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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

[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

[April 20, 1966] Space Exploration is Hard (Venera 2 and 3, Luna 10 and OAO 1)

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by Kaye Dee

While manned spaceflight always grabs the headlines, the past month or so has seen some fascinating, if not always successful, attempts at planetary and lunar exploration and the launch of a new space observatory. The failures of some of these missions remind us that space exploration is hard and success is never guaranteed…

Still Unable to Lift the Veil of Venus

Launched just days apart back in November last year, Soviet Venus probes, Venera 2 and 3 were due to arrive at the Earth’s mysterious, cloud-veiled sister planet at the beginning of March, but both seem to have failed just on the verge of success. 

As early as February 1961, the USSR commenced its attempts to explore Venus with the Venera (Russian for Venus) 1 probe. Although Venera-1 flew past Venus at a distance of 100,000km on 19 May 1961, no data were received, due to a communications failure. According to my friends at the Weapons Research Establishment, following that mission there may have been several failed attempts by the USSR to launch missions to Venus, before Venera 2 and 3 were successfully sent on their way back in November.

(top) Venera 1, the USSR's first Venus probe and (bottom) its official follow on, Venera 2. I wonder how many unannounced failures lie between these two missions?

According to various news releases from the Soviet news agency TASS, the two spacecraft were intended for different exploration missions. Venera 2 was planned to fly past the sunlit side of Venus and examine its enigmatic clouds. The spacecraft was equipped with cameras, a magnetometer and a variety of instruments to measure the radiation environment in space and at Venus. Valuable data on the interplanetary space environment was transmitted back to Earth during the flight to Venus.

All Venera 2's instruments were activated for the flyby on 27 February, at a distance of 14,790 miles. While the instruments were operating, the radio had to be shut down, with the probe storing their data in onboard recorders. The plan was for the stored data to be transmitted it to Earth once contact was restored. However, it seems that ground controllers in the USSR were unable to re-establish communications with the spacecraft after the flyby. Attempts to re-establish contact with Venera 2 ceased on March 4, but if communication with the spacecraft can be made at some future point, Soviet scientists believe that it may still be possible to recover some of the flyby data.

Touchdown?

Unlike Venera 2’s flyby (similar to those of Mariner 2 at Venus and Mariner 4 at Mars), Venera 3’s ambitious goal was to land a small capsule of instruments on the surface of Venus, hopefully to unlock at least some of the secrets hidden beneath its veil of clouds. Because some scientists believe there could be life on Venus, the USSR claims the lander was “sterilised” before its departure from Earth so that would not contaminate the Venusian atmosphere or surface with any microbial terrestrial life.

The Venera 3 lander was a metal sphere about 35 inches in diameter, which carried instruments to measure atmospheric temperature, pressure and composition, and light levels at different altitudes, as well small metal Soviet emblems. Interestingly, because some scientists still hold the view that Venus could be a water world, the lander was designed to be able to float and carried a motion detector, which could determine if it had actually landed in water and was rocking in the waves.

Venera 3 was similar to its sister-probe Venera 2. But look closely and you can see the landing capsule at the bottom of the spacecraft

Weighing 884lbs, the lander was designed to drop through Venus’ atmosphere on a parachute, transmitting data from its instruments directly back to Earth, while the rest of the Venera 3 spacecraft went into orbit around Venus to take other scientific measurements. However, like its sister probe, contact with Venera 3 was lost as it approached Venus. Tracking data indicates that the landing capsule entered the Venusian atmosphere on 1 March, although no telemetry was received from the lander. Nevertheless, the Venera 3 lander has become the first manmade object to impact another planet, which is an achievement in itself. The reasons for the failure of the two Venera spacecraft remain a mystery, although some experts believe that the thick Venusian atmosphere may have had something to do with it.

