LOS ANGELES (CBSLA.com) — If you’ve ever wanted to know what the payload bay of a Space Shuttle looks like, this could be your last chance.

KNX 1070’s Ron Kilgore reports the installation marks the first time the payload bay doors of an operational orbiter have been
opened anywhere except at the Kennedy Space Center or the Palmdale assembly facility.

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In September 2012, millions of Angelenos witnessed the final flight of Space Shuttle Endeavour over California landmarks and her 12-mile, 68-hour journey through city streets to her final destination in the Samuel Oschin Pavilion at the California Science Center.

Now, Endeavour faces three more stages leading up to her lift into the vertical launch position in 2018: “Go for Payload,” “Go for Stack” and “Go for Launch”.

The “Go For Payload” operation underway Thursday installed a flown SPACEHAB unit – which served as extra room for astronauts in which to live and work – and other equipment into Endeavour’s payload bay.

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Since the payload bay doors are made of very lightweight composite material and were not designed to be operated on Earth under its gravitational influence, the operation required specific equipment and procedures to operate safely, according to officials.

The operation also marks the last time a payload will be installed in a Space Shuttle.

The configuration resembles the payload carried on STS-118 when teacher and astronaut Barbara Morgan and her fellow crew members conducted numerous education programs involving students on the ground and also continued assembly of the International Space Station, according to California Science Center Aerospace Science Curator Kenneth Phillips.

“We’re replicating Endeavour’s payload bay to represent [Morgan’s] flight,” said Phillips.

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The “Go For Payload” exhibit opens Thursday and runs through Oct. 25.