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Science / Space Race

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

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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?

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Science / Space Race

[August 31, 1961] Look on the bright side (August space round-up)

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by Gideon Marcus

Did you ever eagerly wait for Christmas only to be disappointed by what you found under the tree (or, for my fellow Jews, under the menorah)?  That's what this month must feel like for fans of the American space program.  While the Soviets achieved a huge success in August with the multiple orbiting of Gherman Titov, the National Aeronautics and Space Administration had a lousy 31 days.

For one thing, our lunar efforts seem to be cursed.  Ranger 1, launched on August 22, was the first of the third generation of Moon probes.  The flight was a test mission, designed to range high above the Earth but not reach the Moon.  Like the earlier Pioneer missions, Ranger 1 was far from a success.  The second stage of its rocket, the much ballyhooed Agena, hiccoughed.  Instead of going into a high orbit where it could do all sorts of interesting sky science, the satellite ended up in a low orbit that grazed the top of the Earth's atmosphere.

Not only was the poor probe doomed to a short life as the relatively thick air dragged Ranger 1 down with each circling of the Earth, it couldn't get enough power, either.  Ranger was designed to bask for hours at a time in the Sun in the slow, high part of its planned orbit.  Instead, the hapless vehicle plunged into shadow every 45 minutes causing it to vent great gouts of nitrogen gas to orient itself toward the sunrise which came three quarters of an hour later.  Ranger quickly ran out of gas, its panels fell out of alignment to receive energy, and soon after, the ship's batteries gave up the ghost.  When Ranger reentered yesterday, it had been silent for three days.

No science was gathered from the probe.  About the only thing that can be said for Ranger 1 is that its systems worked properly despite the extremely adverse conditions.  Let's hope Ranger 2, scheduled for October, breaks the bad luck streak.

Meanwhile, Explorer 13, a craft of the S-55 class designed to measure all the dust and rocks whizzing about in orbit, went up on August 24.  Like Ranger, its orbit was lower than planned, and it fell blazing to Earth just four days later.  Not that the lifespan of the "beer can" satellite meant much – not a single impact was recorded on any of the probe's wide array of sensors.  Again, the NASA boys found a silver lining: now they know to equip the next S-55 with more sensitive detectors!

Even the Air Force has been having a rough time of it.  Their 28th Discoverer spy satellite failed to orbit on August 4.  Discoverer 29 went up yesterday; we'll see if the flyboys are able to recover their film capsule or not in a few days.

So, was there any good news this month?  Actually, yes!  Remember Explorer 12, which launched two weeks ago?  It has already returned so much data that scientists are overwhelmed.  Explorer will keep broadcasting, but ground stations are only going to listen periodically.  The data already suggests that there is a sharp decline in Earth's magnetic field 50,000 miles up in the direction of the Sun, as if the two celestial bodies are fighting each other to a standstill out in space.  Explorer 12 will stay up for a year, and the scientific harvest is bound to be a bumper crop. 

In fact, it's important to remember that there are still a bevy of probes still beep-beeping away, carrying out scientific missions: Tiros 3, Explorer 9, Explorer 11, Echo 1, even the venerable Vanguard 1.  We did lose one of the family recently, however.  Explorer 7 went off the air on August 24 after nearly two years in space. 

But that's nearly 100 in satellite years, right?

Next up…  the Galaxy!

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Science / Space Race

[August 17, 1961] Voyages of Discovery (Explorer 12)

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Every so often, a discovery comes along that shatters our conception of the universe.  Galileo turned his telescope to the heavens and discovered moons around Jupiter – suddenly, it was clear that Earth was not the center of everything.  Roentgen and Curie showed that matter was not entirely stable, leading to our modern understanding of physics (and the challenges that come with the harnessing of atomic energy).  Columbus sailed to find Asia; instead, he was the first to put the Americas on European maps.

Until 1958, space was believed to be a sterile place, a black void in which the planets and stars whirled.  Maybe there was an odd meteoroid or two, and far away, one might find a big cloud of gas, but otherwise space was synonymous with vacuum. 

Then Explorer 1, America's first space mission, went into orbit around the Earth.  Its particle detectors, designed to measure the free-floating electrons and cosmic rays whizzing around up there, quickly became saturated.  Girdling the planet were hellish streams of energy, particles ionized by the sun and trapped by the Earth's magnetic field. 

Overnight, our idea of space was revolutionized; a few scientists had speculated as to the existence of the "Van Allen Belts," but the idea was hardly mainstream.  More probes were sent up to determine the nature of these belts.  Pioneer 5 went beyond far into interplanetary space and sent back news of a solar atmosphere that extended far beyond the shiny yellow bits – a field of particles and rays that went beyond even Earth's orbit.  Other probes returned maps of the turbulent region where the sun's field met Earth's. 

Space was hardly empty – it was a new ocean filled with waves, eddies, and unknowns to be explored.

Yesterday, Explorer 12 zoomed into orbit, NASA's latest voyager to ply the charged sea of space.  While it practically grazes the Earth at its closest point in its orbit, at its furthest, Explorer 12 zooms out a full 50,000 miles – a fifth of the way to the Moon.  Twice every 31 hours, the satellite studies the Van Allen Belts as well as the region of cislunar space, that variable region in which the Earth and the Sun fight for magnetic dominance. 

Armed with a battery of instruments like that carried by its spiritual predecessor, Explorer 6, the new probe also has several strips of solar cells covered with varying levels of shielding.  These will help determine the extent to which the Van Allen Belts will affect ship's equipment as they travel through the deadly particles.  The data will be of particular use to Apollo astronauts on their way to the Moon.

If Explorer 1 was the satellite Columbus of the Van Allen Belts, and Explorer 6 was John Cabot, then Explorer 12 will be Amerigo Vespucci, fully determining the contours of a new ocean whose depths had been but briefly surveyed before. 

Shiver me timbers, laddie.  It's an exciting time to be a sailor!

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