The Special Committee for the International Polar Year (later designated the International Geophysical Year), was established. References: 483 .
Rocket test, 86 kg payload. Insufficient fin-cuff protection caused aerodynamic instability. Launched at 0840 local time. Reached 169 km.
Spacecraft was very similar to Venera 4 / 1V (V-67) although the descent module was of a stronger design. When the atmosphere of Venus was approached, a capsule weighing 405 kg and containing scientific instruments was jettisoned from the main spacecraft. During descent towards the surface of Venus, a parachute opened to slow the rate of descent. For 53 minutes, while the capsule was suspended from the parachute, data from the Venusian atmosphere were returned. The spacecraft also carried a medallion bearing the coat of arms of the U.S.S.R. and a bas-relief of V.I. Lenin to the night side of Venus.
First Rokot flight from Plesetsk, using a launch pad originally used for Kosmos rockets. The two-stage modified UR-100NUTTKh ICBM, delivered a Briz-KM upper stage to a suborbital trajectory. The first Briz burn was to an approximately 200 x 550 km transfer orbit; the second burn circularized at apogee. It placed two 660 kg dummy satellites in orbits similar to the parking orbit was used for the defunct Iridium program. The Briz-KM stage then made a third burn to lower its perigee to a 178 x 556 km x 86.4 deg disposal orbit.