Running well ahead of schedule, spacewalkers Thomas Marshburn and Christopher Cassidy completed the installation of two critical TV cameras on a Japanese experiment platform to accomplish one of the primary objectives of today's excursion.

But with less carbon dioxide absorbent available in Cassidy's suit than expected, flight controllers told them to forego deploying a payload attachment mechanism and to instead carry out a few minor get-ahead activities before returning to the space station's Quest airlock.

"Congratulations, you guys just completed the JEF assembly," astronaut Aki Hoshide called from mission control after the cameras on the Japanese Exposed Facility were checked out.

"Well, that is a big deal," David Wolf replied from the shuttle-station complex. "You guys have a fabulous apce agency and it's an amazing laboratory, both internal and at vacuum. It's been a privilege to work with you to complete it."

"I can verify from up close, it is indeed a beautiful laboratory," Marshburn agreed.

"Yes, it is," Cassidy said.

"Perhaps among the best (in) space," Wolf concluded.

"Thank you, guys, for getting the porch out," Hoshide said of the exposed facility. "On behalf of JAXA (the Japanese space agency) and the Japanese community, I'd like to thank you guys."

Cassidy and Marshburn already had completed an insulation fix on Canada's DEXTRE construction robot and a re-wiring job on the Z1 truss to put two stabilizing gyroscopes on separate circuits.

They were more than an hour ahead of schedule on their spacewalk timeline when the astronauts and flight controllers agreed to forego the planned deployment of a payload attachment system mechanism on the right side of the station's main power truss.

For today's spacewalk, the astronauts were using a rechargeable chemical known as METOX to scrub carbon dioxide from their air supplies.

"Consumables, METOX for Tom is seven (hours) plus zero zero, METOX for Chris is five plus three zero. Those are non-conservative numbers," Hoshide radioed. "When we did the math on the ground, with the 15 minutes out for cleanup, we're past the bingo time for the PAS deploy. Just wondering what you guys think."

"We'll declare bingo. Simple," Wolf said.

The PAS mechanism must be deployed before a November shuttle mission delivers spare parts and equipment that must be stored at that location. It's not yet clear whether the crew of a late-August shuttle mission will inherit the deployment or whether the station crew will have to take it on.

Today's spacewalk began at 7:33 a.m. EDT, nearly an hour ahead of schedule, when the astronauts switched their spacesuits to internal battery power. They floated out of the space station's Quest airlock a few minutes later.

Additional coverage for subscribers:
VIDEO: MONDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY

VIDEO: FLIGHT DAY 12 HIGHLIGHTS MOVIE PLAY
VIDEO: INTERNATIONAL NEWS CONFERENCE WITH ASTRONAUTS PLAY
VIDEO: SUNDAY'S MISSION STATUS BRIEFING PLAY
VIDEO: SUNDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY
VIDEO: OVERVIEW OF FLIGHT DAY 12 ACTIVITIES PLAY

VIDEO: FLIGHT DAY 11 HIGHLIGHTS MOVIE PLAY
VIDEO: INTERNATIONAL MESSAGE FROM SHUTTLE AND ISS CREWS PLAY
VIDEO: INDY, CBS NEWS AND MEMPHIS MEDIA INTERVIEWS PLAY
VIDEO: SATURDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY

VIDEO: FLIGHT DAY 10 HIGHLIGHTS MOVIE PLAY
VIDEO: FRIDAY'S MISSION STATUS BRIEFING PLAY
VIDEO: DELIVERY PALLET RETURNS TO SHUTTLE PLAY
VIDEO: LAST OF THE OLD BATTERIES STOWED AWAY PLAY
VIDEO: SIXTH AND FINAL NEW BATTERY IS PLUGGED IN PLAY
VIDEO: SPACEWALKERS RESUME WORK WITH BATTERY CHARLIE PLAY
VIDEO: FRIDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY

VIDEO: FLIGHT DAY 9 HIGHLIGHTS MOVIE PLAY
VIDEO: THURSDAY'S MISSION STATUS BRIEFING PLAY
VIDEO: MORE INTERVIEWS WITH LAS VEGAS, HOUSTON AND FOX PLAY
VIDEO: NORTH CAROLINA, MAINE AND ORLANDO TV INTERVIEWS PLAY
VIDEO: COMMUNICATIONS PACKAGE PUT ON SCIENCE DECK PLAY
VIDEO: X-RAY ASTRONOMY PAYLOAD INSTALLED ON STATION PLAY
VIDEO: THURSDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY
VIDEO: OVERVIEW OF FLIGHT DAY 9 ACTIVITIES PLAY

