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... The maneuvers were identified through open source orbital tracking data. Greg Gillinger, a retired Air Force space intelligence officer, revealed the orbit changes Friday in a special edition of his Integrity Flash newsletter, published by Integrity ISR, a private business that provides "combat-proven operational support and elite training that enhances mission success across ISR (Intelligence, Surveillance, and Reconnaissance), cyber, space, and targeting domains."

The Russian satellites in question, designated Kosmos 2610 through 2613, launched together on April 16 on a Soyuz-2.1b rocket from Plesetsk Cosmodrome in northern Russia. Over the last week or so, the four satellites adjusted their inclinations -- the angles of their orbits to the equator -- by less than a degree. ...