Astronauts Philippe Perrin and Franklin Chang-Diaz have emerged from the International Space Station's Quest airlock to begin the mission's third and final spacewalk - a planned 7 hour excursion to replace the faulty wrist-roll joint on the station’s Canadarm2 robotic arm. The spacewalk, or EVA, officially started at 11:16 a.m. EDT when the astronauts switched to internal battery power in their spacesuits.

The spacewalkers will first remove the Canadarm2's 'hand', the latching end effector (LEE), exposing the faulty wrist roll joint. They will then disconnect the faulty joint and carry it to Endeavour’s payload bay for storage. Chang-Diaz, wearing the spacesuit with the red stripe, will remove the new wrist-roll joint from its carrier in the payload bay, Perrin will move it up to the Canadarm2 and the pair will then install and test the new joint.

Expedition 5 flight engineers Peggy Whitson and Valeri Korzun will spend part of the day transferring the last of the unneeded equipment and trash into the Leonardo Multi-Purpose Logistics Module to be returned to Earth with Endeavour.

Astronauts Philippe Perrin and Franklin Chang-Diaz are working outside the International Space Station on the mission's third and final spacewalk - a planned 7 hour excursion to replace the faulty wrist-roll joint on the station’s Canadarm2 robotic arm.

After a delay due to static in the space-to-ground communications loop (likely due to water dripping from a drink bag inside Chang-Diaz' helmet), the spacewalk, or EVA, officially started at 11:16 a.m. EDT when the astronauts switched to internal battery power in their spacesuits. That delay, plus additional time spent in the EVA set-up chores, has the spacewalk running over an hour behind the timeline at this point.

The spacewalkers have unwrapped thermal blankets covering the Canadarm2's 'hand' - the latching end effector (LEE) - and removed the LEE, exposing the faulty wrist roll joint. They will soon disconnect the faulty joint and carry it to Endeavour’s payload bay for storage. Chang-Diaz, wearing the spacesuit with the red stripe, will remove the new wrist-roll joint from its carrier in the payload bay, Perrin will move it up to the Canadarm2 and the pair will then install and test the new joint.

Expedition 5 flight engineers Peggy Whitson and Valeri Korzun will spend part of the day transferring the last of the unneeded equipment and trash into the Leonardo Multi-Purpose Logistics Module to be returned to Earth with Endeavour.

Astronauts Philippe Perrin and Franklin Chang-Diaz have made up over an hour on their timeline during today's spacewalk outside the International Space Station - the mission's third and final EVA. The planned 7-hour excursion to replace the faulty wrist-roll joint on the station’s Canadarm2 robotic arm was running close to 1 1/2 hours behind schedule but the two astronauts have recouped all of that time and are on-schedule at this point.

The spacewalkers unwarpped thermal blankets covering the Canadarm2's 'hand' - the latching end effector (LEE) - then removed the LEE, exposing the faulty wrist roll joint. Then, they disconnected the faulty joint and carried it to Endeavour’s payload bay for storage. Chang-Diaz, wearing the spacesuit with the red stripe, removed the new wrist-roll joint from its carrier in the payload bay, while Perrin moved it up to the Canadarm2. The pair successfully installed the new joint and ground controllers have again powered-up the Canadarm2. Extensive checkout of the robotic arm and its new joint will be performed by the robotics officer in Mission Control.

Today's spacewalk, or EVA, officially started at 11:16 a.m. EDT when the astronauts switched to internal battery power in their spacesuits. After a delay due to static in the space-to-ground communications loop (likely due to water dripping from a drink bag inside Chang-Diaz' helmet).

Expedition 5 flight engineers Peggy Whitson and Valeri Korzun will spend part of the day transferring the last of the unneeded equipment and trash into the Leonardo Multi-Purpose Logistics Module to be returned to Earth with Endeavour.

Astronauts Philippe Perrin and Franklin Chang-Diaz have successfully replaced a faulty wrist-roll joint in the International Space Station's robotic arm during a 7 hour, 17 minute spacewalk - the mission's third and final EVA - and have now reentered the station's Quest airlock.

