13 September 1985
13 September 1985: Major Wilbert D. Pearson, U.S. Air Force, flying McDonnell Douglas F-15A-17-MC, 76-0084, Celestial Eagle, launched an anti-satellite missile in a test, approximately 200 miles (322 kilometers) west of Vandenberg Air Force Base, on the central coast of California.
From level flight at Mach 1.22, Major Pearson pulled into a 3.8 G zoom to a 65° angle of climb. On reaching 38,100 feet (11,613 meters) and having slowed to 0.934 Mach, the LTV ASM-135 missile was automatically launched. At 1:42 p.m. Pacific Daylight Time, the 30 pound (13.6 kilogram) kinetic interceptor collided with the Solwind P78-1 satellite at an altitude of 345 miles (555 kilometers) and a closing speed of 15,000 miles per hour (21,140 kilometers per hour).
Solwind P78-1 was an Orbiting Solar Observatory satellite built by Ball Aerospace & Technologies Corp., of Broomfield, Colorado. The satellite had been launched from Vandenburg Air Force Base, 24 February 1979, and was in an almost circular orbit. P78-1 weighed 1,870 pounds (848 kilograms). Degraded batteries had made the satellite difficult to work and it was planned to terminate the mission when it was selected as the target for the ASAT.
