Tag Archives: solrad

[November 22, 1965] Keep on Exploring (Explorer-29 and 30 and Venera-2 and 3)


by Kaye Dee

November has been a busy month in space exploration with two new missions in NASA’s ongoing series of Explorer scientific satellites, and two spacecraft bound for Venus, launched by the Soviet Union. Let's get stuck right in and see why 1965 continues to be an amazing year for the space race.

GEOS is Go!

NASA’s Explorer series keeps on producing fascinating new scientific missions that help us discover as much about the Earth as they do about space. November’s first Explorer satellite, designated Explorer 29, also goes by the name of Geodetic Earth Orbiting Satellite (GEOS)-1 or GEOS-A. It is the first successful active spacecraft in the United States’ National Geodetic Satellite Program, and more are expected to follow.


NASA illustration of GEOS-1/Explorer-29 in orbit

Geodesy is the science of accurately measuring and understanding Earth's geometric shape, its orientation in space and the shape and characteristics of its gravitational field. You could say that passive satellite geodesy began with Vanguard-1, back in 1958, when scientists used the perturbations in its orbit to determine that the Earth is actually slightly pear-shaped, not quite that round ball we see in science fiction movies (though you'd have to have really sharp eyes to notice the difference!)

Satellite geodesy has come a long way in seven years and GOES-1 is carrying a suite of instruments that are designed to operate simultaneously, so that the data from each can be combined to give a highly accurate location for a point on the surface of the Earth. These instruments include four optical beacons, laser reflectors, Doppler beacons, and a range and range rate transponder. GEOS-1 also carries a SECOR transponder, the same type as used by satellites in the US Army’s satellite geodesy program, so that it can also contribute to that program’s research.


This US Army SECOR satellite bears an interesting resemblance to the Naval Research Laboratory's SOLRAD-8, as well as sharing a transponder type with GEOS-1

The objective is to use the data from all of Explorer-29’s instruments to precisely locate a series of observation points (or geodetic control stations) in a three dimensional “Earth centre-of-mass” coordinate system within 10 m of accuracy. These precision locations will help to improve the accuracy of cartography, surveying, and satellite navigation using the TRANSIT satellites.

GEOS-1’s instruments will also help in defining the structure of the earth's irregular gravitational field and refining the locations and magnitudes of the large gravity anomalies that have so far been detected. The various instrument systems will be compared with each other to determine which is the most accurate and reliable.

Explorer-29/GEOS-1 was launched from Cape Canaveral on 6 November (US time), on the first flight of the new Delta E launcher. Powered by solar cells, GEOS-1 uses gravity-gradient stabilisation, a relatively new technique that was first successfully tested on satellite 1963-22A, launched in June 1963. GEOS-1’s range and range rate transponder is tracked by NASA’s STADAN (Space Tracking and Data Acquisition Network) stations, including Carnarvon in Western Australia and the newly-operational station (just last month) at Orroral Valley, near Australia’s capital, Canberra.


NASA's new STADAN tracking station near Canberra tracks scientific satellites including the Explorer series – whatever alternate names they are known by

Satellite for a Quiet Sun

Explorer-29 was followed just two weeks later by Explorer-30, which also goes by the names of SOLRAD-8 and Solar Explorer-A (SE-A). The SOLRAD (short for Solar Radiation) program began in 1960, with the aim of providing continuous coverage of the wavelengths of solar radiation that can't be observed from Earth's surface. SOLRAD is a project of the Naval Research Laboratory and grew out of its earlier Vanguard program. Most of the earlier SOLRAD satellites have been launched piggy-back with other satellites (which, rumour has it, were of a classified nature), but SOLRAD-8 is the first to be launched as part of NASA’s Explorer program.

SOLRAD-8 is part of International Quiet Sun Year program, which is studying the upper atmosphere and the space environment during the Solar minimum, the least energetic time in the Sun's 11 year activity cycle. The data gathered during this period can then be compared with information obtained during the International Geophysical Year, when the Sun was at its most active.


The Naval Research Laboratory's SOLRAD-8 will help us to better understand the differences in the space environment between periods of maximum and minimum solar activity

Launched on November 19 by a Scout X-4 rocket from NASA’s Wallops Island facility, SOLRAD-8 is composed of two 24-inch aluminium hemispheres, with an equatorial ‘belt’ carrying 14 X-ray and Ultra-violet photometers. The satellite weighs 125 pounds and is powered by six solar panels. SOLRAD-8 is the first satellite to use a new type of miniature gas thruster, firing ammonia, to stabilise itself with its spin axis perpendicular to the Sun. It transmits data back to Earth in real time, using a FM/AM telemetry system that is recorded at NASA’s STADAN network stations.

Will we Lift the Veil of Venus This Time?

Venus has proved to be a difficult planet to explore. Only one space probe so far, NASA’s Mariner-2 in 1962, arrived safely at the planet and returned data which indicated that Venus was molten hot, shattering all those tales of a ‘jungle Venus’ or a planet of island dotted oceans, like ERB’s Amtor. But this month, the Soviet Union is making another attempt to visit our mysterious ‘sister’ planet and pierce its veil of clouds.


Official pictures released by the Soviet Union showing Venera-2 (top) and Venera-3 (below). The slight difference between the design of the two space probes is a hint that they might have different missions when they arrive at Venus

Not one, but two spacecraft are on their way to Venus: Venera-2, launched 12 November, was quickly – and much to the West’s surprise – followed only four days later by Venera-3. Both spacecraft were launched from the USSR’s Baikonur Cosmodrome and seem to be safely on their way. It is assumed that the Soviet Union has launched a pair of space probes so that, as with NASA’s Mariner-3 and 4, if one fails the other might still succeed in sending back data to Earth. However, TASS has said that the two probes have slightly different equipment, so some of my colleagues at the WRE have suggested that perhaps the Russians are trying something bolder with this twin mission: maybe one probe will perform a flyby past Venus and the other will either try to go into orbit – or maybe even impact on the planet’s surface. That would be a really exciting achievement: I can’t wait to learn what exciting information these spacecraft will send back to earth in a few months’ time!






[February 5, 1964] That was the Month that Was (January's Space Roundup)


by Gideon Marcus

Another Lunar Black Eye

NASA's Project Ranger, which is basically a projectile aimed at the moon, has logged failure after failure since it started back in 1961.  The first ones in the series, Rangers 1 and 2, were just Earth-orbiting satellites designed to test the engineering and return scientific data.  Both of their missions were busts due to fault Agena second stages on their Atlas-Agena boosters.

Rangers 3 to 5 were bona-fide moon missions with giant pimples on their noses to do a bit of lunar geology (or selenology).  None of them completed their missions: Ranger 3 missed its target and was pointed the wrong way to boot, Ranger 4 hit the moon but was brain-dead from orbit onward, and Ranger 5 both missed and stopped working long before it got near the moon.

With five cracked eggs' experience to draw from, NASA tried again in January 30, 1964, with the first of the TV-armed Rangers, #6.  Aside from an odd voltage spike early on, Ranger 6 seemed to be working fine.  The spacecraft made a textbook-perfect flight all the way to its target, Mare Tranquillitas, impacting on schedule. 

But its TV camera never turned on.

I've been told that the fellow who announced the flight in real-time to the press has resigned from this duty, unable to go through such a harrowing experience again.  Who can blame him?  This is the sixth Ranger and the tenth failed (counting Pioneer Atlas Able) moon mission in a row.  On the other hand, and this is probably weak comfort at best, Ranger 6 did perform perfectly all the way until the end.  I'm sure Our American Cousin was a fine play, too.

There are three more third edition Rangers left to launch.  Let's hope at least one of them will be successful.  Right now, this program is making Project Vanguard look like an unalloyed success.

Stillborn Quintuplets

Speaking of Vanguard, on January 24, 1964, the Air Force launched another of its multi-satellite missions, attempting to orbit an unprecedented five spacecraft at once.  "Composite 1" comprised LOFTI 2, which was to study the ionosphere, Secor and Surcal, which would have helped the Army and Navy (respectively) calibrate their tracking radars, and Injun 2, a radiation satellite made by the University of Iowa (the same folks who discovered the Van Allen Belts.

