Russia loses most of its missile-warning satellite group — media

Tundra satellites form the space-based component of Russia’s missile early-warning system. The minimum operational configuration of the constellation is four satellites.

Podvig based his assessment on orbital observation data. According to those data, only the satellite Kosmos-2552, launched in November 2021, remained operational by late 2025.

Even Kosmos-2552, however, appears to be experiencing technical issues. Around November 2025, the satellite was expected to perform an orbital correction maneuver, which did not take place. Podvig cautioned that it is still too early to conclude that the satellite has ceased functioning entirely.

In addition to Kosmos-2552, Russia launched Kosmos-2541 in September 2019 and Kosmos-2563 in November 2022. Both satellites later failed — the former after an orbital adjustment in March, and the latter following an adjustment in July.

Russian state propaganda agency TASS previously wrote, citing a source in the defense industry, that the minimum operational strength of the Tundra satellite group is four spacecraft. At the time, the source claimed that the deployment of the fourth satellite had brought the system to its required baseline capacity.

“The Unified Space System Kupol has been brought to its minimum operational configuration and makes it possible to track any launches of ballistic or space-launch missiles from U.S. territory,” the source said then.

Tundra-class satellites began launching in 2015 and were intended to replace the aging Oko-1 missile-launch detection system. The last Oko-1 satellites were launched in 2007–2008, exceeded their service life, and had fully ceased operation by the mid-2010s.