Goals: This spacecraft was designed to orbit the Moon and study the lunar environment.
Accomplishments: Luna 10 was the first spacecraft to orbit the Moon. It achieved 460 orbits over 56 days before its batteries were depleted and it stopped transmitting. During that time, tracking data showed that the spacecraft's orbit was being distorted by strong irregularities in the Moon's gravity field, providing the first evidence that the Moon's internal composition wasn't uniform. It also provided data on the Moon's weak-to-nonexistent magnetic field, radiation belts, and atmosphere; its surface composition; and the region's cosmic radiation and micrometeoroid density.
31 Mar 1966: Launch
3 Apr 1966: Lunar Orbit Insertion
Mission Type: Orbiter
Launch Vehicle: Modified SS-6 (Sapwood) with 2nd-generation upper stage + escape stage; 8K78M (no. N103-42)
Launch Site: Tyuratam (Baikonur Cosmodrome), USSR; NIIP-5 / launch site 31
Spacecraft Mass: 1,582 kg at launch; 245 kg in lunar orbit
2) gamma-ray spectrometer
3) five gas-discharge counters
4) two ion traps and a charged-particle trap
5) piezoelectric micrometer detector
6) infrared detector
7) low-energy x-ray photon counters
Spacecraft Dimensions: 1.5 m tall, 75 cm diameter at its base
Spacecraft Power: Battery
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.
Erik M. Conway, Historian, Jet Propulsion Laboratory
After a midcourse correction on 1 April, Luna 10, the second of two hastily prepared Soviet Ye-6S probes (that is, the backup), successfully entered lunar orbit two days later at 18:44 UT, thus becoming the first human-made object to go into orbit the Moon. A 245-kilogram instrument compartment separated from the main bus, which was in a 350 x 1,000-kilometer orbit inclined at 71.9° to the lunar equator.
The spacecraft carried a set of solid-state oscillators that had been programmed to reproduce the notes of the Internationale so that it could be broadcast live to the 23rd Communist Party Congress. During a rehearsal on the night of 3 April, the playback went well, but the following morning, controllers discovered a missing note and played the previous night's tape to the assembled gathering at the Congress, claiming it was a live broadcast from the Moon.
Luna 10 conducted extensive research in lunar orbit, gathering important data on the weakness of the Moon's magnetic field, its radiation belts, and the nature of lunar rocks (which were found to be comparable to terrestrial basalt rocks), cosmic radiation, and micrometeoroid density. During that time, tracking data showed that the spacecraft's orbit was being distorted by strong irregularities in the Moon's gravity field, providing the first evidence that the Moon's internal composition wasn't uniform. Last contact was on 30 May 1966.