Venera 1 was the first spacecraft to fly by Venus. The probe consisted of a cylindrical body topped by a dome, totaling 2 meters in height. Two solar panels extended radially from the cylinder. A large (over 2 meter diameter) high-gain net antenna was used to receive signals from the ground. This antenna was attached to the cylinder. A long antenna arm was used to transmit signals to Earth. The probe was equipped with scientific instruments including a magnetometer attached to the end of a 2 meter boom, ion traps, micrometeorite detectors, and cosmic radiation counters. The dome contained a pressurized sphere which carried a Soviet pennant and was designed to float on the putative Venus oceans after the intended Venus impact. Venera 1 had no on-board propulsion systems. Temperature control was achieved with thermal shutters.
Venera 1 was launched along with an Earth orbiting launch platform (Tyazheliy Sputnik 5 (61-003C)) with a SL-6/A-2-e launcher. From a 229 × 282 km orbit, the Venera 1 automatic interplanetary station was launched from the platform towards Venus with the fourth stage Zond rocket. On February 19, 7 days after launch at a distance of about two million km from Earth, contact with the spacecraft was lost. On May 19 and 20, 1961, Venera 1 passed within 100,000 km of Venus and entered a heliocentric orbit.
