The Exposed Facility has been attached to the Kibo laboratory module, giving the International Space Station a new outdoor platform to perform science research. The external deck is the third and final piece for Japan's segment of station to be launched and installed.

Known as the JEF, the Japanese Exposed Facility is the porch that supplies power, data and thermal cooling to small payloads. The deck is capable of accommodating up to nine experiments in Earth studies, space environment monitoring, materials processing and astronomy. It also can and will support communications gear.

Three packages still in Endeavour's payload bay will be installed on JEF later in the mission.

"The Japanese Exposed Facility, or "Jeff" as we tend to call it, is very impressive. It's a large external porch to the space station where high quality experiments can be conducted in high vacuum of space. It's really an exceptionally valuable piece of real estate being produced in outer space. It has its own robotic arms, the ability to do observations of the Earth and of the sky, astrophysics experiments, a very wide range of abilities," says astronaut Dave Wolf.

The other two elements of the station's Japanese segment include the large Kibo laboratory module and an attic-like logistics module, both of which were launched last year.

The crew aboard the space station is having some trouble with a scopemeter. That's delaying completion of the Exposed Facility installation sequence.

Mission Control says the four latches have been closed. Four bolts will be driven to finish the attachment process.

A soft capture has been achieved.

The "go" has been given to close the capture latches.

Mission Control reports good alignment between the platform and Kibo. The two are about to be permanently connected to each other 220 miles above the planet.

The station arm is moving the exposure platform toward its berthing port on the Kibo module at a glacial pace.

EVA ENDS. Repressurization of the Quest airlock module began at 5:51 p.m. EDT, marking the official end of today's spacewalk by Dave Wolf and Tim Kopra. The EVA lasted five hours and 32 minutes. It was the first of five spacewalks planned for Endeavour's construction mission to the international space station.

The outer hatch has been closed and locked.

The spacewalking duo has climbed into the airlock and will soon close the hatch to complete this successful first EVA of Endeavour's STS-127 flight.

The spacewalkers have been given approval to ingress the airlock as the EVA winds down.

The Exposed Facility is getting closer and closer to its attachment point on the station. The Kibo module has the active half of the berthing mechanism. Four capture latches and four motor-driven bolts on Kibo will attach the external deck to the station.

Endeavour's arm has released the Exposed Facility to the space station arm for final maneuvering and attachment onto Kibo.

The spacewalkers plan to use the remaining time on this EVA to install some covers on the system that routes power from the space station to docked shuttles.

About two hours after leaving the Exposed Facility in the hands of the shuttle robot arm, the space station's arm has again gappled the Japanese payload.

The spacewalkers have finished setting up that payload bracket. They had planned to deploy another one on the starboard side of the station today. However, there's not going to be enough time left to jump into that task on this EVA.

After anchoring its free hand onto the mobile base system, the station arm released its other end from the Harmony node. The arm will grapple the science deck from the shuttle arm shortly.

The special tool developed in light of problems deploying an external space station payload bracket during the last shuttle mission has worked, the astronauts report. The spacewalkers were able to free a jam that had prevented the structure from being deployed on the Port 3 truss.

The so-called Unpressurized Cargo Carrier Attachment System will house a pallet of spare parts to be launched aboard a future shuttle mission.

The shuttle arm has put the Exposed Facility in the next handoff position for the station arm to retake the payload.

Next for the spacewalkers will be work on the Unpressurized Cargo Carrier Attachment System at the Port 3 truss. This external payload bracket got stuck during deployment efforts on the previous shuttle mission. Wolf and Kopra are armed with a new tool that engineers hope will successfully get the structure unfolded.

The space station arm has completed its end-over-end relocation inch-worm style from the Harmony module to the mobile base railcar. The arm will take back the Japanese Exposed Facility, which is being swung into position for handoff by the shuttle's robot arm.

Now three hours into this first spacewalk of Endeavour's mission. En route back from the payload bay, Kopra's to-do list included adjusting covers on the berthing ports of the Harmony and Unity nodes.

Read our update story on the progress of today's EVA.

The station's robot operated from inside the Destiny laboratory by Doug Hurley and Koichi Wakata has let go of the Japanese Exposed Facility. The arm will relocate itself in preparation for installing the platform. As the station arm is being moved, the shuttle arm will slowly maneuver the payload to the next handoff location.

While Tim Kopra buttons up the tool box in Endeavour's payload bay, Dave Wolf has been adjusting one of the Cew Equipment Translation Aid carts along the station rail tracks to keep it clear of the port-side solar array rotation joint.

