Venera 1

Venera 1 was consisting of a cylindrical body 1.05 metres in diameter topped by a dome, totalling 2.035 metres in height. This was pressurized to 1.2 standard atmospheres with dry nitrogen, with internal fans to maintain even distribution of heat.[citation needed] 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 iodide scintillator 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. 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 1,900,000 km. 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 100,000 km 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.