The satellite to rockets manufacturer Orbital ATK has revealed that it is currently building a third pair of GSSAP (Geosynchronous Space Situational Awareness programme) satellite surveillance satellites for the US Air Force. These satellites, of which four have been launched to date, move around the geostationary orbit imaging and inspecting other satellites for the purpose of intelligence gathering.
Comment by David Todd: Seradata assumes that a construction order was made in early 2017. No launch date has been revealed, however, previous GSSAP spacecraft have only taken around 2-3 years to build so a launch in the 2019-20 timeframe may be likely.