about the mission. Jodrell Bank even announced the landing of the Venera-4 descent capsule more than seven hours before it was reported by the Soviet news agency Tass!

On 18 October, Venera-4’s descent vehicle entered the Venusian atmosphere, deploying a parachute to slow its fall onto the night side of the planet. According to a story that one of the Sydney Observatory astronomers picked up from a Soviet colleague at a recent international scientific conference, because there was still the possibility that, beneath its clouds Venus might be largely covered by water (one of the main theories about its surface), the capsule was designed to float if it did land in water. Uniquely, the spacecraft’s designers made the lock of the capsule using sugar, which would dissolve in liquid water and release the transmitter antennae in the event of a water landing.

Although the Venera-4 capsule had 100 minutes of battery power available and sent back valuable data as it fell through the atmosphere, Jodrell Bank observations, and the official announcement from Tass, indicated that the signal cut off around 96 minutes. While it was initially thought that this meant that the capsule had touched down on the surface, and there were even early reports claiming it had detected a rocky terrain, questions are now being raised as to whether it actually reached the surface, or if the spacecraft failed while still descending. Tass has said that the capsule stopped transmitting data because it apparently landed in a way that obstructed its directional antenna. A recording of the last 20 seconds of signal received at Jodrell Bank was delivered to Vostok-5 cosmonaut Valery Bykovsky during a visit to the radio telescope on 26 October. Perhaps once it is fully analysed, the question of the capsule’s fate will be clarified. Of course, if the landing is confirmed, Venera-4 will have made history with the first successful landing and in-situ data gathering on another planet.

Diagram illustrating the major milestones during the Mariner-5 encounter with Venus on 19 October
Mariner-5 swept past Venus on 19 October, making a close approach of 2,480 miles. At 02:49 GMT the Island Lagoon DSN station commanded Mariner 5 to prepare for the encounter sequence and 12 hours later its tape recorder began to store science data. Tracked by the new 200 in antenna at NASA’s Goldstone tracking station, Mariner reached its closest encounter distance at 17:35 GMT, and minutes later entered the “occultation zone” before passed behind Venus as seen from the Earth. 17 minutes later, Mariner-5 emerged from behind Venus and completed its encounter at 18:34 GMT.

The following day, Mariner-5 began to transmit its recorded data back to Earth. Over 72½ hours there were three playbacks of the data to correct for missed bits. Mariner-5's flight path following its Venus encounter is bringing it closer to the Sun than any previous probe and the intention is for to be tracked until its instruments fail.

A Peep Behind the Veil

So what have we learned about Venus from these two successful probes? There has long been controversy among astronomers as to whether Venus is a desert planet, too hot for life, or an ocean world, covered in water. The data from both Venera and Mariner has come down firmly on the side of the desert world hypothesis.
Astronomical artist Mr. Chesley Bonestell's 1947 vision of a desert Venus

The effects of Venus’ atmosphere on radio signals during Mariner-5’s occultation experiment have enabled scientists to calculate temperature and pressure at the planet's surface as 980°F and 75 to 100 Earth atmospheres. These figures disagree with readings from Venera 4 mission, which indicate surface temperatures from 104 to 536°F and 15 Earth atmospheres’ pressure, but both sets of data indicate a hellish world, with little evidence of water and an extremely dense atmosphere.

Venera has established that Venus’ atmosphere consists almost exclusively of carbon dioxide with traces of hydrogen vapour, very little oxygen, and no nitrogen. Mariner-5's data indicates that the atmosphere of Venus ranges from 52 to 87 per cent carbon dioxide, with both hydrogen and oxygen in the upper atmosphere: it found no trace of nitrogen. It detected about as much hydrogen proportionately as there is in the Earth's atmosphere. Mariner scientists, however, have pointed out that further analysis and refinements of both Russian and American data could clear up the apparent discrepancies.

Although Mariner’s instruments could not penetrate deeply enough into Venus’ atmosphere to obtain surface readings, they determined that the outer fringe of the atmosphere, where atoms were excited by direct sunlight, had a temperature of 700°F, below which was a layer close to Zero degrees, lying about 100 miles above the surface. Chemicals in the atmosphere, or electrical storms far more intense than those of Earth, give the night side of the planet an ashen glow.
A view of the Mariner-5 control room at JPL during the Venus encounter

A fascinating finding is that the dense atmosphere acts like a giant lens, bending light waves so they travel around the planet. Both American and Russian researchers agree that astronauts standing on the surface would feel like they were “standing at the bottom of a giant bowl”, with the back of their own heads a shimmering mirage on the horizon. Vision would be so distorted that the sun would appear at sunset to be a long bright line on the horizon: its light could penetrate the atmosphere, but not escape because of scattering, so that it would appear as a bright ball again for a time at sunrise until the atmosphere distorted its rays.