Newly-released Venera 3 stamp (thanks Uncle Ernie!). It shows the Soviet medal and pendant depicting the planet Earth that were carried on board the lander

Advancing the Soviet Lunar Programme

Despite the problems with its Venus programme, the USSR’s lunar programme seems to be going from strength to strength. Following on from the historic soft landing on the Moon with Luna 9 in February, Luna 10 marks another step forward, becoming the first spacecraft to go into orbit around the Moon. (Of course, it’s obvious that this feat was timed to occur during the 23rd Congress of the Communist Party of the Soviet Union, but I’m sure it was also deliberately planned to upstage the United States’ Lunar Orbiter program, which is due to commence later this year, with a series of spacecraft that will photograph and map the Moon in advance of the Apollo programme).

Luna 10, the first spacecraft to orbit the Moon

A pre-launch photograph of Luna 10 indicates that its design is very similar to that of Luna 9, although the instrument capsule on top has a different shape. Launched on 31 March, Luna 10 went into lunar orbit three days later. Its elliptical orbit approaches as close as to the lunar surface as 217 miles, with its farthest point at 632 miles, and takes just under three hours. The 530lb spacecraft is battery powered, rather than using solar panels, so it is unclear how long it will keep sending data back to the Earth, but at present it is producing a regular stream of information about the space environment in the vicinity of the Moon, that will help us understand how safe (or otherwise) it will be for the first cosmonauts and astronauts to explore cislunar space and the Moon itself.

Close up view of a model of the Luna 10 instrument capsule and the small Soviet metal pendants that it carried onboard

Scientific Instruments aboard Luna 10 include a gamma-ray spectrometer, a magnetometer, a meteorite detector, instruments for solar-plasma studies, and devices for measuring infrared emissions from the Moon and radiation conditions of the lunar environment. However, it is not clear whether the probe is actually carrying a camera to photograph the Moon’s surface. Preliminary data released by the Soviet Union indicates that there are higher concentrations of meteoritic dust in the vicinity of the Moon than in interplanetary space, as well as “electron fluxes” that are “70 to 100 times more intense than the cosmic ray background”.

First day cover commemorating the Luna 10 mission. Soviet space covers are masterpieces of propaganda, with the stamp design, envelope design and postmark all re-inforcing the message of Communist space achievement!

A Propaganda Serenade from the Moon!

As the Space Race heats up, the Soviet leadership is always ready to exploit propaganda opportunities associated with space exploration. To celebrate the CPSU Congress, a synthesised version of the Communist anthem “The Internationale” was broadcast live from Luna 10 to the congress on 4 April. (At least, it was claimed to be live: I wonder if Luna 10’s controllers actually used a pre-recorded version in case there were problems with the spacecraft? After all, it would be very politically embarrassing to have a failure of Soviet technology at such a high profile event for global Communism!)

Sky High Eyes on the Sky

The last mission I want to mention this month is NASA’s Orbiting Astronomical Observatory (OAO) 1, not least because this a major space project managed by a woman! Dr. Nancy Grace Roman, formerly a radio astronomer with the Naval Research Laboratory, joined NASA in 1959 and became Chief of Astronomy in NASA's Office of Space Science in 1960. She has a prestigious international reputation and was the first woman in an executive position at the space agency, where she has established the space astronomy programme.

Dr Nancy Grace Roman in 1962 with a model of another of her space observatory projects, the Orbiting Solar Observatory

The heaviest satellite yet launched by the United States (weighing almost two tons), OAO 1 was launched successfully on 8 April, riding to orbit on an Atlas-Agena D from Cape Canaveral. It carried 10 telescopes and other instruments capable of detecting ultraviolet, X-ray and gamma ray emissions to measure the absorption and emission characteristics of the stars, planets, nebulae from the visible to gamma-ray regions The observatory satellite was intended to give astronomers their first clear look at the heavens without the distorting effect of the Earth’s atmosphere and its results were greatly anticipated.

