On
October 4, 1957 the space age began. The Soviet Union launched
"Sputnik", the very first man-made satellite, into earth's
orbit. Sputnik, only about 23 inches wide, weighed some 184 pounds.
It
was designed to orbit the Earth at about 18 thousand miles per hour
at an altitude of 560 miles.
Scientists
around the world could hear Sputnik transmitting electronic signaling
back to earth and speculated on the information contained in those
beeps.
Years
later, the people who launched Sputnik confessed the beeps were used
simply to help track the satellite. Sputnik's launch triggered the
so-called "space race" between the United States and the
Soviet Union.
That
race didn't let up until twelve years later, when the U.S.
successfully sent astronauts to the moon in 1969.
History
changed on October 4, 1957, when the Soviet Union successfully
launched Sputnik I. The world's first artificial satellite was about
the size of a beach ball (58 cm.or 22.8 inches in diameter), weighed
only 83.6 kg. or 183.9 pounds, and took about 98 minutes to orbit the
Earth on its elliptical path. That launch ushered in new political,
military, technological, and scientific developments. While the
Sputnik launch was a single event, it marked the start of the space
age and the U.S.-U.S.S.R space race.
The
story begins in 1952, when the International Council of Scientific
Unions decided to establish July 1, 1957, to December 31, 1958, as
the International
Geophysical Year (IGY) because the scientists knew that the
cycles of solar activity would be at a high point then. In October
1954, the council adopted a resolution calling for artificial
satellites to be launched during the IGY to map the Earth's surface.
In July 1955, the White House announced plans to launch an Earth-orbiting satellite for the IGY and solicited proposals from various Government research agencies to undertake development. In September 1955, the Naval Research Laboratory's Vanguard proposal was chosen to represent the U.S. during the IGY.
Sputnik itself provided scientists with valuable information, even though it was not equipped with sensors, by tracking and studying the satellite from Earth. The density of the upper atmosphere could be deduced from its drag on the orbit, and the propagation of its radio signals gave information about the ionosphere.
In July 1955, the White House announced plans to launch an Earth-orbiting satellite for the IGY and solicited proposals from various Government research agencies to undertake development. In September 1955, the Naval Research Laboratory's Vanguard proposal was chosen to represent the U.S. during the IGY.
The
Sputnik launch changed everything. As a technical achievement,
Sputnik caught the world's attention and the American public
off-guard. Its size was more impressive than Vanguard's intended
3.5-pound payload. In addition, the public feared that the Soviets'
ability to launch satellites also translated into the capability to
launch ballistic missiles that could carry nuclear weapons from
Europe to the U.S. Then the Soviets struck again; on November 3,
Sputnik II was launched, carrying a much heavier payload, including a
dog named Laika.
Immediately
after the Sputnik I launch in October, the U.S. Defense Department
responded to the political furor by approving funding for another
U.S. satellite project. As a simultaneous alternative to Vanguard,
Wernher von Braun and his Army Redstone Arsenal team began work on
the Explorer
project.
Sputnik itself provided scientists with valuable information, even though it was not equipped with sensors, by tracking and studying the satellite from Earth. The density of the upper atmosphere could be deduced from its drag on the orbit, and the propagation of its radio signals gave information about the ionosphere.
Sputnik
1
was launched during the
International
Geophysical Year
from Site
No.1/5, at the 5th Tyuratam
range, in Kazakh
SSR (now known as the Baikonur
Cosmodrome). The satellite travelled at about 29,000 kilometres
per hour (18,000 mph; 8,100 m/s), taking 96.2 minutes to
complete each orbit. It transmitted on 20.005 and 40.002 MHz,
which were monitored by amateur
radio operators throughout the world. The signals continued for
21 days until the transmitter batteries ran out on 26 October 1957.
Sputnik
1
burned up on 4 January 1958, as it fell from orbit upon reentering
Earth's
atmosphere, after travelling about 70 million km (43.5 million
miles) and spending three months in orbit.
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