Russian satellite appears to be stalking a classified US military satellite in a cat-and-mouse chase. The US satellite just pushed itself a bit higherIn the latest development of this game of orbital hide-and-seek, the US satellite jumped to a higher orbit, climbing farther away just before Kosmos-2558 was set to pass close by again on April 7, according to hobby satellite tracker Nico Janssen. Between the sun and orbital spies, "satellites are very vulnerable," Janssen said