Open-source orbital tracking data revealed that four Russian satellites have expended considerable fuel to approach an American-Finnish satellite. According to Integrity ISR (via LinkedIn), a U.S.-based defense and intelligence firm, Russian assets closed in on ICEYE-36, a radar satellite operated by ICEYE that delivers reconnaissance data to U.S. and European governments — including Ukraine, which uses the data as it defends itself against Russian aggression.
The satellites executed co-planar maneuvering, placing them in the same orbital plane as ICEYE. The biggest concern here is that this maneuver is the first step in Rendezvous Proximity Operations (RPO), an operation in which one spacecraft (or a set, in this case) changes its flight path to get close to another. More concerningly, this move consumes a lot of fuel, with ISR saying it isn’t common for earth observation, signals intelligence, or communications. A fifth satellite is also reportedly making the same fuel-intensive move to match the orbital plane of the four other satellites.