STS-93 Commander Collins and Pilot Ashby working on the middeck of Columbia

STS093-309-027 (23-27 July 1999) ---
Astronauts Eileen M. Collins, mission commander; and Jeffrey S. Ashby, pilot,
peruse checklists on Columbia's middeck.
Collins and Ashby were joined by three mission specialists for almost five days in Earth orbit. The busiest of those days was the first, during which they
released into space the world's most powerful X-Ray telescope and initiated a number of in-cabin experiments.