Researchers have traced mysterious, seconds-long bursts of GPS interference across Europe to Russian satellites in the EKS early-warning constellation — raising alarms that space-based navigation jamming could soon reach continental scale.
The findings come from a June 2 preprint paper by Todd Humphreys and Zach Clements at the University of Texas at Austin, alongside Argyris Krizise at Stanford. By analyzing public ground-station GNSS data spanning from January 2019 to April 2026, the team identified 75 separate days with widespread interference events hitting the GPS L1 frequency band at 1575.42 MHz.
How They Tracked the Signal to Space
The interference was short — under 10 seconds per burst — but simultaneously detectable from Norway to Spain to Poland, and as far west as Greenland and Canada. That geographic spread was the key clue. Humphreys calculated that the source had to sit at least 1,200 kilometers above Earth, effectively ruling out ground-based jammers.
The breakthrough came in February 2026 when amateur radio operators in Amsterdam and Trondheim, Norway captured raw signal data during a live interference event. By measuring the nanosecond-level timing difference between when the signal hit each station, the team reconstructed a “quasi-hyperboloid” surface stretching tens of thousands of kilometers into space — with a margin of error of just five meters.
Only one satellite’s orbit matched perfectly: Kosmos 2546, one of six spacecraft in Russia’s Edinaya Kosmicheskaya Sistema (EKS) constellation. These satellites use highly elliptical Molniya orbits optimized for long-duration coverage of the northern hemisphere, originally designed to detect ballistic missile launches.
Accident or Capability?
The big question now is whether this is intentional jamming or an unintended side effect of the satellites’ onboard systems. The researchers haven’t concluded either way. But the pattern is suspicious: interference events clustered on Tuesdays, Wednesdays, and Thursdays during European business hours, suggesting deliberate scheduling rather than random noise.
There’s also a practical concern. If Russia can already produce GPS-deniable effects across an entire continent — even in short bursts — the same infrastructure could theoretically be scaled for longer, more targeted attacks. GPS underpins everything from commercial aviation and shipping to telecom synchronization and financial trading timestamps.
What This Means Going Forward
The US Space Force and European GNSS agencies are likely already evaluating countermeasures, including hardened receivers and alternative navigation signals. But this discovery exposes a vulnerability that many assumed was theoretical rather than demonstrated.
Expect renewed investment in GPS backup systems — and in the broader conversation about the militarization of space-based navigation infrastructure that billions of people rely on every day.
