More on the mission from the United Launch Alliance press release:

The twin GSSAP spacecraft, built by Orbital Sciences Corporation, will support U.S. Strategic Command space surveillance operations as a dedicated Space Surveillance Network (SSN) sensor. The GSSAP will also support Joint Functional Component Command for Space (JFCC SPACE) tasking to collect space situational awareness data, allowing for more accurate tracking and characterization of man-made orbiting objects. The satellites will have unobstructed and distinct vantage points for viewing resident space objects orbiting earth without the disruption of weather or atmosphere that can limit ground-based systems. Data from the GSSAP will uniquely contribute to timely and accurate orbital predictions, enhancing our knowledge of the geosynchronous orbit environment and further enabling space flight safety to include satellite collision avoidance.

The GSSAP will communicate information through the world-wide Air Force Satellite Control Network (AFSCN) ground stations, then to Schriever Air Force Base, CO where 50th Space Wing satellite operations will oversee day-to-day command and control operations.

The ANGELS satellite is managed by the Air Force Research Laboratory (AFRL) Space Vehicles Directorate. As part of AFRL’s research in advanced Space Situational Awareness (SSA), ANGELS examines techniques for providing a clearer picture of the environment surrounding our nation’s vital space assets. Launch integration and flight operations of the ANGELS spacecraft are performed in partnership with the Department of Defense (DoD) Space Test Program (STP).