Silentbarker 1

SILENTBARKER/NROL-107 was a joint National Reconnaissance Office and U.S. Space Force mission that placed three space domain awareness satellites - Silentbarker 1, 2, and 3 (USA-346 through 348) - into geosynchronous orbit. The constellation is designed to monitor the GEO belt from space: ground-based radars and telescopes face significant coverage limitations when tracking objects at 36,000 km, and Silentbarker operates in that same orbital regime to search, detect, and track resident space objects continuously.

NROL-107 was the 18th and final NRO payload launched on an Atlas V, with future NRO missions on ULA vehicles transitioning to Vulcan Centaur. The rocket flew in its 551 configuration - five strap-on solid rocket boosters, the vehicle's highest-thrust arrangement.