(AP) -- It's spacewalking day at the shuttle-station complex.
At high noon Saturday, two astronauts will venture out to help attach a platform for science experiments. It's the third and final piece of Japan's huge billion-dollar lab. And it's the first of five spacewalks planned for the shuttle flight.
Endeavour arrived at the international space station Friday, boosting the population for now to a record 13. Before docking, the shuttle performed a backflip for space station cameras. NASA says the analysis is ongoing, but so far Endeavour looks to be in good shape for re-entry at the end of the month.
An unusually large amount of foam broke off Endeavour's fuel tank at liftoff, and some pieces dinged the shuttle.
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