Kosmos 521

Kosmos 521
Mission type	ASAT target
COSPAR ID	1972-074A
SATCAT no.	06206
Mission duration	52 years, 4 days (in orbit)
Spacecraft properties
Spacecraft type	DS-P1-M
Manufacturer	Yuzhnoye
Launch mass	650 kilograms (1,430 lb)
Start of mission
Launch date	29 September 1972, 20:18:59 UTC
Rocket	Kosmos-3M
Launch site	Plesetsk 132/2
Orbital parameters
Reference system	Geocentric
Regime	Low Earth
Perigee altitude	987 kilometres (613 mi)
Apogee altitude	992 kilometres (616 mi)
Inclination	65.8 degrees
Period	104.9 minutes

Kosmos 521 (‹See Tfd›Russian: Космос 521 meaning Cosmos 521), also known as DS-P1-M No.4 is a satellite which was intended for use as a target for tests of anti-satellite weapons. It was launched by the Soviet Union in 1972 as part of the Dnepropetrovsk Sputnik programme,^[1] and was to have been used as a target for an IS-A interceptor, as part of the Istrebitel Sputnikov programme. A malfunction aboard the satellite rendered it useless, and the interceptor was not launched.^[2]

It was launched aboard a Kosmos-3M carrier rocket,^[3] from Site 132/2 at the Plesetsk Cosmodrome. The launch occurred at 20:18:59 UTC on 29 September 1972.^[4]

Kosmos 521 was placed into a low Earth orbit with a perigee of 987 kilometres (613 mi), an apogee of 992 kilometres (616 mi), 65.8 degrees of inclination, and an orbital period of 104.9 minutes.^[1] No attempt to intercept the satellite was made after its onboard telemetry system malfunctioned. As of 2009, it is still in orbit.^[2]^[5] Western analysts did not identify Kosmos 521 as being associated with the Soviet ASAT programme until records were declassified.

Kosmos 521 was the last of the five original DS-P1-M satellites to be launched,^[1] of which all but the first were successfully reached orbit. Despite its successful launch, the satellite malfunctioned shortly after reaching orbit, and was unusable. Subsequent launches used a modified version of the DS-P1-M, known as Lira.^[6]

References

^ ^a ^b ^c Wade, Mark. "DS-P1-I". Encyclopedia Astronautica. Archived from the original on 5 January 2009. Retrieved 29 May 2009.
^ ^a ^b Wade, Mark. "IS-A". Encyclopedia Astronautica. Archived from the original on 22 January 2012. Retrieved 29 May 2009.
^ McDowell, Jonathan. "Launch Log". Jonathan's Space Page. Retrieved 29 May 2009.
^ Wade, Mark. "Kosmos 3". Encyclopedia Astronautica. Archived from the original on 6 September 2008. Retrieved 29 May 2009.
^ McDowell, Jonathan. "Satellite Catalog". Jonathan's Space Page. Retrieved 29 May 2009.
^ Wade, Mark. "DS". Encyclopedia Astronautica. Archived from the original on 31 March 2009. Retrieved 29 May 2009.