The 73d Space Group is an inactive United States Air Force space surveillance organization. Its last assignment was with Fourteenth Air Force, being stationed at Falcon Air Force Base, Colorado. It was inactivated on 26 April 1995. The Group performed space surveillance. In April 1995 the 73d Space Surveillance Group merged with the 21st Space Wing. From that point the 21st became the largest wing in the United States Air Force with units deployed literally throughout the world.