A Russian satellite in space that United States officials believe is linked to a nuclear space weapons program appears to be malfunctioning, according to U.S. analysts.
The Cosmos 2553 satellite, launched by Russia weeks before invading Ukraine in 2022, has had various bouts of what appears to be erratic spinning during the past year, according to Reuters. The news agency cited data from two U.S. firms that reported the satellite has been spinning out of control, suggesting the spacecraft is no longer operational.
In November 2024, U.S.-based firm LeoLabs detected what appeared to be errant movements with the Cosmos 2553 using Doppler radar measurements from its global network of ground stations, according to Reuters. A second U.S. company, Slingshot Aerospace, detected similar movements in May 2024 using its global telescope network.
“Slingshot noted that the object’s brightness became variable, indicating a potential tumble,” a company spokesperson told Reuters, noting that the movement has since stopped.
Tracking conducted by United Kingdom-based company Spaceflux showed Cosmos 2553 was “spinning rapidly and likely out of control,” CEO Marco Rocchetto told Newsweek magazine. This could pose a “serious setback” if the satellite were supporting a nuclear anti-satellite program, he said.
This observation strongly suggests the satellite is no longer operational, according to the “Space Threat Assessment 2025” report from the Center for Strategic and International Studies (CSIS), a Washington, D.C.-based think tank.
Cosmos 2553 is thought to be a radar satellite for Russian intelligence as well as a radiation testing platform. While Cosmos 2553 was not thought to be a weapon, the satellite in 2024 became the center of U.S. assertions that Russia has been developing a nuclear space weapon, potentially using the satellite’s platform to develop a weapon capable of destroying entire satellite networks.
Russia has claimed Cosmos 2553’s mission is to test on-board instruments in a high-radiation environment, “but this does not align with its characteristics,” a U.S. Space Command spokesperson told Reuters. “This inconsistency, paired with a demonstrated willingness to target U.S. and Allied on-orbit objects, increases the risk of misperception and escalation,” the spokesperson said.
A space weapon with nuclear capabilities would be a breach of the 1967 Outer Space Treaty, which prohibits signatory nations from stationing nuclear weapons in space. While not directed at Earth, such a weapon would destroy or disable thousands of space assets in low Earth orbit (LEO), roughly 100 kilometers to 2,000 kilometers in altitude. The post-explosion radiation and debris could render LEO risky for space assets, including commercial satellites used for communication, transportation and weather tracking, for years.
Cosmos 2533 is one of dozens of Russian satellites in space with suspected ties to the military. In May 2024, Moscow launched Cosmos 2576 to an orbital plane that U.S. officials said allows it to observe — and potentially attack — U.S. space assets, specifically a U.S. government satellite. While not a nuclear weapon, U.S. officials said the satellite is likely a counterspace weapon designed to disable or destroy U.S. space capabilities. The U.S. said the satellite had “characteristics resembling previously deployed counterspace payloads.”
As of February 2025, Cosmos 2576 had raised its orbit and was no longer operating in a synchronized orbit with any U.S. satellites, according to the CSIS report. Russia has launched at least three additional satellites so far in 2025, saying only that the spacecraft belong to its ministry of defense, according to the report.