Neither spacecraft found any evidence of radiation belts comparable to the Van Allen belts around the Earth, and both established that Venus has only a very slight magnetic field, less than 1% that of the Earth. Observing how much Venus' gravity changed Mariner 5's trajectory established that Venus’ mass is 81.5 % that of Earth. Tracking of radio signals from Mariner-5 as it swept behind Venus, has shown that the planet is virtually spherical, compared with Earth's slightly pear-shape. (Other celestial mechanics experiments conducted with Mariner-5 obtained improved determinations of the mass of the Moon, of the astronomical unit, and improved ephemerides of Earth and Venus).

Life on Venus?

Although neither spacecraft was equipped to look for life on Venus, their findings will undoubtedly contribute to the growing scientific controversy over whether life does, or can, exist there. Based on its Venera results, the Soviet Union has said that Venus is “too hot for human life”, although Sir Bernard Lovell, the Director of Jodrell Bank Station, has suggested that future probes might find remnants of some early organic development, even if conditions today make life highly unlikely. However, German/American rocket pioneer and space writer Dr Willy Ley, has suggested there might be the possibility of “a very specialised kind of life on Venus”, possibly at the poles, which he believes would be cooler that the currently measured temperatures. The USSR’s Dr Krasilnikov has said that Earth bacteria could withstand the atmospheric pressure on Venus and might even be able to survive the intense heat. 


But just as Mariner-4 demolished fantasies of canals made by intelligent Martians, so the results from Venera-4 and Mariner-5, in allowing us a glimpse behind its cloudy veil, have swept aside any number of science fiction visions of Venus. Edgar Rice Burroughs’ verdant Amtor, with its continents and oceans, and Heinlein’s swampy Venus are no more. They have been replaced by a new vision of a hellish Venus, almost certainly inimical to life, with fiery storms raging in a dense, metal melting atmosphere which traps and bends light waves in a weird manner. I wonder where the SF writers of the future will take it?



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Science / Space Race, Uncategorized

[August 24, 1967] Up and Around (Lunar Orbiter)

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by Gideon Marcus

Wall to Wall Coverage

When President John F. Kennedy, on May 4, 1961, commited the United States to "achieving the goal, before this decade is out, of landing a man on the Moon and returning him safely to the Earth," he initiated not one, but several parallel endeavors.

To land a man on the Moon requires not just a spaceship, a rocket, and the infrastructure to support them, it requires reconnaissance.  When the President made that speech, the closest photographs of the lunar surface had been taken from 250,000 miles away.  The smallest details our 'scopes could make out at the time were about a quarter mile wide.  This is fundamentally useless when trying to determine whether a given site is flat enough to be suitable for landing a spacecraft.  Guessing the height of lunar mountains from their shadows at such resolution was similarly impossible.  Who knew how many hidden peaks lurked to snag Apollo astronauts on their way down?

Project Ranger was NASA's first major lunar project, each spacecraft taking pictures of the Moon before crashing into it. Three successful missions achieved resolutions as sharp as a foot and a half.  Good enough, resolution-wise, but can you imagine having to send a Ranger for any one of dozens of potential landing sites?  The cost would be prohibitive.  Ranger's follow-up, the soft-landing Surveyor was able to determine if the lunar surface could be landed on, but it was no better at mapping the Moon than Ranger.


Potential Apollo site areas

As early as 1960, NASA knew it would need an orbiting spacecraft if it was ever to thoroughly map the Moon.  There was Earthly precedent — the Discoverer spy satellite was at that time already taking high resolution photographs of the Earth for military surveillance purposes.  But getting a spacecraft all the way to the Moon, and it being able to provide footage of 99% of the lunar surface?  That was another kettle of fish.  That required a big rocket to carry a big satellite that could carry a big imaging system.  TV imaging was quickly discarded as being too bulky and low resolution.

In 1962, Space Technology Laboratories put forth an orbiter proposal that used a film system, with each frame to be imaged and transmitted back to Earth.  This was the first workable design, and combined with elements of an RCA proposal, NASA was able to officially solicit contractors for the project in mid-1963.  Ultimately, Boeing won the contract, in large part because of their design's use of Eastman Kodak's new dry film development system.  Their camera would be more reliable, lighter, and less susceptible to solar flares ruining the photos.

Like Scales Falling from the Eyes

It took more than two years of development, but by 1966, the 850 pound Lunar Orbiter was ready.  Using the same Atlas Agena as Ranger, the first spacecraft roared off to the Moon on August 10.  Despite some navigational failures and a bit of overheating, Lunar Orbiter 1 braked into lunar orbit on August 14.  The next day, the spacecraft began sending back pictures–not of the Moon, but of previously developed images, to test the system.

