STS-28 was the fourth shuttle mission dedicated to United States Department of Defence purposes, and the first flight of Columbia since STS-61-C. The details of the mission are classified, but the payload is widely believed to have been the first SDS-2 communications satellite. The mission launched successfully on August 8, 1989, lasted just over 5 days, and travelled 2.1 million miles over 81 Earth orbits. Read more