Salyut 2 (OPS-1) (Russian: Салют-2 meaning Salute 2) was a Sovietspace station which was launched in 1973 as part of the Salyut programme. It was the first Almaz military space station to fly. Within two weeks of launch the station had lost attitude control and depressurised, leaving it unusable. It decayed from orbit by 28 May 1973, without any crews having visited it.
Salyut 2 was an Almaz military space station.  It was designated part of the Salyut programme in order to conceal the existence of the two separate space station programmes.
Salyut 2 was 14.55 metres (47.7 ft) with a diameter of 4.15 metres (13.6 ft), and had an internal habitable volume of 90 cubic metres (3,200 cu ft). At launch it had a mass of 18,950 kilograms (41,800 lb). A single aft-mounted docking port was intended for use by Soyuz spacecraft carrying cosmonauts to work aboard the station. Two solar arrays mounted at the aft end of the station near the docking port provided power to the station, generating a total of 3,120 watts of electricity. The station was equipped with 32 attitude control thrusters, as well as two RD-0225 engines, each capable of generating 3.9 kilonewtons (880 lbf) of thrust, for orbital manoeuvres.
Three days after the launch of Salyut 2, the Proton's spent third stage exploded. Thirteen days into its mission, Salyut 2 began to depressurise, and its attitude control system malfunctioned. An inquiry into the failure initially determined that a fuel line had burst, burning a hole in the station. It was later discovered that a piece of debris from the third stage had collided with the station, causing the damage.
Several pieces of debris separated from the space station at around the time of its failure, including both solar panels, which removed its ability to generate power. Three pieces of debris from the station were catalogued, and had decayed from orbit by 13 May. The remainder of the station reentered the atmosphere on May 28, 1973 over the Pacific Ocean.
^ abc"Salyut 2". United States National Space Data Center. 8 October 2010. Retrieved 4 January 2010.
^ abPortree, David S. F. (March 1995). "Mir Hardware Heritage". NASA. Retrieved 4 January 2011. "Salyut 2, the first Almaz station, reached orbit on April 3, 1973. Soon after, Salyut 2 lost stability and began tumbling. In 1992, Mikhail Lisun, backup cosmonaut for the Soyuz 24 flight to Almaz station Salyut 5, attributed the loss of Salyut 2 to an electrical fire, followed by depressurization. Salyut 2 broke up on April 14, and all trackable pieces reentered by May 28, 1973. This was a huge discovery