Composite 1 also included SOLRAD (Solar Radiation) 4, and this is the Vanguard tie-in.  You see, the spottily successful Vanguard, which was America's first space project, was originally designed to study the sun's output of X-rays and ultraviolet light.  Unfortunately, the last of the Vanguards, number 3, was swamped with radiation from the Van Allen Belts, and its sun-pointed experiments were made useless.  End of story, right?

Well, SOLRAD 1, launched in 1960, was essentially Vanguard 4.  It was made by the same folks (the Naval Research Laboratory), used the same design, and carried the same experiments as Vanguard 3.  The only difference was purpose: the Navy wanted to know if there was a relation between solar flares and radio fade-outs (turns out yes). 

SOLRAD 2 was a dud thanks to a bad rocket, but SOLRAD 3 and Injun 1 returned good data.  The failure of SOLRAD 4 gives the program a .500 average — still pretty good to my mind.  I understand the Air Force will be trying again in a few months.

Five for five

How about some good news for a change?  For the fifth time in three years, the world's largest rocket took to the skies above Florida, January 29, 1964.  The Saturn I rocket, a precursor to the Saturn V behemoth that will take humans to Moon before this decade is out, has completed its run of test flights with a 100% success rate. 

I want that to sink in.  As far as I know, no rocket program has ever been 100% successful.  One would think that a booster as big as the Saturn should be more accident-prone than any other.  And yet, the trim cylindrical stack lifted off from Cape Kennedy, with both stages fueled for the first time, and placed its entire top half into orbit.  This gave Americans another first: world's largest satellite, weighing nearly ten tons!

The timing could not be better.  Apollo's future has been threatened a bit lately, with many in Congress seeking to reduce NASA's funding.  Some question whether there is even value in winning the race to the moon.  The outstanding success of the Saturn I will hopefully be a shot in the program's arm — and maybe for the related Project Ranger.

Now that testing of the rocket is complete, the Saturn I will go on to operational missions, flying full-scale examples of the Apollo spacecraft.  This will be the closest this first Saturn ever gets to the moon, however.  Huge as it is, it is not strong enough to launch Apollo to Earth's nearest neighbor.  It's not even strong enough to loft a fully-fueled Apollo!  But it's bigger brother, the Saturn IB, will be.  Expect its first flights in 1966 or so.

Can you hear me?

Last year, COMSAT corporation started selling publicly traded shares.  COMSAT was President Kennedy's compromise between a public and private satellite communications entity.  COMSAT has not yet developed any comsats, but that hasn't other entities are continuing to build experimental satellites toward the day when COMSAT birds begin to fly.

Relay 2

On January 21, 1964, the RCA-built Relay 2 joined its sister Relay 1, Ma-Bell-made Telstar 2, and the fixed-in-the-sky Syncom 2 in orbit.  With four active comsats in orbit (the kind that can retransmit broadcasts), we'll likely soon see transmissions bounce all over the globe.  The most exciting programming on the schedule?  This summer's Olympic games, live from Tokyo, Japan!

Echo 2

Just four days after the launch of Relay 2, NASA shot up Echo 2, a balloon-type passive reflector satellite — essentially a big mirror in space for bouncing signals.  It's larger than Echo 1, which is still in orbit, and should be visible from the ground when it zooms overhead.  I'm not sure why NASA bothered with this satellite given the sophistication of the active-repeater comsats.  I suspect there won't be many more.

Gavarit pa Ruskii?

Meanwhile, our Communist friends have not been entirely idle.  In addition to their increasing constellation of little Kosmos satellites, which may or may not be civilian in nature (probably not), the Soviets have created the twin "Elektron" orbiting laboratories.  The first two were launched on January 30 into separate orbits, their mission to explore the Van Allen Belts from both below and above!

It's the first time the Soviets have launched multiple satellites on a single rocket (we've been doing it since SOLRAD 1) and the first time since Sputnik 3 that a Russian mission has been verifiably civilian in nature. 

It's about time!

