ULA’s Delta 4 Medium launch of the second duo of GSSAP satellites. Photo: USA

[Via Satellite 08-22-2016] United Launch Alliance (ULA) completed its seventh launch of the year on Aug. 19, orbiting the second pair of twin Geosynchronous Space Situational Awareness Program (GSSAP) spacecraft for the United States Air Force. The company used a Delta 4 Medium for the AFSPC-6 mission, which used a common booster core powered with an RS-68A liquid hydrogen/liquid oxygen engine, and a single RL10B liquid hydrogen/liquid oxygen engine for the second stage.

Built by Orbital ATK, the new satellites will join the first two GSSAP spacecraft launched approximately two years ago, also aboard a Delta 4. GSSAP is a space-based capability that collects Space Situational Awareness (SSA) data, allowing for more accurate tracking and characterization of man-made orbiting objects. The satellites support U.S. Strategic Command space surveillance operations as a dedicated Space Surveillance Network (SSN) sensor, as well as the Joint Functional Component Commander for Space (JFCC Space).