However, before the instruments could be activated, something caused a power failure that resulted in the mission being terminated after just 20 orbits. Because the spacecraft could not be controlled, its solar panels could not be deployed to recharge the batteries supplying the equipment and instruments on board the satellite. Although this is a blow to space astronomy, I’m sure the OAO programme will continue as future satellites are already in development.

NASA illustration of Orbiting Astronomical Observatory 1. While this satellite has failed, there will be future space observatories in this program




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Science / Space Race

[August 30, 1965] 8 Days or Bust! (Gemini 5's epic space mission)

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by Kaye Dee

Mr. Barry McGuire should have waited another month to record his hit song Eve of Destruction. Why? Because then his telling line “You may leave Earth for four days in space, but when you return it’s the same old place” could have been made an even punchier by updating it with the latest space flight record of eight days, set by the crew of Gemini 5.


The Gemini 5 crew, Charles "Pete" Conrad (left) and mission commander Gordon "Gordo" Cooper (right), ready to set a new space endurance record

One for the Record Books

The safe return of the Gemini 5 crew yesterday, at the end of a mission dogged by technical problems, not only captured the record for the longest spaceflight to date, it has catapulted the United States into the lead ahead of the Soviet Union for the first time in the Space Race! From the outset, NASA planned for this mission to last eight days, to demonstrate that astronauts could live and work in space for the duration of an Apollo mission to the Moon and back. That this flight time beat the Soviet record of just under five days set by cosmonaut Valery Bykovsky in Vostok 5 in 1963, is a welcome added bonus. Other objectives of the mission included: demonstrating the guidance and control systems; evaluating the new fuel cell system and rendezvous radar; and testing the ability of the astronauts to manoeuvre close to another object.

A Mission Patch: the Start of a New Tradition?

For this crucial mission, NASA paired veteran Mercury astronaut Gordon Cooper, who flew America’s last and longest Mercury mission, with rookie Charles “Pete” Conrad, a member of the second group of astronauts selected in 1962. Because astronauts have been prohibited from naming their spacecraft (following NASA’s displeasure with the name Gus Grissom selected for Gemini 3), Cooper wanted to wear a mission insignia that would symbolise the purpose of their flight. He and Conrad designed a “mission patch”, along the lines of those worn by military units, showing a Conestoga wagon, the type of vehicle used by many of the pioneering families heading into the American West.


The Gemini 5 mission patch as Cooper and Conrad originally designed it, with its pioneer inspired motto (left), alongside the NASA-modified flight version on the right.

On their original design, the wagon carried a motto that was also derived from pioneering times: “8 Days or Bust”. But according to a rumour I’ve heard from my former WRE colleagues, NASA felt that this might leave the agency open to ridicule if the mission didn’t last that long. Because of this, the embroidered patches that Cooper and Conrad wore on their spacesuits during the flight had the ambitious slogan covered by a piece of cloth. But I like the idea of each mission having its own symbolic insignia, so I hope that mission patches become a tradition for future spaceflights.

Launching into History

Gemini 5 was originally supposed to launch on 19 August, but problems with the telemetry programmer and deteriorating weather delayed the lift-off until 21 August. Like previous Gemini missions, Cooper and Conrad lifted off from Launch Complex 39 at the Cape Kennedy Air Force Station. I understand that NASA will continue to use it for the rest of the Gemini programme while its new John F. Kennedy Space Centre is being constructed nearby for the Apollo missions.

During the launch, the astronauts experienced a type of vibration known as “pogo” (as in pogo stick!) which seems to have momentarily impaired their speech and vision. This will need to be further investigated to determine if it poses a threat to crew health and safety on future flights. After the launch, part of the Titan II launch vehicle's first stage was found floating on the surface of the Atlantic Ocean and retrieved; I expect it will go on display in a museum after it has been thoroughly studied.


Recovering the upper half of the Titan II launch vehicle first stage from the Atlantic Ocean

Dr. Rendezvous to the Rescue!

