The beginning of the space age
On October 4, 1957, the USSR launched the world's first artificial Earth satellite. The first Soviet satellite made it possible to measure the upper atmosphere density for the first time, to obtain data on the propagation of radio signals in the ionosphere, to work out the issues of launching into orbit, thermal regime, etc. The satellite was an aluminum sphere with a diameter of 58 cm and weight of 83.6 kg with four pin antennas 2.4-2.9 m long.
The initial parameters of the orbit were: perigee height 228 km, apogee height 947 km, inclination 65.1 g.
On November 3, the Soviet Union announced the launch of the second Soviet satellite into orbit, with the Laika dog and a telemetry system in a separate cabin to record its weightlessness, as well as scientific instruments for the study of solar radiation and cosmic rays.
On December 6, 1957, an attempt was made to launch the Avangard-1 satellite in the United States using a launch vehicle developed by the Naval Research Laboratory.
On January 31, 1958, the Explorer-1 satellite was put into orbit with an American response to the launch of Soviet satellites.
However, his payload was attached to the fourth, final stage of the Juno 1 launch vehicle. The satellite, together with the rocket in orbit, had a length of 205 cm and a mass of 14 kg. It was equipped with sensors of external and internal temperatures, sensors of erosion and impacts to determine the flow of micrometeorites and Geiger-Mueller counter to register penetrating cosmic rays.
An important scientific result of the satellite flight was the discovery of radiation belts surrounding the Earth. The Geiger-Mueller counter stopped counting when the satellite was at apogee at an altitude of 2530 km and its perigee height was 360 km.
On February 5, 1958 in the USA the second attempt to launch the satellite "Avangard-1" was made, but it also ended in an accident, as well as the first attempt. Finally, on March 17, the satellite was put into orbit. In the period from December 1957 to September 1959, eleven attempts were made to put into orbit "Avangard-1" only three of them were successful. Both satellites contributed a lot to space science and technology (solar panels, new data on upper atmosphere density, accurate mapping of islands in the Pacific, etc.) On August 17, 1958 in the USA the first attempt was made to send a probe with scientific equipment from Cape Canaveral in the vicinity of the Moon. It turned out to be unsuccessful. The rocket rose and flew only 16 km. The first stage of the rocket exploded at 77 from the flight. On October 11, 1958, the second attempt to launch the lunar probe "Pioneer-1" was unsuccessful. Subsequent launches were also unsuccessful, only March 3, 1959 "Pioneer-4", weighing 6.1 kg partially fulfilled its task: flew past the moon at a distance of 60,000 km (instead of the planned 24,000 km).
As well as with the launch of the Earth's satellite, the priority in the launch of the first probe belongs to the USSR, on January 2, 1959 was launched the first object created by human hands, which was placed on the trajectory, passing quite close to the Moon, in the orbit of the Sun's satellite. Thus, for the first time Luna-1 reached the second space velocity. "Luna-1 had a mass of 361.3 kg and flew past the Moon at a distance of 5500 km. At a distance of 113,000 km from Earth, a cloud of sodium vapor was released from the rocket stage docked to the Moon-1, which formed an artificial comet. Solar radiation caused a bright glow of sodium vapor and optical systems on Earth photographed the cloud against the constellation of Aquarius.
"Moon-2" launched on September 12, 1959 made the world's first flight to another celestial body. In the 390.2-kilogram sphere the devices were placed, which showed that the Moon has no magnetic field and radiation belt. Automatic interplanetary station (AMS) "Luna-3" was launched on October 4, 1959. The main purpose of the launch was to orbit the Moon and photograph its reverse side, invisible from the Earth. Photography was carried out on October 7 for 40 minutes from a height of 6200 km above the Moon.