A Russian satellite believed to be part of Moscow’s nuclear anti-satellite weapon program appears to be malfunctioning, with erratic movements suggesting it may no longer be operational. The development could be a major blow to Russia’s military space ambitions, US analysts said.
Cosmos 2553 was launched just weeks before Russia invaded Ukraine in 2022. Over the past year, it has shown signs of uncontrolled tumbling, according to radar data from LeoLabs and optical tracking shared by Slingshot Aerospace with Reuters.
The satellite is believed to serve as both a radar tool for intelligence gathering and a platform for radiation testing. While Cosmos 2553 is not considered a weapon itself, US officials say it plays a key role in testing technologies for a potential nuclear weapon designed to disable or destroy entire satellite constellations — such as the Starlink system that has been instrumental for Ukrainian forces.
Russia denies any intention to develop such weapons and claims the satellite’s mission is purely scientific.
A strategic setback in space
If Cosmos 2553 has indeed failed, the malfunction would represent a setback in Russia’s efforts to militarize space. A storied space power since launching the first human into orbit in 1961, Russia has shifted focus in recent years toward space security as tensions rise with the United States and China.
The satellite was deployed into a high-radiation orbit approximately 2,000 kilometers above Earth — a zone typically avoided by communication and Earth-observing satellites due to the extreme radiation environment.
LeoLabs first detected anomalies in November using Doppler radar data collected from its global network. By December, the company had upgraded its analysis to “high confidence” that the satellite was tumbling, based on new radar inputs and additional satellite imagery.
Russia’s Defense Ministry did not respond to a request for comment.
“This observation strongly suggests the satellite is no longer operational,” said the Center for Strategic and International Studies in its latest Space Threat Assessment.
Signs of instability followed by possible stabilization
US Space Command, which monitors space objects and has previously criticized Russian military behavior in orbit, confirmed awareness of a shift in Cosmos 2553’s altitude. It declined, however, to provide further analysis of the satellite’s current condition.
Slingshot Aerospace, which has tracked the spacecraft since its February 5, 2022, launch, observed irregular behavior in May 2024. “The object’s brightness became variable, indicating a potential tumble,” a company spokesperson said.
More recent observations suggest that the satellite may have stabilized, according to Slingshot’s chief science officer, Belinda Marchand. It remains unclear, however, whether the satellite is still functional or has been compromised.
Rising risks of miscalculation in orbit
With the number of civil and military satellites in space growing rapidly, commercial space-tracking services like LeoLabs and Slingshot have become increasingly important for national defense agencies seeking to avoid misinterpretations that could lead to escalation.
The US Defense Department has prioritized enhanced orbital awareness to better understand whether spacecraft belong to civilian, commercial or military systems.
According to a US Space Command spokesperson, Russia has claimed that Cosmos 2553’s mission is to test instruments in a high-radiation environment — but its behavior and characteristics do not match that profile.
“This inconsistency, paired with a demonstrated willingness to target US and allied on-orbit objects, increases the risk of misperception and escalation,” the spokesperson said.
A crowded and contested military frontier
Cosmos 2553 is one of several satellites operated by Russia that US officials believe are tied to military and intelligence programs. Moscow views Starlink — a vast satellite network operated by Elon Musk’s SpaceX — as a legitimate military target due to its battlefield use in Ukraine.
Russia, the US and China are all pouring billions of dollars into secretive space technologies that could be used for military or dual-use purposes. These developments have raised concern over possible misunderstandings and the legal gray zones surrounding conflict in space.
Washington has increasingly acknowledged space as a military domain in recent years, while outsourcing much of its development and operation to private firms like SpaceX.
Mallory Stewart, who served as US assistant secretary of state for arms control and deterrence under President Joe Biden, said in 2023 that Russia was “considering the incorporation of nuclear weapons into its counterspace programs.”
Three US officials told Reuters that the launch of Cosmos 2553 was a key moment in escalating Washington’s concerns about Russia’s nuclear space intentions — and remains a central piece of ongoing US intelligence assessments.