Mission Status Center

Signaling the beginning of the end for NASA's storied shuttle program, the Endeavour plunged back to Earth Wednesday, closing out its 25th and final flight and passing the baton to its sistership Atlantis, which was hauled to the launching pad a few hours earlier for blastoff July 8 on the program's final voyage.

Read our full story.

The launch pad swings arms -- the orbiter access arm, the beanie cap and the external tank access arm -- have been extended. And the crawler just pulled out from beneath the shuttle.

The official numbers for the final space shuttle rollout were first motion at 8:42 p.m. and harddown at 3:29 a.m. EDT.

The mobile launch platform is "harddown" on the pad pedestals, marking the official arrival of Atlantis at pad 39A.

The platform is slowly inching down to the pedestals.

Measurements verify the platform is a good position, so the rollout crew is ready to lower the crawler down.

The Apollo-era crawler has finished tonight's drive from the Vehicle Assembly Building, delivering space shuttle Atlantis atop launch pad 39A. But the rollout's official conclusion time will be marked when the launch platform is lowered down and secured to the pad pedestals.

The crawler is getting the mobile launch platform positioned over the pad pedestals where Atlantis will be perched for the July 8 blastoff.

Atlantis has ascended the incline to launch pad 39A, its crawler-transporter having used massive hydraulic pistons to keep the mobile platform level.

Now atop the pad surface, a precision laser guidance system will help align the platform over the pad pedestals. The crawler will lower the platform onto the pedestals to complete the rollout.

The crawler transporter is climbing the concrete ramp to the launch pad with space shuttle Atlantis.

Atlantis has reached the pad perimeter gate.

The crawler is making the curve to reach the entrance to launch pad 39A.

Atlantis has passed by the Kennedy Space Center's Visitor Center observation gantry as the rollout proceeds smoothly. That's where the crawlerway forks into two pathways - go left to pad 39B or straight ahead to pad 39A.

Check out our photo galleries of Atlantis in the VAB and rolling out tonight.

And the transporter is running again.

The crawler has stopped.

Hauling the shuttle stack out to launch pad 39A on this 3.5-mile trek is one of NASA's two Apollo-era crawler-transporters. The combined weight of the transporter, mobile launch platform and shuttle Atlantis is 17.5 million pounds.

The stone-covered pathway connecting the VAB to the launch pad is 130 feet wide - almost as broad as an eight-lane highway. Two 40-foot-wide lanes are separated by a 50-foot-wide median strip. The average depth is seven feet.

About 30 people are aboard the transporter to operate it during the rollout, including three drivers - a prime and backup in the front cabin and one in the rear - a jacking and leveling operator, a control room operator to run crawler systems and talk with the Launch Control Center, two electricians, two electronic technicians and four diesel mechanics for starting, monitoring and shutting down the transporter's engines. The other team members are mechanics watching over the roll and helping with the platform's docking to the launch pad.

The transporter consumes 126 gallons of diesel fuel in each mile it travels from the VAB to pad. The vehicle has a fuel capacity of 5,000 gallons.

Hit reload for continuing live video from the rollout.

The four-person to crew to fly aboard Atlantis in July is having an informal press conference with reporters here at the Kennedy Space Center. The event is happening just outside our office door at the press site.

Space shuttle Atlantis has emerged from the 52-story landmark Vehicle Assembly Building where it spent the past two weeks getting attached to the external fuel tank and twin solid rocket boosters.

ROLLOUT BEGINS. The crawler-transporter has started moving the space shuttle Atlantis from the cavernous Vehicle Assembly Building to Kennedy Space Center's launch pad 39A for the ship's final flight before retirement.

NASA says technicians are repairing a minor hydraulic leak on a corner valve for the crawler-transporter's jacking and leveling system.

You are watching live streaming video from Kennedy Space Center where Atlantis should start rolling out shortly. The move has been delayed a bit.

The gate just outside the VAB on the crawlerway is being opened now to let Atlantis out.

The mobile launch platform has been jacked to travel height for leaving the Vehicle Assembly Building. First motion of rollout expected very shortly.

