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[May 30, 1965] Ticket to Ride (May space round-up)


by Gideon Marcus

It's been another exciting month in the realm of spaceflight.  We're between crewed missions, what with Voskhod 2 and Gemini 3 having flown in March and the next Gemini due in a few days.  Nevertheless, it has been a field day for robotic spacecraft, with a number of civilian and military packages booking passage aboard a plethora of satellites.  Take a look:

The Shape of Things that Came

Yuri Gagarin soared into history in April 1961, becoming the first human space traveler.  His face became known worldwide. His spacecraft, on the other hand, remained shrouded in mystery. For four years, the shape of the Vostok capsule remained a secret, with only a few dubious artists' conceptions offering any clues to its configuration.

That changed suddenly last month when the Soviets displayed the complete Vostok spacecraft at an exhibition in Moscow.  Now we know that the fanciful cylinders and bullet-shaped craft were completely off the mark — Vostok was spherical.

This is significant.  A sphere is a simple shape, mathematically, and it is not hard to weight a ball such that one end always points down.  In the Vostok, that point is where its heat shield was mounted.  A similar concept was employed with America's Mercury capsule, but the back end of the Mercury is only a small arc of a circle.  That's because American rockets were too weak to loft a full sphere.  Vostok is clearly a much heavier spacecraft than Mercury, and this suggests that the Soviet Vostok rocket was much more powerful than the Atlas and certainly the Redstone that lofted the first astronauts.

The unveiling of Vostok affords us a look into a completely different space program, too.  Earlier in the year, American intelligence determined that the Vostok had been turned into a spy satellite.  Instead of cosmonauts, the new Vostok carries a camera.  After a week snapping pictures in orbit, the capsule parachutes to Earth, and the film is developed.  It's an elegant repurposing, though it has to be more expensive than the American analog, Discoverer.

While the Soviets do not announce their spy missions, it's not too hard to figure out which of their Kosmos "science satellites" are probably spy Vostoks.  Their orbits, sweeping them over Western targets of interest, and their short lifespans on the order of a week give them away.  In just the last two months, it's likely that Kosmoses 64, 65, and 66 were all spy satellites.  In a few days, we'll know if Kosmos 67, launched on May 25, is also a space shutterbug.

Softly, softly

Another probe about which the Soviets are being less than forthcoming is Luna 5.  Launched on May 9, the ton-and-a-half spacecraft was headed for the Moon.  Reportedly, it conducted a mid-course maneuver on May 10, directing it toward the Sea of Clouds — which it hit at 10:10 PM, Moscow time.  Per TASS, "During the flight and the approach of the station to the moon a great deal of information was obtained which is necessary for the further elaboration of a system for soft landing on the moon’s surface."

That might lead one to the conclusion that Luna 5 was the Soviet version of Ranger, a TV probe designed to take pictures until it crashed.  However, Western observers using telescopes saw the plume of dust that one would expect accompanying an attempt at a soft landing.  That such a landing did not occur suggests that Luna 5 was supposed to be an equivalent of our Surveyor, set to launch next year, and that things did not go as planned.  The lunar race thus remains neck and neck.

Exploring, Communicating

The last month saw two more entries into the Explorer series: Explorer 27, launched April 29, is a windmill-shaped little satellite that will measure irregularities in the Earth's shape; a secondary mission is probing the ionosphere.

Meanwhile, Explorer 28 was launched on May 28, and is the latest in the Interplanetary Monitoring Probe series, along with Explorers 18 and 21.  All three craft have high, eccentric orbits that allow them to thoroughly map Earth's magnetic field, though Explorer 18 went kaput earlier this month.

As we saw with last month's flight of Intelsat 1, space-based communications are now a fact of everyday life.  The USSR has now gotten in on the act, following up the flight of Early Bird with their own first satellite called Molniya, launched April 22, 1965.  It has a high, 12-hour orbit, not quite geosynchronous, designed to service the high latitude residents of the Soviet Union during the daytime.  European nations have already requested use of the Molniyas; they feel that the "international" Intelsat corporation too strongly favors the United States.


Finally, the Air Force's second "Lincoln Experimental Satellite," launched May 6, has been a success.  This next-generation communications satellite tests new technologies that will allow it to service hundreds of users at a time.  Its predecessor, LES-1 launched February 11, failed to fire its onboard engine that would kick it from its initial low orbit.  LES-2 had no such problems, and its orbit takes it more than 9000 miles above the surface of the Earth.

Of course, being a military satellite (as opposed to Telstar, Relay, and Syncom), it is possible that we civilians won't see immediate benefits, but I suspect they will trickle down in good time.

Another step Moonward

May 25 marked the ninth successful launch of the Saturn rocket, possibly the biggest rocket on Earth.  At its tip were boilerplates of the Apollo Command and Service Modules.  But these mock spacecraft weren't the stars of the show: inside the cylindrical Service Module was a giant satellite, the second Pegasus.  Appropriately adorned with a pair of enormous wings, Pegasus will stay in orbit for years measuring how many micrometeoroids our astronauts are likely to encounter on their way to the Moon.