VIDEO: FLIGHT DAY 8 HIGHLIGHTS MOVIE PLAY
VIDEO: WEDNESDAY'S MISSION STATUS BRIEFING PLAY
VIDEO: EARLY END TO SPACEWALK NO. 3 DECLARED PLAY
VIDEO: SECOND FRESH BATTERY PUT INTO STATION TRUSS PLAY
VIDEO: FIRST OF THE NEW BATTERIES INSTALLED PLAY
VIDEO: SPACEWALKERS REMOVE FIRST OLD BATTERY PLAY
VIDEO: CHRIS CASSIDY PREPS JAPANESE EXPERIMENTS PLAY
VIDEO: WEDNESDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY
VIDEO: STEP-BY-STEP SUMMARY OF SPACEWALK NO. 3 PLAY

VIDEO: LEFT-HAND BOOSTER CAMERA LOOKING UPWARD PLAY
VIDEO: LEFT-HAND BOOSTER CAMERA LOOKING INBOARD PLAY
VIDEO: LEFT-HAND BOOSTER CAMERA LOOKING DOWNWARD PLAY
VIDEO: RIGHT-HAND BOOSTER CAMERA LOOKING UPWARD PLAY
VIDEO: RIGHT-HAND BOOSTER CAMERA LOOKING INBOARD PLAY
VIDEO: RIGHT-HAND BOOSTER CAMERA LOOKING DOWNWARD PLAY

VIDEO: FLIGHT DAY 7 HIGHLIGHTS MOVIE PLAY
VIDEO: TUESDAY'S MISSION STATUS BRIEFING PLAY
VIDEO: CREW ANSWERS PUBLIC'S QUESTIONS FROM SPACE PLAY
VIDEO: EXPOSED FACILITY RECEIVES EXPERIMENT CARRIER PLAY
VIDEO: JAPANESE EXPERIMENTS UNBERTHED FROM SHUTTLE PLAY
VIDEO: OVERVIEW OF FLIGHT DAY 7 ACTIVITIES PLAY
VIDEO: TUESDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY

VIDEO: FLIGHT DAY 6 HIGHLIGHTS MOVIE PLAY
VIDEO: MONDAY'S MISSION STATUS BRIEFING PLAY
VIDEO: REPLACEMENT COOLING PUMP PUT ON STATION PLAY
VIDEO: SPARE COMMUNICATIONS ANTENNA TRANSFERRED PLAY
VIDEO: SPACEWALKER HOPS ABOARD STATION ARM PLAY
VIDEO: WOLF AND MARSHBURN BEGIN EVA NO. 2 PLAY
VIDEO: OVERVIEW OF FLIGHT DAY 6 ACTIVITIES PLAY
VIDEO: STEP-BY-STEP SUMMARY OF SPACEWALK NO. 2 PLAY
VIDEO: MONDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY
VIDEO: OVERVIEW OF FLIGHT DAY 6 ACTIVITIES PLAY
VIDEO: STEP-BY-STEP SUMMARY OF SPACEWALK NO. 2 PLAY

VIDEO: FLIGHT DAY 5 HIGHLIGHTS MOVIE PLAY
VIDEO: CANADIANS IN SPACE PLAY
VIDEO: SUNDAY'S MISSION STATUS BRIEFING PLAY
VIDEO: PALLET HANDED OFF TO SPACE STATION PLAY
VIDEO: CARGO CARRIER UNBERTHED FROM SHUTTLE BAY PLAY
VIDEO: SUNDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY
VIDEO: OVERVIEW OF FLIGHT DAY 5 ACTIVITIES PLAY

VIDEO: FLIGHT DAY 4 HIGHLIGHTS MOVIE PLAY
VIDEO: SATURDAY'S MISSION STATUS BRIEFING PLAY
VIDEO: UPDATE ON ENDEAVOUR'S HEAT SHIELD CHECKS PLAY
VIDEO: JAPANESE OUTDOOR SCIENCE PLATFORM ATTACHED PLAY
VIDEO: SHUTTLE AND STATION ARMS HANDOFF SCIENCE DECK PLAY
VIDEO: JAPAN'S EXPOSED FACILITY UNBERTHED FROM SHUTTLE PLAY
VIDEO: THERMAL COVER JETTISONED FROM THE KIBO MODULE PLAY
VIDEO: HELMET-CAMERA VIEWS AS KOPRA CLIMBS TO SHUTTLE PLAY
VIDEO: TIM KOPRA EMERGES FROM AIRLOCK FOR EVA NO. 1 PLAY
VIDEO: SATURDAY MORNING FLIGHT DIRECTOR INTERVIEW PLAY
VIDEO: OVERVIEW OF FLIGHT DAY 4 ACTIVITIES PLAY
VIDEO: STEP-BY-STEP SUMMARY OF SPACEWALK NO. 1 PLAY
VIDEO: NARRATED TOUR OF ENDEAVOUR'S PAYLOAD BAY PLAY

