Mission Type: Impact
Launch Vehicle: Modified SS-6 (Sapwood) with 2nd Generation Upper Stage + Escape Stage, 8K78 (no. L1-6)
Launch Site: Tyuratam (Baikonur Cosmodrome), U.S.S.R, NIIP-5 / launch site 1
Spacecraft Mass: 643.5 kg
Spacecraft Instruments: 1) three-component magnetometer; 2) variometer and 3) charged-particle traps
Maximum Data Rate: 770 MHz at 1.6 bit/sec
Deep Space Chronicle: A Chronology of Deep Space and Planetary Probes 1958-2000, Monographs in Aerospace History No. 24, by Asif A. Siddiqi
National Space Science Data Center, http://nssdc.gsfc.nasa.gov/
This was the second of two Venus impact probes that the Soviets launched in 1961. This time, the probe successfully exited Earth orbit and headed toward Venus. Despite some initial problems with the solar orientation system, the spacecraft responded properly during a communications session on 17 February 1961 at a distance of 1.9 million kilometers.
Unfortunately, controllers were unable to regain contact during a subsequent communications attempt on 22 February. A later investigation indicated that the spacecraft had lost its "permanent" solar orientation due to a faulty optical sensor that malfunctioned because of excess heat after the spacecraft's thermal control system failed.
The inert spacecraft eventually passed by Venus on 19 and 20 May 1961 at a distance of about 100,000 kilometers and entered heliocentric orbit.