(06/23/1999) -- Inside the 'White Room' at Launch Pad 39B, the STS-93 crew poses for a photo before passing through the hatch on the orbiter Columbia. In the back row are Pilot Jeffrey S. Ashby, Commander Eileen M. Collins and Mission Specialist Michel Tognini of France, who represents the Centre National d'Etudes Spatiales (CNES). Kneeling in front are Mission Specialists Steven A. Hawley (Ph.D.), and Catherine G. Coleman (Ph.D.). The White Room is an environmentally controlled chamber that abuts the orbiter hatch. In preparation for their mission, the STS-93 crew members are participating in a Terminal Countdown Demonstration Test, which familiarizes them with the mission, provides training in emergency exit from the orbiter and launch pad, and includes a launch-day dress rehearsal culminating with a simulated main engine cut-off. The primary mission of STS-93 is the release of the Chandra X-ray Observatory, which will allow scientists from around the world to obtain unprecedented X-ray images of exotic environments in space to help understand the structure and evolution of the universe. The targeted launch date for STS-93 is no earlier than July 20 at 12:36 a.m. EDT from Launch Pad 39B