Space for Two

I'll wrap things up with a couple of pieces of news on the Gemini two-seat spacecraft, sort of a bridge between Projects Mercury and Apollo.  Firstly, it looks like the first uncrewed flight will happen as early as March, testing both the capsule and the Titan II rocket.  If this goes well, the first crewed flights may blast off as early as the end of this year.

Fingers crossed!




[March 24, 1963] Bumper Crop (A bounty of exciting space results)


by Gideon Marcus

February and March have been virtually barren of space shots, and if Gordo Cooper's Mercury flight gets postponed into May, April will be more of the same.  It's a terrible week to be a reporter on the space beat, right?

Wrong!

I've said it before and I'll say it again.  Rocket launches may make for good television, what with the fire, the smoke, and the stately ascent of an overgrown pencil into orbit…but the real excitement lies in the scientific results.  And this month has seen a tremendous harvest, expanding our knowledge of the heavens to new (pardon the pun) heights.  Enjoy this suite of stories, and tell me if I'm not right…

How hot is it?

Mariner 2 went silent more than two months ago, but scientists are still poring over the literal reams of data returned since its rendezvous with Venus.  The first interplanetary mission was a tremendous success, revealing a great deal about the Planet of Love, whose secrets were heretofore protected by distance and a shroud of clouds. 

Here's the biggie: Preliminary reports suggested that the surface temperature of "Earth's Twin" is more than 400 degrees Fahrenheit.  It turns out that was a conservative estimate.  In fact, the rocky, dry landscape of Venus swelters at 800 degrees — possibly even hotter than the day side of sun-baked first planet, Mercury.  It's because the planet's dense carbon dioxide atmosphere acts like a heat blanket.  There's no respite on the night side of the hot world either; the thick air spreads the temperatures out evenly.

Thus, virtually every story written about Venus has been rendered obsolete.  Will Mariner 3 destroy our conception of Mars, too?

Just checking the lights

On February 25, the Department of Defense turned little Solrad 1 back on after 22 months of being off-line.  The probe had been launched in conjunction with a navigation satellite, Transit, back in June 1960.  For weeks, it had provided our first measurements of the sun's X-ray output (energy in that wavelength being blocked by the Earth's atmosphere and, thus, undetectable from the ground).  DoD has given no explanation for why the probe has been reactivated, or why it was turned off in the first place.  Maybe there's a classified payload involved?

Radio News from the Great White Spacecraft

Last September, the Canadians launched their first satellite — the "top-sounder," Alouette, whose mission was to measure the radio-reflective regions of our atmosphere from above.  The results are in, and to any HAM or communications buff, its huge news.

It turns out that the boundaries of the ionosphere are rougher at higher latitudes than at lower latitudes.  Moreover, Alouette has determined that the Van Allen Belts, great girdles of radiation around our planet, dip closer to the Earth at higher latitudes.  This heats up the ionosphere and causes the roughness-causing instability. — the more active the electrons, the poorer the radio reflection.  Now we finally know why radio communication is less reliable way up north.  The next step will be learning how to compensate for this phenomenon so that communication, both civil and military, can be made more reliable.

Sun Stroke Warning

After a year in orbit, NASA's Orbiting Solar Observatory is still going strong, with 11 of 13 experiments still functioning.  The satellite has probably returned more scientifically useful data than all of the ground-based solar observatories to date (certainly in the UV and X Ray spectra, which is blocked by the atmosphere).

Moreover, OSO 1 has returned a startling result.  It turns out that solar flares, giant bursts of energy that affect the Earth's magnetic field, causing radio storms and aurorae, are preceded by little microflares.  The sequence and pattern of these precursors may be predictable, in which case, OSO will give excellent advance warning of these distruptive events.

Tax money at work, indeed!

Galaxy, Galaxy, Burning Bright

In the late 1950s, astronomers began discovering some of the brightest objects in the universe.  It wasn't their visible twinkle that impressed so much as their tremendous radio outbursts.  What could these mysterious "quasi-stellar sources" be?

Now we have a pretty good guess, thanks to a recent scientific paper.  Cal Tech observers using the Mt. Wilson and Mt. Palomar observatories turned their gaze to object 3C 273, a thirtheenth magnitude object in the constellation of Virgo.  It turns out that 3C 273's spectrum exhibits a tremendous "red shift," that is to say, all of the light coming from it has wavelengths stretched beyond what one would expect.  This is similar to the decrease in pitch of a railroad whistle as the engine zooms away from a listener.