VIDEO: FLIGHT DAY 3 HIGHLIGHTS MOVIE PLAY
VIDEO: FRIDAY'S MISSION STATUS BRIEFING PLAY
VIDEO: SHUTTLE CREW WELCOMED ABOARD STATION PLAY
VIDEO: ENDEAVOUR DOCKS TO THE SPACE STATION PLAY
VIDEO: ASTRONAUTS' ONBOARD CAMCORDER FOOTAGE PLAY
VIDEO: SHUTTLE FLIES OUT IN FRONT OF STATION PLAY
VIDEO: ENDEAVOUR PERFORMS 360-DEGREE BACKFLIP PLAY
VIDEO: BEAUTIFUL VIEWS OF ENDEAVOUR APPROACHING PLAY
VIDEO: STATION CAMERA CATCHES ENDEAVOUR'S "TI BURN" PLAY
VIDEO: NARRATED PREVIEW OF RENDEZVOUS AND DOCKING PLAY

VIDEO: FLIGHT DAY 2 HIGHLIGHTS MOVIE PLAY
VIDEO: TUESDAY'S MISSION STATUS BRIEFING PLAY
VIDEO: PREVIEW ANIMATION OF HEAT SHIELD INSPECTIONS PLAY

VIDEO: FLIGHT DAY 1 HIGHLIGHTS MOVIE PLAY
VIDEO: THE FULL STS-127 LAUNCH EXPERIENCE PLAY
VIDEO: INSIDE MISSION CONTROL DURING LAUNCH PLAY
VIDEO: LAUNCH REPLAY: VAB ROOF PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: PRESS SITE PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: PAD PERIMETER PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: BEACH TRACKER PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: UCS-23 TRACKER PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: PLAYALINDA BEACH PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: PATRICK AIR FORCE BASE PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: BANANA CREEK VIP SITE PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: PAD FRONT CAMERA PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: WEST TOWER PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: CAMERA 070 PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: CAMERA 071 PLAY | HI-DEF
VIDEO: LAUNCH REPLAY: CAMERA CS-1 PLAY
VIDEO: LAUNCH REPLAY: CAMERA CS-2 PLAY
VIDEO: LAUNCH REPLAY: CAMERA CS-6 PLAY

VIDEO: SHUTTLE ENDEAVOUR BLASTS OFF! PLAY | HI-DEF
VIDEO: STS-127 POST-LAUNCH NEWS CONFERENCE PLAY
VIDEO: FOOTAGE OF FUEL TANK AFTER JETTISON PLAY
VIDEO: ASTRONAUTS REACH PAD 39A PLAY | HI-DEF
VIDEO: CREW DEPARTS QUARTERS FOR LAUNCH PAD PLAY | HI-DEF
VIDEO: ASTRONAUTS DON SPACESUITS FOR LAUNCH PLAY | HI-DEF

VIDEO: WEATHER SCRUBS LAUNCH AGAIN PLAY | HI-DEF
VIDEO: CREW ARRIVES AT PAD 39A ON MONDAY PLAY | HI-DEF
VIDEO: CREW DEPARTS QUARTERS ON MONDAY PLAY | HI-DEF
VIDEO: ASTRONAUTS SUIT UP ON MONDAY PLAY | HI-DEF

VIDEO: THUNDERSTORMS SCRUB SUNDAY'S ATTEMPT PLAY | HI-DEF
VIDEO: CREW DEPARTS QUARTERS ON SUNDAY PLAY | HI-DEF
VIDEO: ASTRONAUTS SUIT UP ON SUNDAY PLAY | HI-DEF
VIDEO: NARRATED SUMMARY SHUTTLE'S PREPARATIONS PLAY | HI-DEF
VIDEO: NARRATED SUMMARY PAYLOADS' PREPARATIONS PLAY | HI-DEF

VIDEO: LIGHTNING STRIKES POSTPONE ENDEAVOUR LAUNCH PLAY
VIDEO: FRIDAY'S PRE-LAUNCH NEWS CONFERENCE PLAY
VIDEO: THURSDAY'S STATUS REPORT ON THE COUNTDOWN PLAY
VIDEO: COUNTDOWN PREVIEW AND WEATHER BRIEFING PLAY
VIDEO: ASTRONAUTS RETURN TO CAPE FOR LAUNCH PLAY | HI-DEF