The crawler-transporter is literally picking up the space shuttle's launch platform now. The crawler is performing the hydraulic lift from the Vehicle Assembly Building pedestals.

A massive crowd is building here at the Kennedy Space Center to witness tonight's final rollout of a space shuttle vehicle. Workers and their families are gathering along the crawlerway to watch Atlantis emerge from the Vehicle Assembly Building.

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The crawler has propelled itself into place beneath shuttle Endeavour's mobile launch platform. Later in the preparations, the crawler's hydraulics will lift the shuttle platform off the VAB pedestals.

The crew for the crawler-transporter, which was parked just outside, has gotten the giant machine fired up and ready for tonight's operations. The crawler is driving into the Vehicle Assembly Building now to pick up the shuttle for this heavy-lifting move to the pad.

It is call-to-stations time for the rollout team. The various members started reporting for duty at 3:45 p.m. to begin the final four hours of preparations leading to tonight's planned 8 p.m. EDT first motion of the space shuttle rollout.

The weather forecast for tonight's move of the space shuttle Atlantis is looking great. Meteorologists are predicting no chance of violating the wind or lightning rules that would prohibit rolling out the spacecraft.

While space shuttle Endeavour completes her final orbits of the planet tonight, sistership Atlantis will be traveling to Kennedy Space Center's launch pad 39A beginning at 8 p.m. EDT.

The ground team responsible for moving the spacecraft along the 3.5-mile stone-covered roadway from the Vehicle Assembly Building to the seaside pad is scheduled to report for duty at 4 p.m.

The crawler-transporter will hydraulically lift the mobile launching platform and carry the shuttle on the six-hour trip. If all goes according to plan, Atlantis should be secured atop the pad and the pad swing arms extended long before dawn.

Watch this page for live streaming video coverage!

NASA today set Friday, July 8 as the official target launch date for the final space shuttle mission. Liftoff of Atlantis is scheduled for 11:38 a.m. EDT to begin the 12-day voyage to deliver equipment and supplies to the International Space Station.

Inside the Vehicle Assembly Building, workers today attached Atlantis to the external tank and set of solid rocket boosters. An initial "soft" connection was made before the orbiter was firmly secured in place.

Umbilicals are being mated between the shuttle and its mobile launching platform. The standard shuttle interface testing will begin on Tuesday.

Atlantis has begun its careful descent to meet up with the external fuel tank and twin solid rocket boosters that are stacked and waiting a mobile launching platform.

A photo posted on our Facebook page shows Atlantis suspended above the external tank and solid rockets while technicians fine-tune the alignment.

A photo posted on our Facebook page shows Atlantis suspended above the external tank and solid rockets while technicians fine-tune the alignment.

We're now awaiting Atlantis to slide down into position next to the external fuel tank.

The orbiter is crossing the transom into the assembly bay.

Atlantis is headed upward inside the VAB en route to a room next door, where the shuttle's fuel tank and solid rocket boosters are stacked atop a mobile launch platform.

The orbiter has been canted at a 45-degree angle to be put in the proper orientation to be lifted into the upper reaches of the Vehicle Assembly Building.

Our latest photo gallery shows Atlantis hanging on a crane inside mammoth assembly building for the final time.

A detailed photographic survey of Atlantis' heat shield is underway. This baseline imagery is being collected before the orbiter is transferred into the assembly bay later today.

Atlantis is beginning to go vertical! The Vehicle Assembly Building cranes have started to turn the spacecraft upright to point her nose toward the sky.

The Orbiter Transporter System that hauled Atlantis between the hangar and VAB yesterday has done its job and driven away. This clears the center aisle of the assembly building for rotation of the shuttle from horizontal to vertical.

Atlantis is being removed from the 76-wheel orbiter transporter inside the Vehicle Assembly Building transfer aisle. The methodical, multi-hour process will first lift the vehicle above the transporter, then pivot Atlantis vertical.

After achieving the proper alignment, the massive crane will hoist Atlantis high into the mammoth 52-story building and into the adjacent high bay where the shuttle's tank and boosters await. Finally, the crane then lowers the orbiter into place for bolting to the external tank.