The reliability of the Saturn is truly remarkable.  Remember the early days of the Space Race?  Chances were 50/50 then that any given rocket, Atlas, Juno, or Vanguard, would blow up on the launch pad, tilt off course, or otherwise fail.  We're now in an age of maturing space travel.  If Gemini's Titan rocket continues to do as well as the Saturn, I do believe that, by the 1970s, everyday citizens like you and me will be able to get tickets to ride into space. 



This week's Journey Show is a special Space Race episode!  Don't miss it!




[Oct. 16, 1964] Three in One (The next leg of the Space Race)


by Gideon Marcus

A whole new ballgame

It's not often that news of the next stage in the Space Race is eclipsed by an even bigger story.  Yet that's exactly what happened this tumultuous week, a handful of days so crazy that we halted publication ("STOP THE PRESSES!") to keep up with events.

It all started with "Kosmos 47", launched just after midnight (San Diego time) on October 6.  While the Soviets were typically close-lipped about its purpose, from its orbital path, it was suspected that the 24 hour flight was actually an uncrewed test of a new type of Soviet spacecraft.

Sure enough, just six days later, Voskhod ("Sunrise") #1 took off.  On board were three cosmonauts: Commander Vladimir Mikahilovich Komarov, civilian scientist Konstantin Petrovich Feoktistov, and civilian physician Boris Borisovich Yegorov.

This is huge news — both the American Mercury and Soviet Vostok space programs ended more than a year ago.  Those spacecraft only fit one person.  Since then, the United States has been hard at work on both its three-person Apollo lunar craft and its intermediate two-seat Gemini ship.  Although Gemini has already flown once, the first crewed flight won't happen until early next year.

And here are the Soviets, already throwing up a three person spaceship!  Could they be closer to a Moon mission than we thought?

On their eighth orbit, Voskhod's cosmonauts passed over the United States and radioed, "From aboard the spaceship, Voskhod, we convey our best wishes to the industrious American people.  We wish the people of the United States peace and happiness."

Interestingly, a second radio exchange was heard afterwards, during orbit sixteen: the three cosmonauts requested permission to extend the mission beyond 24 hours.  The request was denied, and the flight ended just one day after it had begun.

Why is this strange?  Well, one of the stated goals of the mission was "Extended medio-biological investigations in conditions of a long flight."  And while 24 hours is a long flight by American standards (that of Gordo Cooper in Faith 7 was about a day and a half), the Soviets have been flying day-long and longer missions since Gherman Titov's flight in 1961.  Did something go wrong with the spaceship? 

It turns out the problem was on the ground.  Even as the three cosmonauts were making history in space, the Presidium was holding a vote of no confidence, citing Khruschev's age and health as reasons for his dismissal.  Leonid Brezhnev was elevated to Secretary of the Communist Party and Andrei Kosygin was named Premier.  When the space travelers landed, they were whisked to Moscow where they must have been quite surprised to meet the new leadership!

Still, regardless of who is wearing the crown behind the Iron Curtain, there is no question that Voskhod was a tremendous accomplishment.  The question now is: What will they follow it up with?

Beep Beep, says America

Though perhaps not as impressive to some, the United States maintains the lead in automated space science.  Just this month, we launched the two latest Explorer satellites, 21 and 22.  And while those numbers seem a lot lower than what the Soviet "Kosmos" series has gotten up to, we have to remember that Kosmos conceals a wide variety of satellites, most of which have never resulted in a scientific paper.  They have probably snapped a great many photos of Midwest missile bases, though.

In contrast, the Explorer program is just one of many devoted to returning scientific data from the heavens.  Explorer 21, launched on October 4 (seven years after Sputnik) is the second of its type.  Also known as Interplanetary Monitoring Platform (IMP) B, its job is the same as that of Explorer 18, launched in last year — to measure the magnetic fields, cosmic rays, solar wind, and charged particles far from the Earth.  This helps us understand the physics of the solar system, and it lets us map the electromagnetic "terrain" of the space between Earth and the Moon.  The IMPs are blazing a trail for Apollo, making sure it's safe for people out there.

Unfortunately, the third stage on IMP-B's Thor Delta launch booster fizzled, and instead of soaring 160,000 miles from the Earth, Explorer 21 barely gets to 60,000.  This is within the hellish Van Allen radiation belts, so even though Explorer 21's nine instruments are performing perfectly, the data being returned tells nothing about the universe beyond Earth's magnetic system.

However, Explorer 22, launched October 10, is doing just fine.  It's the last of NASA's first phase of ionospheric explorers, measuring the electron density in the upper atmosphere.  Before your eyes glaze, that just means it sees how electrically charged the air is in the layer that reflects radio waves.  Such experiments help us better understand how the Sun affects our broadcasts — and allows us to make plans for unusual space weather events. 

The satellite, also known as Beacon Satellite B ("A" failed to orbit on March 29) is also the first of NASA's geodetic satellites, measuring the shape of the Earth with tremendous precision.  What's neat about Explorer 22 is that the spacecraft is actually quite unsophisticated, just three radio beacons and a laser reflector.  More noteworthy are the 80 tracking stations run by 50 scientific groups in 32 countries.  These provide a worldwide web, collecting navigational data on an unprecedented scale.

And since it's a civilian probe, we'll probably even share the information with the Communists.  You tell me who's winning the Space Race…


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