Cosmos 2521

Launch data:

Description:

• No details of the payload that has been put into orbit have emerged – although it has been widely speculated that the satellite may be the first in a new generation of military geodesy satellites.

Mission details:

• On Jun 23, 2017 Russia launched a Defense Ministry satellite codenamed Cosmos-2519 into a 650 km polar orbit. It may be carrying a geodetic payload and a space surveillance (space debris monitoring) payload.
• Russia reported that the satellite-inspector completed a series of proximity operations experiments and returned to the Cosmos-2519 host satellite on Oct 26, 2017 in a 650 x 667 km orbit. Shortly afterwards a new object (2017-037E, 42986) was cataloged in a 554 x 664 km orbit; its nature is unknown.
• The Cosmos-2521 inspector satellite made a major orbit change on Apr 30, 2018 lowering its orbit from 644 x 660 km to only 350 x 369 km. Since then it has been undergoing natural orbit decay.
• On Aug 23, 2017 at about 0640 UTC a subsatellite, Cosmos-2521, separated from Cosmos-2519 at a relative speed of about 0.5 m/s. The subsatellite was described by Russia at that time as a ′satellite-inspector′. Cosmos-2521 and 2519 carried out a series of exercises involving orbital changes and mutual flybys.