SHUTTLE COMMANDER U.S. Air Force Col. Pamela Melroy practices evacuation procedures on her last day of active-duty during training inside the Neutral Buoyancy Lab Jan. 31 at the Johnson Space Center, Houston. Melroy will be the shuttle commander on STS-120 scheduled to launch in September 2007. SHARE: Download: Full Size (0.05 MB) Credit: VIRIN: 010457-I-NVU19-824.jpg Photo Gallery