Issues plagued the high-resolution camera system throughout the mission, smearing many of the photos.  But by August 29, Lunar Orbiter 1 was able to take 205 pictures of the Moon at altitudes ranging from 1000 to just 30 miles (no air means an orbit can be as low as you like), readout of which began August 30 and finished September 16.  All of the major Apollo landing sites were photographed, and at high contrast.  The cherry on top of the lunar sundae was this photograph of the Earth, the first taken from the vicinity of the Moon, and the longest distance snapshot of our home planet:

This did not mark the end of the first Lunar Orbiter's mission.  For the next six weeks, NASA continued to receive telemetry and data from the probe's micrometeor detectors (no hits recorded).  But by October 28, Lunar Orbiter was a sick ship, indeed, running low on stabilizing jet fuel, overheating, and losing power.  It was starting to broadcast erratically, which threatened to interfere with communications with the upcoming Lunar Orbiter 2.  So, on October 29, during its 577th orbit, Lunar Orbiter 1 was directed to impact with the Far Side of the Moon.

Two for Two

Just eight days later, on November 6, Lunar Orbiter 2 headed for the Moon.  Much of it had been painted black, which addressed the navigation issues (glare blotting out the guide star Canopus).  Overheating was avoided by frequent maneuvers to minimize exposure of heat-absorbing surfaces to the sun.  By November 18, the spacecraft was snapping perfect medium resolution (for broad range) and high res (for potential landing site) pictures of the Moon from a 30 mile orbit.  Mapping was done by the 26th and readout by December 7.  Among the most significant shots included one of the Ranger 8 impact site and another dramatic photograph of Copernicus crater:


(C1 is Ranger's impact crater)


Copernicus from the side

817 pictures were taken in all, only six of which were lost due a glitch in an amplifier on the final day of readout.  Lunar Orbiter 2 is still in orbit, returning data.  In fact, it was hit three times by micrometeors back in November, probably by the same cometary fragments that give us our annual Leonids meteor display.

Following Up

Lunar Orbiter 3, launched February 7, 1967, had a more refined mission than its predecessors.  Its job was to focus on promising sites its sisters had found rather than mapping willy nilly.  NASA engineers planned to closely study its orbit around the Moon for gravitational wiggles, thus making a map of the Moon's insides as well as its surface.

Unfortunately, while the spacecraft was shooting pictures, the film advance mechanism started to balk.  NASA terminated photography on February 23 after just 211 pictures.  On March 4, with 72 photos still left to be transmitted back to Earth, the film advance motor burned out.  Still, had NASA not stopped shooting pictures earlier, it is likely they would have lost all of the photos.

The shots they did get were unprecedentedly good, including this shot of the Surveyor 1 landing site:

Gilding the lily

At this point, the Lunar Orbiter program had already fulfilled its main requirement: documenting all possible Apollo landing sites.  Now it was time to push the system to its limits.  Lunar Orbiter 4 went up on May 4, 1967, beginning photography on the 11th.  The spacecraft immediately ran into trouble.  The thermal door that regulated camera temperature wasn't closing properly, letting light leak through.  This led to a scramble to test the problem on the ground.  Engineers were able to keep the door partially open, threading the needle between too much glare and dropping the temperature such that condensation fogged the film.  The readout encoder started going, too.  NASA cut off photography atfter 163 shots, but because the encoder was bleating erroneous signals, engineers had to work out a tedious, manual system for film advance and readout.  Still, they got it done by June 1, resulting in 99% coverage of the Moon's near side at ten times the resolution possible from Earth.  This revealed a bonanza of selenological detail.  Plus, 80% of the Moon's Far Side had now been mapped, too.

The last Lunar Orbiter went up on August 1 with a primarily scientific mission.  Shooting began August 6, and on August 8, the spacecraft took an historic shot of the full Earth:

All of the planned 212 shots were taken by August 18 covering five Apollo sites, 36 science sites, and 23 previously unphotographed sites on the lunar Far Side.  An unqualified success, the spacecraft will enter the next phase of its life this week, returning data on the lunar environment and gravitational field along with the still orbiting Lunar Orbiters 2 and 3 (contact with #4 was lost July 17).

Unprecedented

It was just a few years ago that it seemed the Moon was a curse.  Most of the early Pioneer probes failed, with only Pioneer 4 a real success.  Three our of nine Rangers were duds.  Along comes Lunar Orbiter, every mission of which was more or less a triumph.  The way has been paved for the first human beings to set foot on another world in a year or two.

But beyond that, real science has been done.  A few years back, my sister gave me a lovely 1963 map of the Moon, the most detailed possible at the time.  I can't wait for a new map, based on Lunar Orbiter pictures, to come out.

I know what I want for Hannukah this year!




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