Mission Type: Lander, Orbiter
Launch Vehicle: 8K82K + Blok D (Proton-K no. 285-02)
Launch Site: NIIP-5 / launch site 81P
Spacecraft Mass: 5,033 kg at Launch
Spacecraft Instruments:
Orbiter: 1) imaging system; 2) infrared radiometer; 3) ultraviolet imaging spectrometer; 4) magnetometer; 5) photopolarimeter; 6) ion/electron detectors; and 7) optical spectrometer
Lander: 1) panoramic imaging system; 2) thermometer; 3) barometer; 4) mass spectrometer; 5) anemometer; 6) photometers; 7) nephelometer; 8) gamma-ray spectrometer; 9) radiation densitometer; and 10) accelerometers.
References:
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/

Solar System Log by Andrew Wilson, published 1987 by Jane's Publishing Co. Ltd.

Venera 10, like its sister craft Venera 9, fully accomplished its mission to soft-land on Venus and return data from the surface. The spacecraft followed an identical mission to that of its twin, arriving only a few days later after two trajectory corrections on 21 June and 18 October 1975.

The 660-kilogram lander separated from its parent on 23 October and entered the atmosphere two days later at 01:02 UT. During reentry, the lander survived gravity acceleration as high as 168 g and temperatures as high 12,000°C. It performed its complex landing procedures without fault and landed without incident at 02:17 UT approximately 2,200 kilometers from the Venera 9 landing site. Landing coordinates were 16° north latitude and 291° longitude.

Venera 10 transmitted for a record 65 minutes from the surface, although it was designed to last only 30 minutes. A photo of the Venera 10 landing site showed a smoother surface than that of its twin. Like Venera 9, Venera 10 was supposed to take a 360° panorama but covered only 180° of the surroundings because of a stuck lens cover.

Meanwhile, the Venera 10 orbiter entered a 1,400 x 114,000-kilometer orbit around Venus inclined at 29?30'. Soviet officials later revealed that the termination of data reception from both Veneras 9 and 10 was not caused by the adverse surface conditions but by the flying out of view of the orbiter relays for both spacecraft. Gamma-ray spectrometer and radiation densitometer data indicated that the surface layer was akin to basalt rather than granite as hinted by the information from Venera 8.