The "sling" has been bolted in four locations to Atlantis. The shuttle will be lifting off the transporter soon.

Check out some pictures taken this morning of the attachment work.

Right now in the Vehicle Assembly Building, the metal "sling" is being positioned to capture Atlantis this morning. It will lift the shuttle from the hauler that carried spacecraft from the hangar.

That heavy-duty crane will rotate Atlantis vertically later today, then begin the methodical process of hoisting the ship high into the rafters, over to the assembly bay and carefully lowering Atlantis into position next to the awaiting fuel tank for attachment.

The transporter is rolling to a stop in the center aisle of the VAB. The final "rollover" of the space shuttle program is complete.

Atlantis is crossing the threshold into the Vehice Asembly Building where its external fuel tank and twin solid rockets await atop a mobile launching platform for the orbiter's attachment.

The shuttle's quarter-mile road trip has resumed at the Kennedy Space Center after letting workers get some up close and personal pictures of the spaceship. Even the flight's four astronauts -- commander Chris Ferguson, pilot Doug Hurley and mission specialists Rex Walheim and Sandy Magnus -- traveled from Houston to attend today's event and mingle with the large crowd.

Ground crews are getting back into position to finish moving Atlantis.

Atlantis has stopped on the roadway between the hangar and Vehicle Assembly Building for employees to take pictures and celebrate the space shuttle. The move will continue a few hours from now.

In our live video stream, you are hearing the Endeavour mission audio while watching Atlantis.

The Orbiter Processing Facility team has come outside to pose for a group picture with Atlantis.

The spacecraft has emerged into the bright sun of this Florida morning, almost 24 hours since sistership Endeavour's blastoff from the spaceport.

You can follow Endeavour's progress in our separate Mission Status Center.

Atlantis' tail is sticking outside the hangar now.

The Orbiter Transporter System is doing the heavy-duty work during today's move. Originally designed and built for use at Vandenberg Air Force Base in California, the transporter was brought to Kennedy Space Center in 1989 after the West Coast space shuttle launch site was mothballed.

The transporter is 106 feet in length, weighs 167,000 pounds unloaded and about 327,000 pounds with an orbiter on top and sports 76 wheels. It has a turning radius of 66 feet.

You can envision the OTS as a yellow motorized trailer. At Vandenberg, shuttles were supposed to be prepared for flight in a hangar on the military installation's north side, then ferried aboard the OTS transporter about 17 miles across the hilly terrain to the Space Launch Complex-6 pad on South Base.

In contrast, shuttles in the program's early years at KSC were towed between the hangars and Vehicle Assembly Building with the orbiters' landing gear down.

But with Vandenberg's shuttle plans cancelled after Challenger, the transporter was brought to Florida and pressed into service. It allows NASA to retract a shuttle's landing gear and seal the critical heat-protection tiles around the doors while still in the hangar before rolling out.

The top speed of the transporter while hauling Endeavour to the Vehicle Assembly Building is five miles per hour. The V12 engine generates about 335 horsepower.

ROLL BEGINS. Atlantis has begun to slowly back out of the hangar, bound for its stopover at the Vehicle Assembly Building in preparation for the final space shuttle mission.

This initial part of the move occurs at a snail's pace given the close quarters between Atlantis and the cocoon-like scaffolding inside the hangar that enclosed the ship. Once outside, the motorized transporter will throttle up to a casual walking pace and head for parking spot for employees to take pictures of the spaceship today.

Arrival in the VAB is targeted for 2 p.m. EDT.

It's moving day for Atlantis as the space shuttle travels from the Orbiter Processing Facility bay No. 1 to the Vehicle Assembly Building.

Mounted atop a 76-wheel transporter, the Atlantis will be backed out of the space-age garage and then go on display for several hours outdoors

Technicians inside the VAB will hoist the spaceplane upright and attach it to the external fuel tank and solid rocket boosters.

While space shuttle Endeavour takes center stage with her planned blastoff Monday, sistership Atlantis is waiting in the wings to fly the program's final mission sometime in mid-July.

