(04/29/1999) --- In the white room, an environmental chamber at Launch Pad 39B, Mission Specialist Tamara E. Jernigan (Ph.D.) gets ready to enter the orbiter Discovery. Helping her with her equipment are (left to right) Mike Birkenscher, Travis Thompson and James Davis. The STS-96 crew are taking part in Terminal Countdown Demonstration Test (TCDT) activities, which provide opportunities to inspect the mission payloads in the orbiter's payload bay, as well as simulated countdown exercises and emergency egress training. Other crew members are Commander Kent V. Rominger, Pilot Rick Douglas Husband, and Mission Specialists Ellen Ochoa (Ph.D.), Daniel Barry (M.D., Ph.D.), Julie Payette, who is with the Canadian Space Agency, and Valery Ivanovich Tokarev, who is with the Russian Space Agency. STS-96, scheduled for liftoff on May 20 at 9:32 a.m., is a logistics and resupply mission for the International Space Station, carrying such payloads as a Russian crane, the Strela; a U.S.-built crane; the Spacehab Oceaneering Space System Box (SHOSS), a logistics items carrier; and STARSHINE, a student-led experiment