Just over 2 hours after launch, the Rendezvous Evaluation Pod (REP, nicknamed Little Rascal, I’m told) was ejected into orbit from Gemini 5. The crew were supposed to practice rendezvous techniques with this mini satellite. However, about 4 hours into the flight, very low oxygen pressure in one of the spacecraft’s fuel cells that provide onboard power led to a decision to shut both fuel cells down. Gemini 5 is the first mission to use this new method of generating onboard power, but without the fuel cells, the spacecraft has only a limited battery power reserve. As a result, Gemini 5 was powered down, drifting along in "chimp mode," without active control by the crew. It looked for a while as if the mission might be “2 days and bust”, but ground tests showed that the faulty fuel cell should work even with low oxygen pressure and both fuel cells were gradually put back into operation, enabling the mission to continue.


An artist's impression of the Gemini 5 Rendezvous Evaluation Pod, as the mission should have unfolded. Unfortunately, the battery on its flashing beacon, which helped the astronauts to see it against the blackness of space, died before the fuel cell issues were resolved.

The fuel cell failure meant that the REP experiment, and others, had to be scrapped. However, astronaut Edwin “Buzz” Aldrin devised a rendezvous simulation to test the Gemini 5 crew, which would require them to rendezvous with a specific point in space. The other astronauts don’t call Aldrin “Dr. Rendezvous” for nothing: he has a doctorate in Astronautics, specialising in orbital mechanics, from the Massachusetts Institute of Technology! The “phantom rendezvous” test took place on the third day of the mission. Cooper and Conrad proved that precision manoeuvres could be successfully accomplished, carrying out four different rendezvous manoeuvres using the Gemini’s Orbit Attitude and Manoeuvring System (OAMS).

On August 24 Cooper reached a cumulative total of 98 hours in space, over his two flights, taking the record for the longest time spent in space by an American astronaut. By the end of the mission he was the world record holder for time spent in space, leaving Bykovsky’s endurance record well behind!

Fuel Cells for Survival


A diagram showing the fuel cells installed on Gemini 5. Despite their problems on this mission, NASA expects to use fuel cells to provide electrical power and water on future space flights.

Another fuel cell problem surfaced on day four of the mission, but this was relatively minor, which was fortunate as the fuel cells not only produce electrical power for the Gemini spacecraft, but also provide the water supply for the crew. Like a battery, a fuel cell uses a chemical reaction to create an electric current. The Gemini fuel cell uses liquid oxygen and liquid hydrogen to generate electricity, which creates water as a by-product. Cooper and Conrad reported that the water had a lot of gas bubbles in it (with a predictable intestinal result!) and that it also had a taste they didn’t like. However, it was drinkable when mixed with Tang powdered orange drink, so I think that this will become a staple on future missions (a good advertising opportunity there!).

A plentiful supply of water also means that NASA will be able to provide the astronauts with more rehydratable foods from now on, although the Gemini 5 crew apparently did not have much of an appetite during the mission, only consuming about 1000 calories a day, instead of the planned 2700 calories.


Thanks to fuel cell-produced water, future NASA missions will have more rehydratable foods available. This sample Gemini meal includes a beef sandwich, strawberry cereal cubes, peaches, and beef and gravy. Astronauts use the water gun to reconstitute the food and scissors to open the packages

More Problems to Endure

The fifth day of the mission saw a major problem develop when one set of OAMS thrusters began to malfunction. This meant that all experiments where the thrusters needed to be used were cancelled. One cancellation was a great disappointment for us here in Australia. The Visual Acuity Test was designed to gauge the acuity of an astronaut’s vision from space, by observing patterns laid out on the ground.

Two test sites were prepared for this Gemini 5 experiment: one at Laredo, Texas and the other on Woodleigh sheep station (ranch), located about 90 miles south of Carnarvon, Western Australia. Carnarvon is the site of NASA’s largest tracking station outside the United States, combining both a Manned Space Flight Network facility and a Space Tracking and Data Acquisition Network station. At Woodleigh, piles of white sea-shells were bulldozed into carefully chosen patterns to determine the smallest pattern the astronauts could discern through the window of their spacecraft.