Delays getting Endeavour launched on the penultimate voyage has created a ripple effect in the schedule and bumped Atlantis from her original June 28 target liftoff date.

Atlantis has been readied inside the Kennedy Space Center's processing facility No. 1 over the past year for this STS-135 mission. To finish up the hangar activities, technicians weighed the ship and made center of gravity determinations on May 5, mounted the vehicle aboard the motorized transport trailer on May 6 and finished retracting the landing gear on May 9.

The next event is moving Atlantis to the nearby Vehicle Assembly Building for mating to the external fuel tank and twin solid rocket boosters. That trip has been placed on hold until Endeavour is successfully launched.

Under the latest schedule assuming Endeavour flies Monday, Atlantis will be rolled to the VAB on Tuesday morning starting at 8 a.m. EDT.

Teams will get the ship inside the cavernous building and prepared to go vertical during that day's primary work shift. The actual hoisting of the spaceplane and attaching it to the tank occurs the following day.

Rollout of the fully assembled space shuttle to launch pad 39A is slated to begin May 31 at 8 p.m. EDT. The overnight trip takes about 7 hours to complete.

Ironically, Endeavour should be flying home that night for a planned 2:32 a.m. touchdown at the Kennedy Space Center's runway just a few miles away from the pathway where Atlantis would be traversing to the launch pad.

"We've looked very hard at our workforce and there is different people to take care of the landing and the rollout, just completely different work crews," shuttle launch director Mike Leinbach says.

"So if it does happen that way, it will be a very, very special night. We'll be rolling out to the pad...and then here comes Endeavour back to KSC. It will be a nice night to witness and be part of."

The exact launch date for Atlantis is under review. Officials are looking at the second week of July, but they want to wait until Endeavour gets off the pad before finalizing Atlantis' schedules.

The external fuel tank for space shuttle Atlantis' flight this summer was hoisted from the checkout cell over to the integration bay inside the Vehicle Assembly Building today. The tank was positioned between the twin solid rocket boosters just after 2 p.m. this afternoon.

Revised plans have accelerated the trip by Atlantis from the hangar to the VAB for mating to the tank and boosters. That has been moved up by two days to May 10. However, the rest of the mission schedule remains the same.

The space shuttle Atlantis' payload bay doors were closed and locked today in preparation for moving the orbiter from the hangar to the Vehicle Assembly Building in early May.

Preflight work inside Orbiter Processing Facility bay 1 is nearing completion to ready the ship for the final flight of the space shuttle program this summer.

And with the twin solid rocket boosters now stacked atop the mobile launching platform, the external fuel tank remains on schedule for attachment next Monday.

The four-person crew continues its hectic training in Houston for the STS-135 mission. According to mission specialist Sandy Magnus' tweets this week, the astronauts have conducted a Flight Day 4 simulation for installing the Raffaello cargo module to the International Space Station, run through a rendezvous rehearsal and practiced the Picosat deployment planned the day before landing.

Commander Chris Ferguson tweeted that his crew plans to attend Atlantis' move to the VAB and the subsequent rollout of the space shuttle to launch pad 39A.

Meanwhile, the U.S. government budget approved last week all but validates NASA's hope to fly Atlantis on this bonus mission as soon as June 28, according to agency officials. Read our full story.

The past week saw the upper solid-fuel motor segments attached and the nose caps set in place atop the final space shuttle rocket boosters, completing the last buildup in the program's three-decade history.

Read our full story.

The powerful booster rockets for the final space shuttle launch continue to be stacked segment-by-segment inside the Vehicle Assembly Building in preparation to propel Atlantis skyward this summer.

Read our full story.

The space shuttle Atlantis astronauts visited Kennedy Space Center on Thursday and Friday for up-close and personal interaction with the orbiter and the payloads being readied for flight this summer.

Read our full story.

The last-ever set of space shuttle solid-fuel rockets began taking shape Tuesday evening as technicians started stacking the boosters that will power Atlantis this summer.

Read our full story.