The Vehicle Assembly Building the orbiter Atlantis is lowered toward the external tank below.

Inside the Vehicle Assembly Building (VAB), the orbiter Atlantis is slowly lowered toward the external tank below. Visible are the three main engine nozzles, each measuring 7.8 feet across and 9.4 feet high. The 122-foot-long orbiter is easily accommodated inside the 525-foot-tall, 518-foot-wide VAB. After being mated with the tank and solid rocket boosters stack, Atlantis will be transported to Launch Pad 39A. Atlantis will fly on mission STS-101 to the International Space Station, where its crew of seven will prepare the Station for the arrival of the next pressurized module, the Russian-built Zvezda. Atlantis is expected to launch no earlier than April 17, 2000