Sputnik was the first man-made object that was successfully launched to orbit the Earth. It was a mission of the Soviet Union's Sputnik program. Under this program, the Soviet Union had launched a series of robotic spacecraft missions.
Sputnik is a Russian word which means 'traveling companion', or 'satellite'. It was launched on October 4, 1957. This ambitious mission was pursued by the Soviet Union to mark the International Geophysical Year. The launch program took place at 5 Tyuratam range in Kazakh (now known as Baikonur Cosmodrome). The satellite got off the ground at a speed of 29000 kilometers per hour. It was set up on the elliptical orbit of the Earth at a very low altitude. It completed one full rotation around the Earth on its oval-shaped path in one hour and 38 minutes.
In terms of technology, Sputnik was not a satellite of very high standards. It was like a large-sized basketball with a diameter of 58 cm, and a weight of just 83.6 kilograms. It was fitted with two radio transmitters, which were capable of sending signals to the Earth. It could be seen in the night sky all through its stay in its orbit.
The launch of this satellite marked the beginning of the Space Age, an era of space exploration, through advanced technology. It established the possibility of the use of artificial satellites to explore the upper layers of the Earth's atmosphere. It could identify the density of the atmospheric layers by measuring its own orbital changes.
It gave valuable data related to radio-signal distribution in the ionosphere. For the first time, meteoroids could be detected with the help of Sputnik. When any meteoroid got across the outer covering of the satellite, it was detected by means of temperature data, which was sent to the Earth. It also sent radio signals in the range of 20.005 and 40.002 MHz which were observed by several amateur radio operators all over the world.
Unfortunately, Sputnik was capable of sending signals for just 22 days, as after that, its batteries ran out. It traveled almost 60 million kilometers in its orbit, during a period of 3 months. It got burned up on January 4, 1958, falling from its orbit, when attempting to re-enter the Earth's atmosphere.
Sputnik signified a major breakthrough in scientific and technological advancements of the USSR, of that time. The success of this satellite triggered off a 'space race' between the two cold-warring nations, the United States and the USSR. With this event, the United States experienced a sudden sense of threat . They felt that if the Soviets could place a satellite in orbit, it meant they were equally well equipped to build rockets that could deliver nuclear warheads. In an attempt to surmount the scientific developments made by the Soviets, the United States founded various new scientific and military programs. It was around this time that the famous NASA (National Aeronautics and Space Administration) was established in the U.S.
Thus, it can be said that the triumph of the USSR in launching the first-ever artificial satellite, led to several military developments, and political repercussions around the world.