Atlantis and its crew are returning home from the International Space Station (ISS) after seven days docked to the orbiting laboratory, where they installed a new Russian research module and changed out six solar array batteries over the course of three spacewalks. The shuttle launched on May 14 and undocked from the orbiting lab on Sunday.

To prepare for their return, Atlantis' commander Ken Ham, pilot Dominic "Tony" Antonelli and mission specialists Piers Sellers, Garrett Reisman, Stephen Bowen and Michael Good spent Monday morning using the shuttle's robotic arm and its 50-foot extension boom to conduct a routine "late inspection" of the orbiter's thermal protection system tiles and reinforced carbon-carbon surfaces, including the wing leading edges and nose cap.  

The inspection is to ensure Atlantis was not damaged by micrometeroids while docked to the station, but it will also provide analysts on the ground with the chance to add to the abbreviated survey data that was collected earlier in the mission after a cable snag prevented the use of the extension's primary camera system.

Reisman and Bowen cleared the snag during the mission's second spacewalk, so the boom and its associated sensor package was fully operational for today's survey. Other imagery and engineering data was used to fill in gaps in the post-launch inspection.

"We've convinced ourselves, as a team, through all of the launch imagery that we've recovered via the solid rocket boosters recently, as well as the standard launch imagery,  the wing leading-edge sensors, the [modified] flight day two inspection that we got via the digital camera on the orbiter boom sensor system, the rendezvous pitch maneuver images and then images obtained during the first spacewalk that Atlantis and its tile are ready to go and we just need to do the standard orbital debris inspection," explained lead shuttle flight director Mike Sarafin.

Space shuttle inspections have been standard parts of every mission since heat shield damage led to the tragic loss of shuttle Columbia and its crew in 2003. Atlantis' heat shield has already received a clean bill of health after two earlier surveys during this mission. Today's inspection is the final look at the heat shield to make sure nothing has changed while Atlantis has been in space.

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