Sputnik - Half a Century Ago

(Update: 10/04/2007, below)

In two days, we will commemorate an extraordinary technological marker in our modern history, the launching of the first man-made satellite into space, Sputnik I, by the Soviet Union. It happened fifty years ago, during the long-planned International Geophysical Year, or IGY, an eighteen month long scientific endeavor highlighting eleven geophysical, or "earth" sciences. It was an achievement that at the time quite electrified the world, and initiated an international competition that became known as the Space Race.

A recently retrieved copy of the article that appeared the next day, October 5th, in the New York Times, gives a good indication of the surprise and concerns that the launch immediately raised. It included quotes, for example, from scientists assuring people that the satellite could not be used to drop atomic or hydrogen bombs from the sky! Viewed in the context of the Cold War, which had really begun a decade earlier with the Truman Doctrine responding to Soviet aggression in Europe, that launch was seen as a startling wake-up call within the United States, and a propaganda coup for the Soviets.

The Times article noted the immediate Soviet boasts:

It said in its announcement that people now could see how "the new socialist society" had turned the boldest dreams of mankind into reality.

So it was on October 4, 1957, that the Soviet Union launched its Sputnik I, or literally, "co-traveler-1" a small man-made satellite, into earth orbit. It was the first such man-made earth orbiting satellite ever. The Soviets wanted to be first, and had scaled back plans for a more sophisticated device, settling on a small satellite with no mission payload. It transmitted radio signals for 22 days, when it went silent on October 26, 1957. The small satellite, approximately 23 inches in diameter, plus antennas, stayed in orbit until it re-entered the earth's atmosphere on January 4, 1958, almost four months later. It was small enough that in passing over it could be viewed by ground observers only with the aide of field glasses.

Two months after the first launch, the Soviets successfully launched a second, and significantly larger earth orbiting satellite, Sputnik II, on November 3, 1957, one with a mission payload and a female dog named Laika on board. Because of mechanical problems associated with a block not separating properly, it was many years later publicly revealed that she likely did not survive more than a few hours because of over-heating. But they had put the first living animal in space, paving the way for manned space flights. Sputnik II was large enough that it could be seen with the naked eye. Newspaper accounts at the time record the excitement of observers checking for scheduled "pass overs," and then watching it as the bright yellow moving star passed overhead.

Sputnik I had not been the first time a man-made rocket had reached what we call space, which begins about 62 miles above the surface of the earth. That had taken place years before.

In 1944, a V2 rocket was launched from Peenemünde on a vertical test shot sub-orbital trajectory to an altitude of 176 km (109 miles), well beyond the 100 km (62 miles) altitude generally considered to be the border of space (see Kármán line).

And earlier in April of 1957, the United States Navy had launched a "satellite" payload to an altitude of 126 miles. But Sputnik I was the first object to reach first cosmic velocity, or the speed that is required for an object to achieve earth orbit from the earth -- approximately 17,500 miles per hour. It moved slightly faster than that, and over its entire lifetime traveled a total of about 60 million miles.

Meanwhile, the failure of the United States to be the "first" in space, set off a public debate here, and further highlighted embarrassing "mis-launches" of rockets in the Vanguard series. Most notable, for obvious reasons, was the attempted Vanguard launch on December 6, 1957, made in the wake of the Sputnik launches. It only made it about four feet in the air and then dropped back, crashed, toppled and exploded on the launch pad. It was viewed by the public right on TV, for everyone to see. The "payload" itself fell free and the slightly damaged satellite can still be seen at the National Air and Space Museum.

The United States quickly switched rockets, and finally successfully launched its first satellite, the Explorer I, aboard a Juno I rocket on January 31, 1958.

Radiation recordings from that Explorer I satellite were later confirmed to have detected an enormous radiation belt, charged particles in space held in place by the earth's gravitation, later named the Van Allen radiation belt.

The discovery of the Van Allen Belts by the Explorer satellites was considered to be one of the outstanding discoveries of the International Geophysical Year.

The satellite instrumentation for Explorer I had been designed and built by Dr. James Van Allen from the University of Iowa. Though the batteries went dead in a matter of months, Explorer I stayed in orbit for over 12 years.

One of the previously ill-fated Vanguard series of satellites was finally launched on March 17, 1958, with the TV-4 satellite, a remarkable technological achievement, one that continued to transmit data until years later in 1964. In fact, the satellite itself is still in orbit today, and is expected to last in orbit for a total of 240 years!

For the world back them on that early October day, fifty years ago, a remarkable change took place, and the space race was off and running. Very much on people's minds was the concern that the Soviet Union had somehow gained an insurmountable lead in the development of Inter-Continental Ballistic Missiles, or ICBMs. The Soviets took every opportunity to promote their "technological superiority" around the world. People even speculated about whether the "mysterious beeping" of the radio signals from Spitnik I was some form of secret code! President Eisenhower was queried repeatedly at his next press conference about the national security implications of the launch. And three years later in the Presidential election of 1960, an alleged "missile gap" was a hot issue.

But as we look back now, having clearly outpaced the Soviet technology, and outlived both the Cold War and the Soviet Union, what is clear is that the communications revolution that emerged from those first satellite launches, is what still completely dominates our world.

Ten years ago, the New York Times published an on-line presentation commemorating the Sputnik I launch, including many of the stories and a chronology from the time. It is well worth paging through today.


Update: 10/04/2007 pm -- The BBC also has an on-line version of their story from that day. The on-line version also has an interesting chronological feature, "Timeline: Space" also worth checking.