Venera 1, also known as Venera-1VA No.2 and occasionally in the West as Sputnik 8 was the first spacecraft to fly pastVenus, as part of the Soviet Union's Venera programme. Launched in February 1961, it flew past Venus on 19 May of the same year; however, radio contact with the probe was lost before the flyby, resulting in it returning no data.
Spacecraft
Venera 1 was a probe consisting of a cylindrical body in diameter topped by a dome, totalling in height. This was pressurized to with dry nitrogen, with internal fans to maintain even distribution of heat. Two solar panels extended from the cylinder, charging a bank of silver-zinc batteries. A 2-metre parabolic wire-mesh antenna was designed to send data from Venus to Earth on a frequency of 922.8 MHz. A 2.4-metre antenna boom was used to transmit short-wave signals during the near-Earth phase of the mission. Semidirectional quadrupole antennas mounted on the solar panels provided routine telemetry and telecommand contact with Earth during the mission, on a circularly-polarized decimetre radio band. The probe was equipped with scientific instruments including a flux-gate magnetometer attached to the antenna boom, two ion traps to measure solar wind, micrometeorite detectors, and Geiger counter tubes and a sodium iodidescintillator for measurement of cosmic radiation. An experiment attached to one solar panel measured temperatures of experimental coatings. Infrared and/or ultraviolet radiometers may have been included. The dome contained a KDU-414 engine used for mid-course corrections. Temperature control was achieved by motorized thermal shutters. During most of its flight, Venera 1 was spin stabilized. It was the first spacecraft designed to perform mid-course corrections, by entering a mode of 3-axis stabilization, fixing on the Sun and the star Canopus. Had it reached Venus, it would have entered another mode of 3-axis stabilization, fixing on the Sun and Earth, and using for the first time a parabolic antenna to relay data.
Launch
Venera 1 was the second of two attempts to launch a probe to Venus in February 1961, immediately following the launch of its sister shipVenera-1VA No.1, which failed to leave Earth orbit. Soviet experts launched Venera-1 using a Molniyacarrier rocket from the Baikonur Cosmodrome. The launch took place at 00:34:36 GMT on 12 February 1961. The spacecraft, along with the rocket's Blok-L upper stage, was initially placed into a 229 × 282 km low Earth orbit, before the upper stage fired to place "Venera 1" into a heliocentric orbit, directed towards Venus. The 11D33 engine was the world's first staged-combustion-cycle rocket engine, and also the first use of an ullage engine to allow a liquid-fuel rocket engine to start in space.
Failure
Three successful telemetry sessions were conducted, gathering solar-wind and cosmic-ray data near Earth, at the Earth's Magnetopause, and on February 19 at a distance of. After discovering the solar wind with Luna 2, Venera 1 provided the first verification that this plasma was uniformly present in deep space. Seven days later, the next scheduled telemetry session failed to occur. On May 19, 1961, Venera 1 passed within of Venus. With the help of the British radio telescope at Jodrell Bank, some weak signals from Venera 1 may have been detected in June. Soviet engineers believed that Venera 1 failed due to the overheating of a solar-direction sensor.
