KENNEDY SPACE CENTER, FL--The Atlantis astronauts are working through a busy day of heat shield inspections, docking preparations and rendezvous rocket firings to fine tune the orbiter's approach to International Space Station. Docking is targeted for 11:07 a.m. EDT (GMT-4) Sunday.

An artist's concept of Atlantis' heat shield inspections planned for today. Credit: NASA TV

Space shuttles normally fly with crews of six or seven, but just four are flying aboard Atlantis -- commander Christopher Ferguson, pilot Douglas Hurley, Sandra Magnus and Rex Walheim -- to minimize rescue scenarios in case of a major problem that might prevent a safe re-entry. But on the flip side, there are fewer hands available to do the same amount of work.

"It will be challenging to get through that inspection with a reduced crew complement," said Flight Director Kwatsi Alibaruho. "But this crew has practiced considerably to be able to develop a flow or a routine, if you will, to where even though they have fewer hands available in the shuttle they'll be able to get through these inspections in the timeframe that's been allotted."

The astronauts planned to spend most of their day Saturday inspecting the shuttle's heat-resistant nose cap and wing leading edge panels to make sure no damage was incurred during launch Friday. Using an instrumented boom attached to the end of Atlantis' 50-foot-long robot arm, the astronauts planned to inspect the right wing first, followed by the nose cap and then the left wing.

"The orbiter boom sensor system, the OBSS, will be maneuvered into position to start survey of the starboard wing," said Alibaruho. "There, the various sensor packages on the OBSS, which include a high-resolution still camera, a laser range imager as well as a video camera, will sweep over the critical surfaces of Atlantis' thermal protection system, looking for any imperfections, any damage that might have been caused by ascent debris or anything that might compromise Atlantis' capability to perform a safe re-entry.

"After inspecting the wing leading edge and also areas of the (right-side) payload bay door, the OBSS will inspect the nose cap, which is also made of the same reinforced carbon carbon material that's on the leading edge of the wings. Once that inspection is complete, the OBSS will move to the port wing and conduct similar inspections there, again, looking for imperfections, orbital debris damage, ascent debris damage and anything we might need to go address.

"We'll conclude by inspecting the port payload bay door as well as some of the areas where umbilicals were attached prior to launch."

Along with the heat shield inspections, Ferguson and Hurley planned to carry out two rendezvous rocket firings to refine Atlantis' orbit and approach to International Space Station. The astronauts also planned to check out laser range finders and other rendezvous tools that will be used during final approach to the station Sunday.

A mission status briefing is planned at 2 p.m., followed by a mission management team briefing at 4 p.m. to review launch and any issues that might be under discussion.

Here is an updated timeline of the crew's planned activities for flight day five (in EDT and mission elapsed time; includes revision B of the NASA television schedule; best viewed with fixed-width font):

DATE/EDT...DD...HH...MM...SS...EVENT

07/09
03:59 AM...00...16...30...00...Crew wakeup
06:11 AM...00...18...42...02...NC-2 rendezvous rocket firing
07:04 AM...00...19...35...00...OBSS unberth
07:29 AM...00...20...00...00...Ergometer setup
08:19 AM...00...20...50...00...OBSS starboard wing survey
10:14 AM...00...22...45...00...Crew meals begin
11:14 AM...00...23...45...00...OBSS nose cap survey
11:49 AM...01...00...20...00...Middeck transfer preps
12:04 PM...01...00...35...00...OBSS port wing survey
02:00 PM...01...02...31...00...Mission status briefing on NASA TV
02:19 PM...01...02...50...00...SRMS berths OBSS
02:34 PM...01...03...05...00...Laser scan data downlink
02:39 PM...01...03...10...00...Spacewalk equipment preps
03:24 PM...01...03...55...00...Rendezvous tools checkout
03:29 PM...01...04...00...00...Centerline camera install
03:59 PM...01...04...30...00...Orbiter docking system ring extension
04:00 PM...01...04...31...00...MMT briefing on NASA TV
04:39 PM...01...05...10...00...Airlock prep
05:27 PM...01...05...58...19...NC-3 rendezvous rocket firing
07:29 PM...01...08...00...00...Crew sleep begins
09:00 PM...01...09...31...00...Flight day 2 highlights on NASA TV
11:00 PM...01...11...31...00..."Launching Our Dreams" replay on NASA TV

Additional coverage for subscribers:
VIDEO: COUNTDOWN PREVIEW AND WEATHER FORECAST BRIEFING PLAY
VIDEO: ASTRONAUTS ARRIVE AT LAUNCH SITE PLAY
VIDEO: PRE-FLIGHT INTERVIEW WITH CHRIS FERGUSON PLAY
VIDEO: PRE-FLIGHT INTERVIEW WITH DOUG HURLEY PLAY
VIDEO: PRE-FLIGHT INTERVIEW WITH SANDY MAGNUS PLAY
VIDEO: PRE-FLIGHT INTERVIEW WITH REX WALHEIM PLAY

VIDEO: SHUTTLE AND STATION PROGRAM BRIEFING PLAY
VIDEO: THE STS-135 MISSION OVERVIEW PRESENTATIONS PLAY
VIDEO: PREVIEW BRIEFING ON MISSION'S SPACEWALK PLAY
VIDEO: THE ASTRONAUTS' PRE-FLIGHT NEWS BRIEFING PLAY

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