The Japanese Exposed Facility is now in the hands of both the shuttle and station arms.

The shuttle's arm, operated by Mark Polansky and Julie Payette, is reaching over to grapple the Japanese Exposed Facility.

The 8,372-pound Japanese Exposed Facility has been maneuvered over the port wing of Endeavour by the space station's robot arm. The platform will be handed off to the shuttle's arm, enabling the station arm to relocate itself from the current operating base on the Harmony node to the mobile railcar in order to install the payload this afternoon.

Wolf is now releasing some bolts on a grapple bar for the port-side ammonia tank assembly, an effort to save time for a future crew.

Tim Kopra is now working to release power cables between the shuttle bay and a cargo carrier loaded with spare parts destined for the space station. That carrier will be unberthed and moved to the station tomorrow.

Unberthing of the Japanese Exposed Facility from the payload bay is underway.

The umbilical that has fed power from shuttle Endeavour to the Japanese Exposed Facility in the payload bay has been disconnected by spacewalker Tim Kopra. The power was used by the launch-to-activation heaters.

The spacewalkers have now completed their work on the Japanese Exposed Facility for today. Unhooking the cable frees the platform for the astronauts inside the spacecraft to remotely command the retension latches to open up and the station arm to unberth the payload for attachment to the Kibo lab module later this afternoon.

The rest of today's EVA will be spent on an assortment of other tasks.

The thermal cover that Dave Wolf has removed from Kibo's berthing mechanism a little while ago was just thrown overboard by the spacewalker.

Wolf is now adjusting a couple of tabs on the Japanese robot arm that were obstructing the view of its video camera.

Meanwhile, Wolf is working on the outer end of the Kibo laboratory module to remove the thermal blanket covering the berthing port where the science deck will be attached.

These covers are extracted by releasing four fasteners. Wolf will jettison his overboard while Kopra packs his away inside a payload bay tool box.

Kopra's first task on the Exposed Facility is uncovering the science platform's attachment fixture. The spacewalker will pull off a thermal cover and stow the blanket.

Spacewalker Tim Kopra is climbing hand-over-hand from the space station down to the payload bay of space shuttle Endeavour.

Dave Wolf is embarking on the fifth spacewalk of his career. Now outside of the airlock, Wolf will head over to the Kibo laboratory module to prep the site where the Exposed Facility will be installed later today.

Tim Kopra has emerged from the airlock at the start of his first spacewalk. He'll be heading down into the payload bay of space shuttle Endeavour to ready Japan's Exposed Facility for removal.

EVA BEGINS. The spacewalkers switched their suits to internal battery power at 12:19 p.m. EDT, marking the official start time for today's EVA by Dave Wolf and Tim Kopra. This is the first of five spacewalks planned during Endeavour's mission at the International Space Station.

Depressurization has been completed and the Quest airlock's outer hatch leading to space is being opened.

Depressurization is pausing at 5.0 psi for a planned leak check.

Airlock depressurization has started.

The internal hatch on the airlock has been closed.

Dressed in their spacewalking suits and ready to head outside today, Dave Wolf and Tim Kopra have moved into the section of the airlock that will be depressurized a short time from now.

Spacewalk preps are running a little behind schedule at this point. So the EVA will start sometime after 12 noon EDT.

Final steps in the suitup process are being completed in the Quest module now. The spacewalkers are being outfitted with the SAFER backpacks that would enable an untethered astronaut to fly back to the station.

Meanwhile, the space station's robot arm has reached into Endeavour's payload bay and grappled the Japanese Exposed Facility. Removal of the payload won't occur until during the spacewalk because the astronauts have to manually unhook umbilicals and pull off a thermal cover.

Astronauts David Wolf and Timothy Kopra are preparing for a spacewalk today, the first of five planned by the Endeavour astronauts, to ready an experiment platform for attachment to the Japanese Kibo laboratory module.

Read our preview story.

The big day of space shuttle Endeavour's construction mission to the International Space Station has begun. Houston woke up the astronauts a moment ago to start Flight Day 4.

The mission's primary payload -- Japan's Exposed Facility -- will be hoisted out of Endeavour's cargo bay and installed onto the station's Kibo science laboratory. Preps to unberth the large platform will be performed at the start of today's six-and-a-half-hour spacewalk by Dave Wolf and Tim Kopra. The EVA is scheduled to get underway shortly before 12 noon EDT.

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Read our earlier status center coverage.