The Visual Acuity Test patterns at Woodleigh station seen from the air. Though they were composed of very white shells from a nearby beach, I think they might have been difficult to spot from space even under ideal conditions.

However, when this experiment should have been performed on 26 August, Gemini 5 was again drifting along powered down, due to the fuel cell and OAMS problems and could not maintain a stable view of the ground. The astronauts could see the smoke markers identifying the Woodleigh site but not the experimental patterns themselves due to the spacecraft's attitude. Attempts to view the site on later orbits were, unfortunately, no more successful, although the crew could see the lights of Carnarvon and Perth on night-time orbits.

During this powered-down period, Cooper and Conrad became quite cold and experienced feelings of disorientation caused by stars drifting past the windows as their capsule slowly rotated. Eventually, Cooper put covers on the windows to shut out the sight. Not only did they have difficulty sleeping, the crew also had to contend with persistent dandruff, apparently due to the low cabin humidity. The dry, flaky skin they shed settled everywhere, making for an unpleasant cabin environment. Even the instrument panels became partially obscured by dandruff!


No wonder the Gemini 5 crew found it difficult to sleep, when they were crowded together in a space about the same size as the front seat of a VW Beetle! Sleeping in alternate shifts was was not successful, but even sleeping at the same time did not make for a restful "night".

Although the mission’s technical problems caused some experiments to be cancelled, many others were still successfully carried out, including medical and photographic experiments. Among the crew's space science pictures were the first photographs of the zodiacal light and the gegenschein taken from orbit. Photographs of the Earth taken from space are also expected to produce detailed images that will have scientific, military and intelligence value once the films taken in flight are processed. I'm really looking forward to seeing them.

100 Orbits

On 28 August, Gemini 5 became the first manned spacecraft to complete 100 orbits of the Earth. In recognition of the achievement, Mission Control in Houston relayed 15 minutes of Dixieland music to the two astronauts, making Capcom Jim McDivitt the first space disc jockey! Because of the cancellation of experiments during the mission, Conrad had previously said he wished he had brought a book to read, or some music to listen to, and both Cooper and Conrad had expressed a preference for Dixieland music. Later that day, the Capcom at Houston also read up to the crew a little poem that Conrad’s wife, Jane, had written.

From Space to Shining Sea

A few hours before Gemini 5 returned to Earth yesterday, Gordon Cooper made a very special long-distance call – to fellow Mercury astronaut Scott Carpenter, who is living and working aboard the US Navy’s Sealab II facility, 205 feet beneath the surface of the Pacific Ocean near La Jolla, California. This radio call was apparently made to test the effectiveness of an undersea electronics lab installed on Sealab II, but it was also a nice piece of publicity for NASA and the Navy.


Mercury astronaut turned aquanaut Scott Carpenter, inside Sealab II, talks to Gordon Cooper aboard Gemini 5. Don't ask me how I got this photo!

Eight Days Without Busting!

Finally, on 29 August, at 190 hours, 27 minutes, and 43 seconds into the mission, retrofire commenced and Gemini 5 was on its way home. To demonstrate the level of control provided by the Gemini spacecraft design, the astronauts controlled their re-entry, rotating the capsule to create drag and lift. Unfortunately, due to an error by a computer programmer, Gemini 5 splashed down in the Atlantic Ocean 80 miles short of its target landing site, but the crew were quickly located and retrieved. Gemini 5 ended just a few hours short of the planned eight days, but the epic mission had come to a successful conclusion and lived up to its motto – it was most definitely not a bust!


Safely home! The crew of Gemini 5 look tired, but elated, after what what Conrad has described as "“eight days in a garbage can”. Notice those "censored" mission patches, whose motto was right after all!




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