Venera 10 transmitted for a record 65 minutes from the surface, more than twice as long as it was designed to last. The Venera 10 orbiter returned information from Venus until June 1976.
Venera 10, like its sister craft Venera 9, fully accomplished its mission to soft-land on Venus and to return data from the surface.
The spacecraft followed an identical mission to its twin, arriving only a few days later after two trajectory corrections June 21, 1975, and Oct. 18, 1975. The 3,440-pound (1,560-kilogram) lander separated from its parent Oct. 23, 1975, and entered the atmosphere two days later at 01:02 UT.
During re-entry, the lander survived loads as high as 168 g’s and temperatures as high 21,632 degrees Fahrenheit (12,000 degrees Celsius). It performed its complex landing procedures without fault (see Venera 9 for details) and landed without incident at 05:17:06 UT approximately about 1,370 miles (2,200 kilometers) from the Venera 9 landing site. (Times were only announced for reception of landing signal on Earth). Landing coordinates were a 93-mile (150-kilometer) radius of 15.42 degrees north latitude and 291.51 degrees east 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. The small image size was part of the original plan, and was determined by the slow telemetry rates and an estimated 30-minute lifetime. Like Venera 9, the Venera 10 lander was supposed to take a 360-degree panorama but covered only 180-degrees of the surroundings because of a stuck lens cover.
Soviet officials later revealed that termination of data reception from both Venera 9 and 10 landers was not due to the adverse surface conditions, but because the orbiter relays for both spacecraft flew out of view.
Gamma-ray spectrometer and radiation densitometer (shaped a bit like a paint-roller deployed on the surface) data indicated that the surface layer was akin to basalt rather than granite as hinted by the information from Venera 8. The Venera 10 orbiter meanwhile entered a 1,000 x 70,200-mile (1,620 × 113,000-kilometer) orbit around Venus inclined at 29 degrees 30 minutes, transmitting data until at least June 1976.
Unlike the Venera 9 orbiter, photographs taken by the Venera 10 orbiter were never released and it remains unclear whether it actually carried a camera.
Siddiqi, Asif A. Beyond Earth: A Chronicle of Deep Space Exploration, 1958-2016. NASA History Program Office, 2018.