Launch from Cape Canaveral (KSC) after two delayed launches due of technical problems (abort on July 20, 1999) and bad weather (on July 22, 1999). Landing on Cape Canaveral (KSC). Columbia did not reach the planned orbit. Five seconds after liftoff, an electrical short disabled one primary and one secondary controller on two of the three main engines. In this event, the engines automatically switched to their backup controllers. The short was later discovered to have been caused by poorly routed wiring which had rubbed on an exposed screw head.

The X-Ray-telescope CHANDRA was deployed on flight day 1. CHANDRA was the most sophisticated X-ray observatory ever built. It is designed to observe X-rays from high energy regions of the universe, such as hot gas in the remnants of exploded stars. In addition the crew did scientific work with the Southwest Ultraviolet Imaging System (SWUIS). Eileen Collins became the first female Shuttle commander. Several secondary payloads.