spacewatching:

The
orbiter Columbia, aboard its orbiter transporter system, rolls toward
the opening in the Vehicle Assembly Building where it was mated with the
external tank mating in preparation for mission STS-93. The primary
mission objective was the deployment of the Advanced X-ray Astrophysics
Facility, renamed the Chandra X-Ray Observatory. Mission STS-93 was the
first led by a woman, Commander Eileen M. Collins.  The mission launched
on July 23, 1999.