The orbiter Columbia, aboard its orbiter transporter system, rolls toward the opening in the Vehicle Assembly Building where it will undergo external tank mating operations. Columbia is scheduled for rollout to Launch Pad 39B on Monday, June 7, for mission STS-93. The primary mission objective will be the deployment of the Advanced X-ray Astrophysics Facility, recently renamed the Chandra X-Ray Observatory. Mission STS-93 will be the first Space Shuttle commanded by a woman, Commander Eileen M. Collins. It is scheduled to launch July 22 at 12:27 a.m. EDT although that date is currently under review.