There was one surplus External Tank left over when the Shuttle program ended, due to some unusual timing, and for some time it’s had an ultimate destination planned: the California Science Center, where it will join Endeavour and a pair of mockup SRBs. Endeavour currently is sitting horizontal on the support structure that tied into its ET attach points and was used to move it from LAX to the museum, mounted on a set of remote-control heavy-duty dollies. Its sheltered by a very utilitiarian temporary hangar. But that’s not its intended final setting. California Science Center has all along planned to display it as if ready for launch. It’ll be an epic display, and the only one showing an entire Shuttle stack with a real ET and a real Orbiter, with a real payload (the payload bay doors will be opened, as if the vehicle is being serviced on the pad) — a SpaceHab module that was on display next to Endeavour up until a few months ago, when the Orbiter payload bay was opened to install the module.
The External Tank is of course a vital element of this vertical display concept, as the ET carries the full weight of the Orbiter while sitting on the pad. That final External Tank is rolling out of the Michoud facility in Louisiana. It will board NASA’s Pegasus barge, which ferried all the other External Tanks to Florida, for a very special trip south, through the Panama Canal, up the Mexican coast, past Baja California, and then to the port of Los Angeles. It will then be offloaded and shipped through town over city streets to the California Science Center. There was such a great turnout for the cross-town ferry of Endeavour that the city of Los Angeles is thinking about making an event out of the External Tank delivery too. So stay tuned. 😉