Luna 24 was an unmanned space mission of the Soviet Union's Luna program. The last of the Luna series of spacecraft, the mission of the Luna 24 probe was the third Soviet mission to retrieve lunar soil samples from the Earth's moon (the first two sample return missions were Luna 16 and Luna 20). The spacecraft orbital dry mass was 4,800 kg (11,000 lb).
The probe landed in the area known as Mare Crisium (Sea of Crisis). The mission returned 170.1 grams of lunar samples to the Earth on 22 August 1976.
Luna 24 was the third attempt to recover a sample from the unexplored Mare Crisium, the location of a large lunar mascon (after Luna 23 and a launch failure in October 1975). After a trajectory correction on 11 August 1976, Luna 24 entered lunar orbit three days later. Initial orbital parameters were 115 kilometres at 120° inclination. After further changes to its orbit, Luna 24 set down safely on the lunar surface at 06:36 UT on 18 August 1976 at 12°45' north latitude and 62°12' east longitude, not far from where Luna 23 had landed.
Under command from ground control, the lander deployed its sample arm and pushed its drilling head about 2 metres into the nearby soil. The sample was safely stowed in the small return capsule, and after nearly a day on the Moon, Luna 24 lifted off successfully at 05:25 UT on 19 August 1976. After an uneventful return trip, Luna 24's capsule entered Earth's atmosphere and parachuted safely to land at 17:55 UT on 22 August 1976, about 200 kilometres southeast of Surgut in western Siberia. Study of the recovered 170.1 grams of soil indicated a laminated type structure, as if laid down in successive deposits. The Soviet Union swapped a gram of the mission sample for a lunar sample from NASA in December 1976.
Luna 24 was the last lunar spacecraft to be launched by the Soviet Union. As of 2012, it is also the last spacecraft from any country to have made a soft landing on the Moon.
Launch Vehicle: Proton (four stage version)
Launching Technique: Low orbit around Earth, translunar trajectory, then lunar orbit followed by landing;
Mass: 1,900 kilogrammes on lunar surface;
Length: 2.3 metres;
Maximum Diameter: 3.3 metres (including landing legs).
Boring 2.25 meters into the Moon, it obtained a 170.1 gram core sample 1.6 meters in length. The drilling apparatus packed the sample into a 8mm diameter plastic tube, which was wound into a helical container. At the Vernadsky Institute, the core was initially transfered to a flat spiral container to be x-rayed, then transfered to a series of trays. Luna-24 did not carry cycloramic cameras. Photos of the returned sample from Moscow Institute of Geochemestry and Analytic Chemistry n.a. Vernadsky are shown below: