Ah, this is another one the Russians also sent up.
"Russia just launched a mysterious satellite that could be spying on an even more mysterious U.S. military satellite, with the Russian spacecraft predicted to make a close approach to its presumed target this coming Thursday.
Before it launched on Monday, speculation already existed that the Russian satellite would be considered a so-called
“inspector” satellite—one that stalks other satellites to sneak a closer look. The spy satellite, poised to receive the designation Kosmos 2558, launched into the same orbital plane as a U.S. military satellite, dubbed USA 326, that flew to space in February. Marco Langbroek, an astrodynamics lecturer at Delft Technical University in the Netherlands, tracked the orbital plane of the two satellites and found that the Russian satellite was launched at a time that coincided with the U.S. satellite passing over the Russian spaceport Plesetsk."
https://gizmodo.com/newly-launched-russian-spy-satellite-might-be-stalking-1849366620