The only way an object could have such a redshift is if it were of galactic proportions and receding from us at nearly 50,000 km/sec.  This would place it almost 200,000,000 light years away, making it one of the most distant (and therefore, oldest) objects ever identified.

At some point, astronomer Hubble's contention that the universe is expanding is likely to be confirmed.  These quasi-stellar objects ("quasars"?) therefore represent signposts from a very young, very tiny universe.  What exciting times we live in!

Five years of Beep, Beep

St. Patricks Day, 1958 — Vanguard 1 was the fourth satellite in orbit, but it was the first civilian satellite, and it is the oldest one to remain up there.  In fact, it is the only one of the 24 probes launched in the 1950s that still works.

What has a grapefruit-sized metal ball equipped with a radio beacon done for us?  Well, plenty, actually.  Because it has been tracked in orbit so long, not only have we learned quite a bit about the shape of the Earth (the variations in Vanguard's orbit are due to varying gravities on the Earth, the measurement of which is called "geodetics"), but the satellite's slow decay also tells us a lot about the density of the atmosphere several hundred miles up.

So, while Sputnik and Explorer might have had the first laughs, Vanguard looks likely to have the last for a good long time.

Telstar's little brother does us proud

RCA's Relay 1, launched in December, is America's second commercial communications satellite.  It ran into trouble immediately upon launch, its batteries producing too little current to operate its transmitter.  Turns out it was a faulty regulator on one of the transponders; the bright engineers switched to the back-up (this is why you carry a spare!), and Relay was broadcasting programs across the Atlantic by January.  660 orbits into its mission and 500 beamed programs later, NASA announces that Relay has completed all tests. 

Nevertheless, why abandon a perfectly good orbital TV station?  Relay will continue to be used to transmit shows transcontinentally, especially now that Telstar has finally gone silent (February 21).  There is even talk that Relay could broadcast the Tokyo Olympics in 1964, if it lasts that long!

In a sea of Blue, a drop of Red

On March 12, 3-12 at the Spring Recognition Dinner of Miracle Mile Association, in Los Angeles, Cal Tech President, Lee DuBridge, noted that the United States has put 118 probes into space, while the Russians have only lofted 34 (that we know of).  He also pointed out that virtually no scientific papers have resulted from the Soviets' "science satellites." 

As if in reply, on March 21 the Soviets finally, after 89 days without a space shot, launched Kosmos 13.  (To be fair, it's been kind of quiet on the American side, too).  The probe was described as designed to "continue outer space research."  No description of payload nor weight specifications were given.  Its orbit is one that allows it to cover much of the world.  While it may be that some of the Kosmos series are truly scientific probes, you can bet that, like America's Discoverer program, the Kosmos label is a blind to cover the Russians' use of spy satellites.  Oh well.  Turnabout is fair play, right?

[Next up, don't miss Mark Yon's spotlight of this month's New Worlds!  And if I saw you at Wondercon, do drop me a line…]




[February 1, 1962] Silver Lining (January Space Race round-up!)


by Gideon Marcus

January has been a frustrating month in the Space Race.  We are no closer to matching the Soviets in the manned competition, much less beating them, and our unmanned shots have been a disappointment, too.  That said, it's not all bad news in January's round-up: stick to it through the end, and you'll see cause for cheer!

Quintuplets fail to deliver

The Air Force has been playing around with combined launches for a while now.  After all, if you're going to spend millions of dollars to throw a booster away, you might as well get multiple bangs for your buck.  Sadly, the latest attempt, a Thor Ablestar launch on January 24 dubbed "Composite 1," failed when the top stage tumbled in orbit and failed to separate from its payloads.

What we lost: SolRad 4, for measuring solar X-rays (only visible above the curtain of the atmosphere); Lofti 2, which would have examined the effects of Earth's ionosphere on Very Low Frequency radio transmissions; Surcal, a strictly military probe designed to calibrate the navy's communications net in orbit; the wholly civilian Injun 2, which would help map the Van Allen belts (see below); and Secor, a big balloon that would have helped the Army with their ranging equipment.

