Tag Archives: transit 1

[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. 

[Sep. 19, 1959] Anchors Aweigh! (The Navy's Transit and Vanguard launches)

A bit of a stop press on the Space Race as I wade through this months Astounding, which I unwisely saved for last.  You should never eat dessert first…

Have you ever noticed how a train’s whistle seems to rise in pitch as the locomotive approaches and then the pitch lowers as the train departs?  This is caused by the compression of sound waves as they whistle heads toward your ears followed by a decompression as it heads away.  It’s called the Doppler Effect (after the 19th century Austrian scientist, Christian Doppler).

This concept will be used by satellites to provide accurate navigation aids for American military craft and, someday, civilians as well.  The idea is that the satellites, called Transit, will broadcast at a fixed frequency.  A receiver on the ground can tell from the quality of the Doppler frequency shifts, knowing the satellite’s orbit, where it is to within a small degree of error.  Very simple in concept.

Sadly, Transit 1 failed to orbit the day-before-yesterday when its Thor Able booster malfunctioned after liftoff.  On the other hand, the Navy (the service that developed the satellite) did get some useful data from the sub-orbital flight, I’m told.

Speaking of the Navy, the final flight of the Navy/civilian Vanguard program ended in success yesterday with the orbiting of Vanguard 3.  It is another x-ray, magnetosphere, and micrometeoroid detecting probe along the lines of the Explorers.  Its long-lasting orbit and conical shape will also allow the satellite to be used to determine the density of the upper atmosphere for decades to come.

I’ll publish more on the scientific findings of this probe as I hear them.  We are beyond the days where just getting the things up is the whole story.

And with that, the Vanguard program comes to an end with three successful flights out of 11.  This may sound like a poor record, particularly given the rather vicious coverage given the program by both domestic and foreign media (remember “Flopnik”?)

But Vanguard has enabled the reaping of a tremendous harvest.  As a booster, it was remarkably efficient and cheap.  The reliable second and third stages have been adopted as supplemental stages on other rockets, and it looks like the first stage will be turned into NASA’s new Vega second-stage system.  Thanks to Vanguard, there will be American property in space for the next several hundred years. 

Most importantly, Vanguard paved the way for a truly civilian space program.  Though it was derived from a Navy proposal, and spin-off technology from the program is being used by the military, the idea of a purely scientific and non-military space endeavor is a powerful and important one.  Our new space agency, NASA, owes much to it.

P.S. Galactic Journey is now a proud member of a constellation of interesting columns.  While you're waiting for me to publish my next article, why not give one of them a read!

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