External tank No. 123 heads toward the open doorway of the Vehicle Assembly Building.

External tank No. 123 heads toward the open doorway of the Vehicle Assembly Building. Once inside the VAB, the tank will be lifted into a checkout cell for further work. Shipped from NASA's Michoud Assembly Facility in New Orleans aboard the Pegasus barge, the tank has undergone major safety changes, including removal of the protuberance air load ramps. It is designated to launch Space Shuttle Discovery on mission STS-116 in December. Mission STS-116 will deliver the P5 truss segment, a SPACEHAB module and other key components to the International Space Station. Launch is currently scheduled no earlier than Dec. 14. Photo credit: NASA/Jack Pfaller