Copies of these probes will end up at some point, either launched together on a big rocket or separately on little ones.

Moon Miss-ion

It's been a bad run of luck for NASA's latest moon program, Project Ranger.  After the failure of the first two Ranger missions, designed to test the probe's engineering and return sky science, there were high hopes for the lunar flight, launched January 26. 

Things went badly from the beginning.  Ranger 3 was pushed into a bad trajectory by a faulty guidance system.  Not only did it rush past the moon, failing both to hit the target or end up in orbit, but it was pointed the wrong way the entire length of the journey.  No useful data or pictures were obtained.  That nifty seismometer that makes up Ranger's Rudolph nose went completely unused. 

Ranger 4, a carbon copy of #3, should launch in the next few months.  Hopefully, they'll have the kinks worked out by then.  This is one of those clear places where the Communists are ahead in the space race, having pioneered both lunar orbit and the moon's surface several years ago.

A rain check for Mercury

The third time turned out also not to be the charm for Major John Glenn.  His orbital Mercury mission has now been postponed three times.  It's a good thing the Marine is so good-natured; I know I'd be frustrated.

The first delay happened on January 22 when there was a failure in the spacecraft's oxygen system.  Definitely something I'd like working on a five hour flight!  On the 27th, cloud cover prevented the launch, and just today, there was a problem with the temperamental Atlas booster.  The next opportunity to launch won't come until February 13.

So much is riding on this flight.  The Soviets have already launched two of theirs into orbit while we flutter futilely on the ground.  Newspapers and talking heads are already opining that we'll have a Red-staffed space station and a Red-dominated moon before long if we don't hurry to catch up. 

Explorer 12: Reaping the harvest

Here's the good news: I've said before that the most exciting thing about a satellite is not its fiery launch but the heap of data it returns.  That's where the taxpayer gets one's money's worth and where the scientist sees the payoff.  Explorer 12 was the latest in the series of probes (starting with America's first, Explorer 1) sent into orbit to probe the hellish fields of charged particles that circle the Earth.  The spacecraft is still up there, though it went silent in December.  However, in its four months of life, it learned a great deal about the furthest reaches of our planet's influence.

For one, Explorer 12 found that the outer of the two "Van Allen" belts around our planet is made mostly of protons rather than electrons (though there are still plenty of the latter — enough to make hanging around a dangerous proposition for astronauts).  Those protons, particularly the less energetic ones, have been linked to solar magnetic storms, which result in spectacular auroras on Earth.

Perhaps even more interesting is that the probe found the edge of the Earth's magnetosphere.  "What's that?" you ask.  Well, our planet is a giant magnet, probably the result of a dense iron core that spins deep inside the Earth.  These magnetic lines of force extend far beyond the Earth's crust and 70,000 kilometers into space where they trap the wind of high energy particles from our sun.  This keeps them from scouring away our atmosphere. 

Where our magnetic field meets the field carried on the solar wind, called the magnetopause, there is an area of turbulence and disorganized magnetism. It is now believed that the sun's wind smashes against the Earth's field, creating a bow shock – the kind you'd see when a blunt body is smacked by a supersonic gas.  Moreover, the Outer Van Belt "breathes" inward and outward, responding to waves in the solar wind.

And speaking of magnetic fields, NASA scientists just released findings from the intentionally short-lived Explorer 10 found a magnetic "shadow" behind the Earth.  Specifically, the solar wind seems to hit our planet's magnetosphere and deflect around the Earth, but the magnetic field acts as kind of an umbrella, shielding a large portion of near-Earth space. 

The general contours of Earth's magnetic environment have thus been mapped.  Neat stuff, eh?

[June 30, 1961] Reaping the Harvest (June 1961 space science results)

June was a busy month for space travel buffs, especially those who live in the Free World.  Here's an omnibus edition covering all of the missions I caught wind of in the papers or the magazines:

Little lost probe

The Goddess of Love gets to keep her secrets…for now.  The first probe aimed at another planet, the Soviet "Venera," flew past Venus on May 19.  Unfortunately, the spacecraft developed laryngitis soon after launch and even the Big Ear at Jodrell Bank, England, was unable to clearly hear its signal.