VIDEO: NO LEAKS FOUND DURING SPECIAL TEST PLAY
VIDEO: EXPLANATION OF THE HYDROGEN LEAK AND THE REPAIR PLAY

VIDEO: POST-SCRUB NEWS BRIEFING PLAY
VIDEO: FIRING ROOM UPDATE WITH LAUNCH DIRECTOR PLAY
VIDEO: SCRUB NO. 2 DECLARED DUE TO HYDROGEN LEAK PLAY

VIDEO: SUNDAY'S UPDATE FROM MISSION MANAGEMENT TEAM PLAY
VIDEO: LEAK POSTPONES SHUTTLE ENDEAVOUR LAUNCH PLAY

VIDEO: TIME-LAPSE OF SUN SETTING OVER PAD 39A PLAY
VIDEO: ANOTHER TIME-LAPSE OF GANTRY RETRACTION PLAY
VIDEO: TIME-LAPSE OF LAUNCH PAD TOWER ROLLBACK PLAY

VIDEO: PRE-LAUNCH INTERVIEW WITH MARK POLANSKY PLAY
VIDEO: PRE-LAUNCH INTERVIEW WITH DOUG HURLEY PLAY
VIDEO: PRE-LAUNCH INTERVIEW WITH CHRIS CASSIDY PLAY
VIDEO: PRE-LAUNCH INTERVIEW WITH JULIE PAYETTE PLAY
VIDEO: PRE-LAUNCH INTERVIEW WITH TOM MARSHBURN PLAY
VIDEO: PRE-LAUNCH INTERVIEW WITH DAVE WOLF PLAY

VIDEO: THE STS-127 MISSION PREVIEW MOVIE PLAY
VIDEO: THURSDAY'S PRE-LAUNCH NEWS CONFERENCE PLAY
VIDEO: JAPANESE SCIENCE FACILITIES ABOARD STATION PLAY
VIDEO: COUNTDOWN BEGINS TICKING FOR SATURDAY'S LAUNCH PLAY
VIDEO: LAUNCH COUNTDOWN PREVIEW BRIEFING PLAY
VIDEO: CREW ARRIVES JUST BEFORE MIDNIGHT PLAY | HI-DEF
VIDEO: GET TO KNOW ENDEAVOUR'S ASTRONAUTS PLAY

VIDEO: ASTRONAUTS PRACTICE EVACUATION OF SHUTTLE PLAY | HI-DEF
VIDEO: CREW BOARDS SHUTTLE FOR PRACTICE COUNT PLAY | HI-DEF
VIDEO: ASTRONAUTS SUIT UP FOR DRESS REHEARSAL PLAY | HI-DEF
VIDEO: CREW INSPECTS CARGO IN THE PAYLOAD BAY PLAY | HI-DEF
VIDEO: TRAINING SESSIONS AT LAUNCH PAD AND BUNKER PLAY | HI-DEF
VIDEO: INFORMAL CREW NEWS CONFERENCE AT LAUNCH PAD PLAY
VIDEO: ASTRONAUTS ARRIVE FOR PRACTICE COUNTDOWN PLAY

VIDEO: FLIGHT READINESS REVIEW SETS LAUNCH DATE PLAY

VIDEO: PAD 39A GANTRY ENCLOSES SHUTTLE PLAY | HI-DEF
VIDEO: ROLLAROUND MOVES ENDEAVOUR TO PAD 39A PLAY | HI-DEF
VIDEO: ENDEAVOUR IS HAULED OFF LAUNCH PAD 39B PLAY | HI-DEF
VIDEO: TIME-LAPSE OF SHUTTLE'S LAUNCH PAD SWITCH PLAY

VIDEO: SHUTTLE AND STATION PROGRAM UPDATE PLAY
VIDEO: THE STS-127 MISSION OVERVIEW BRIEFING PLAY
VIDEO: PREVIEW BRIEFING ON MISSION'S SPACEWALKS PLAY
VIDEO: THE ASTRONAUTS' PRE-FLIGHT NEWS BRIEFING PLAY

VIDEO: PAD 39B AND ITS LAST SPACE SHUTTLE PLAY | HI-DEF
VIDEO: ENDEAVOUR'S SUNRISE ARRIVAL AT PAD 39B PLAY | HI-DEF
VIDEO: MIDNIGHT ROLLOUT FROM ASSEMBLY BUILDING PLAY | HI-DEF
VIDEO: ENDEAVOUR HOISTED FOR ATTACHMENT TO TANK PLAY | HI-DEF
VIDEO: CRANE ROTATES ENDEAVOUR VERTICALLY PLAY | HI-DEF
VIDEO: ENDEAVOUR MOVES TO ASSEMBLY BUILDING PLAY | HI-DEF
VIDEO: ORION AND ARES ROCKET PROGRESS REPORT PLAY
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