Complex sentence: Hughes Space and Communications Group and the Hughes Space Systems Division built the world's first geosynchronous communications satellite, Syncom, in 1963 and followed it closely with the first geosynchronous weather satellite, ATS-1, in 1966.
Split into simpler sentences: Hughes Space and Communications Group and the Hughes Space Systems Division. This division built the world's first geosynchronous communications satellite, Syncom, in 1963 and followed it closely with the first geosynchronous weather satellite, ATS-1, in 1966.