The next favorable launch opportunity (which depends on the relative positions of Earth and Venus) will occur next summer.  Expect both American and Soviet probes to launch then.

X Marks the Spot

Just as planes use fixed radio beacons to determine their position, soon submarines (and people!) will be able to calculate where they are by listening to the doppler whines of whizzing satellites.  Transit 4A, launched by the Navy, joined the still-functioning Transit 2 on June 29 (#3 conked out March 30, and #1's been off the air since last July). 

This Transit has an all-new power source.  Instead of batteries or solar panels, it gets its juice from little nuclear reactors.  These aren't aren't like the big fission plants you see being established all over the country.  Rather, they are powered by the heat of radioactive decay.  These energy packs are small and much simpler than solar panels.  Expect to see them used quite a bit on military satellites.

The Navy gets extra points for making their rocket do triple-duty: Also boosted into orbit were Injun 1 and Solrad 3.  The first is another University of Iowa particle experiment from the folks who discovered the Van Allen Belt; the latter a solar x-ray observatory.

Along a dusty trail

Contrary to popular belief, outer space is not empty.  There are energetic particles, clouds of dust, and little chunks of high-speed matter called micrometeorites.  All of them pose hazards to orbital travel.  Moreover, they offer clues as to the make-up and workings of the solar system. 

Prior satellites have tried to measure just how much dirt swirls around in orbit, but the results have been vague.  For instance, Explorer 8 ran into high-speed clouds of micrometeorites zooming near the Earth late last year corresponding with the annual Leonids meteor shower.  Vanguard 3 encountered the same cloud in '59, around the same time.  But neither could tell you precisely how many rocks they ran into; nor could previous probes.

NASA's new "S(atellite)-55" is the first probe dedicated to the investigation of micrometeorites.  It carries five different experiments — a grid of wires to detect when rocks caused short circuits, a battery of gas cells that would depressurize when impacted, acoustic sounding boards…the whole megillah.  It is one of those missions whose purpose is completely clear, accessible to the layman, unarguably useful.

Sadly, the first S-55, launched today from Wallops island, failed to achieve orbit when the third stage of its Scout rocket failed to ignite. 

It's a shame, but not a particularly noteworthy one.  The Scout is a brand new rocket.  We can expect teething troubles.  Every failure is instructive, and I'll put good money on the next S-55, scheduled for launch in August.

Worth the Wait

Speaking of Explorer 8, Aviation Week and Space Technology just reported the latest findings from that satellite.  Now, you may be wondering how a probe that went off the air last December could still generate scientific results.  You have to understand that a satellite starts returning data almost immediately, but analysis can take years. 

I'd argue that the papers that get published after a mission are far more exciting than the fiery blast of a rocket.  Your mileage may vary.  In any event, here's what the eighth Explorer has taught us thus far (and NASA says it'll be another six months until we process all the information it's sent!):

1) The ionized clouds that surround a metal satellite as it zooms through orbit effectively double the electrical size of the vehicle.  This makes satellites bigger radar targets (and presumably increases drag).

2) We now know what causes radio blackouts: it is sunspot influence on the lower ionosphere. Solar storms create turbulence that can cut reception.

3) The most common charged element in the ionosphere is oxygen.

4) The temperature of the electrons Explorer ran into was about the same as uncharged ionospheric gas – a whopping 1800 degrees Kelvin.

This may all seem like pretty arcane information, but it tells us not just about conditions above the Earth, but the fundamental behavior of magnetic fields and charged particles on a large scale.  Orbiting a satellite is like renting the biggest laboratory in the universe, creating the opportunity to dramatically expand our knowledge of science.

Air Force discovers Pacific Ocean

The 25th Discoverer satellite, a two-part vehicle designed to return a 300 pound capsule from orbit, was successfully launched June 16.  Its payload was fished from the Pacific Ocean two days later, the recovery plane having failed to catch it in mid-descent.  I recently got to see one of those odd-tailed Fairchild C-119 aircraft that fly those recovery missions; they're bizarre little planes, for sure. 

