DOS-2

{{short description|Failed Soviet space station (1972)}}

{{Infobox space station

| station = DOS-2

| insignia = Salyut_program_insignia.svg

| insignia_size = 160px

| insignia_caption =

| crew = 2

| launch = 29 July 1972
03:21 UTC

| launch_pad = LC-81/24, Baikonur Cosmodrome, USSR

| mass = 18,425 kg
(40,620 lb)

| length = 14 m

| width = 4.15 m

| volume = c.100 m³ (3,500 ft³)

| in_orbit = 0 days
(Launch failure)

| stats_ref = {{cite web|url=http://ston.jsc.nasa.gov/collections/TRS/_techrep/RP1357.pdf|title=Mir Hardware Heritage|author=David Portree|publisher=NASA|year=1995|url-status=dead|archiveurl=https://web.archive.org/web/20090907191412/http://ston.jsc.nasa.gov/collections/TRS/_techrep/RP1357.pdf|archivedate=2009-09-07}}

| configuration_image = RP1357 p64 Salyut 1.svg

| configuration_size =

| configuration_caption = Planned orbital configuration of DOS-2

|configuration_class=skin-invert-image}}

DOS-2 was a space station, launched as part of the Salyut programme, which was lost in a launch failure on 29 July 1972, when the failure of the second stage of its Proton-K launch vehicle prevented the station from achieving orbit.{{cite web|url=https://www.archives.gov/files/declassification/iscap/pdf/2018-070-doc3-nara-lbj-508.pdf|title=Central Intelligence Bulletin: USSR 29 Jul 72, 7|publisher=CIA|year=1972}}{{cite web|url=https://www.archives.gov/files/declassification/iscap/pdf/2018-075-doc1-508.pdf|title=Central Intelligence Bulletin: USSR 29 Jul 72, 8|publisher=CIA|year=1972}} It instead fell into the Pacific Ocean. The station, which would have been given the designation Salyut 2 had it reached orbit, was structurally identical to Salyut 1, as it had been assembled as a backup unit for that station.{{cite book|title=Salyut: The First Space Station|year=2008|publisher=Springer-Praxis|isbn=978-0-387-73585-6|author=Grujica S. Ivanovich}} Four teams of cosmonauts were formed to crew the station, of which two would have flown:

• Alexei Leonov and Valeri Kubasov
• Vasily Lazarev and Oleg Makarov
• Aleksei Gubarev and Georgi Grechko
• Pyotr Klimuk and Vitaly Sevastyanov

Whilst Salyut 1 had been attempted to be visited by two three-person crews (Soyuz 10 and Soyuz 11), following modifications to the Soyuz 7KT-OK spacecraft (resulting in the new model Soyuz 7K-T) following the deaths of the crew of Soyuz 11, the spacecraft could only carry two cosmonauts, thus DOS-2 would have had two crews of two. Following the loss of the station, the crews were transferred to the DOS-3 programme.