As for the contents of the space capsules, it's generally assumed that they carry snapshots of the Soviet Union taken from orbit.  This time around, however, the flyboys included some interesting experiments: three geiger tubes, some micrometeroid detectors, and a myriad of rare and common metals (presumably to see the effects of radiation upon them). 

You may be wondering what happened to Discoverers 23 and 24 (the last Discoverer on which I've reported was numbered 22).  The former, launched on April 8, never dropped its capsule; the latter failed to reach orbit on June 8.  Unlike NASA, the Air Force gives numbers to its failed missions.

Next Mercury shots planned

Virgil I. "Gus" Grissom is set to be the next Mercury astronaut in late July.  His flight will be a duplicate of Alan Shepard's 15 minute jaunt last month.  If all goes well, astronaut John Glenn will fly a similar mission in September.

I don't think the Atlas is going to be ready in time this year for an orbital shot.  That means there will be several tense months during which the Soviets could upstage us with yet another spectacle. 

[June 30, 1960] On a roll! (Space Race Wrap-up)

Something very exciting happened this week: Spaceflight became routine.

Remember just a couple of years ago?  The press was full of flopniks, grapefruit-sized spacecraft, and about a launch every other month.  Every mission was an adventure, and space was the great unknown.

All that has changed.  Not only are we launching more, and more advanced scientific satellites, but we are launching satellite systems.  Only two months ago, the Navy launched the first of the Transit satellites.  These satellites allow a ground-based observer to determine one's location to a fair degree of accuracy.  But since there's no guarantee any one satellite will be overhead at a given time, you need a constellation of Transits.

Number two was launched last week on June 22.  The age of reliable space utilization has dawned.

The news gets even more exciting: The launch of Transit also marked the first piggyback mission.  A little scientific probe called Solrad hitched a ride along with the navigation satellite.  How's that for efficiency?

Solrad is actually quite a neat little device.  For a while, scientists have been trying to study the Sun in the X-Ray spectrum, but the devices carried by Explorer 7 and Vanguard 3 were swamped by the charged particles swirling around the Earth in the so-called Van Allen Belts; thus no useful data was obtained. 

Navy scientists solved this problem in two ways.  First, they put the probe in a lower orbit, avoiding the worst of the Belt radiation.  Second, they employed the simple expedient of placing a large magnet on the front of the detector.  This swept out the unwanted electrons leaving the satellite's sensors clear for observing the Sun.

Solrad doesn't take pictures, mind you.  It just measures the raw value of solar X-ray flux.  But already, the probe has contributed significantly to science–in a rather unexpected field. 

Long distance communications on Earth are largely conducted via radio.  Sometimes, signals will fade out for no (hitherto) discernible reason.  Solrad has found out why–the level of solar X-ray emissions directly affects the radio-reflective properties of the Earth's ionosphere, that upper atmospheric layer of charged particles that causes radio waves to bounce across the planet rather than simply flying off into space.  Thanks to Solrad, and probes like it, I can imagine a time in the near future when we'll not only have a daily weather report, but also a radio reception report.

Speaking of communications, the Air Force reports that, in about a month, it will be launching a real communications satellite (unlike SCORE which just broadcast a prerecorded message).

It's not all good news on the Space Front, however.  I present to you the Galactic Journey obituaries for the month of June:

The Air Force has lost yet another Discoverer satellite: Discoverer 12 never made it to orbit; its booster suffered a second stage failure and crashed into the Atlantic.  Better luck next time.

Transit 1 went offline the day before Transit 2 launched.  I don't know if that was intentional or coincidental.

TIROS 1, the world's first weather satellite, threw in the towel on June 18, 1960.  It is my understanding that the probe did not perform as reliably as had been hoped, but we should see a TIROS 2 in the near future.

Pioneer 5, the first deep space probe, appears to have passed beyond the range of radio reception.  My sources inform me that the last telemetry was received on June 27.  STL engineers will continue to try to resume contact, however.

Services will be held next Sunday at 12:00 PM.  In attendance will be the currently functioning satellites: Vanguard 1, Explorer 7, Transit 2, and Solrad 1.