Today's spacewalk, or EVA, officially started at 11:16 a.m. EDT after a delay due to static in the space-to-ground communications loop (likely due to water dripping from a drink bag inside Chang-Diaz' helmet) and concluded at 6:33 p.m. EDT.

The spacewalkers began by unwrapping thermal blankets covering the Canadarm2's 'hand' - the latching end effector (LEE) - then removed the LEE, exposing the faulty wrist roll joint. Then, they disconnected the faulty joint and carried it to Endeavour’s payload bay for storage. Chang-Diaz removed the new wrist-roll joint from its carrier in the payload bay, while Perrin moved it up to the Canadarm2.

The pair successfully installed the new joint and ground controllers have again powered-up the Canadarm2. Extensive checkout of the robotic arm and its new joint will be performed by the robotics officer in Mission Control and the early indications are that the joint is performing as expected.

Expedition 5 flight engineers Peggy Whitson and Valeri Korzun also spend part of the day transferring the last of the unneeded equipment and trash into the Leonardo Multi-Purpose Logistics Module to be returned to Earth with Endeavour.

Astronauts Philippe Perrin and Franklin Chang-Diaz successfully replaced a faulty wrist-roll joint in the International Space Station's Canadarm2 robotic arm during a 7 hour, 17 minute spacewalk on Thursday, restoring the arm to full functionality.

Thursday's spacewalk - the third and final EVA of the mission - started at 11:16 a.m. EDT after a delay due to static in the space-to-ground communications loop (likely due to water dripping from a drink bag inside Chang-Diaz' helmet) and concluded at 6:33 p.m. EDT.

The spacewalkers began by unwrapping thermal blankets covering the Canadarm2's 'hand' - the latching end effector (LEE) - then removed the LEE, exposing the faulty wrist roll joint. Then, they disconnected the faulty joint and carried it to Endeavour’s payload bay for storage. Chang-Diaz removed the new wrist-roll joint from its carrier in the payload bay, while Perrin moved it up to the Canadarm2.

The pair successfully installed the new joint and ground controllers powered-up the newly-restored Canadarm2. The robotic arm was declared to be fully operational following an extensive checkout by the robotics officer in Mission Control and crew members Dan Bursch and Valeri Korzun.

Expedition 5 flight engineers Peggy Whitson and Valeri Korzun also spend part of the Thursday transferring the last of the unneeded equipment and trash into the Leonardo Multi-Purpose Logistics Module to be returned to Earth with Endeavour.

Shuttle Endeavour’s astronauts were awakened around 5:30 a.m. EDT to the strains of the U.S. National Anthem, played in honor of Flag Day in the United States.

Assisted by the ISS Expedition 5 crew, Endeavour astronauts will deactivate the Leonardo Multi-Purpose Logistics Module (MPLM) and commander Ken Cockrell will grapple the MPLM with the shuttle's robotic arm. Cockrell will stow the MPLM in Endeavour's cargo bay for Monday's scheduled return to Earth with 4,665 pounds of discarded equipment, supplies and trash.

Following Thursday's successful spacewalk by Franklin Chang-Diaz and Phillippe Perrin to replace a faulty wrist-roll joint on the International Space Station's Canadarm2 robotic arm, engineers failed in an attempt to provide power to the Canadarm2. Engineers believe that a minor software glitch is responsible and are confident that the robotic arm will be fully functional before the Canadarm2 'walks off' to position itself on the station's Mobile Transporter and MPLM base.

Endeavour commander Ken Cockrell and Paul Lockhart will also fire the orbiter's steering jets to raise the space station's altitude once more before the shuttle undocks from the orbital complex tomorrow.

The Italian-built "moving van" known as Leonardo is all packed up with nearly 4,700 pounds of trash and unneeded equipment, and is ready for shipment back to the Kennedy Space Center.

The module is shut down and its hatch to the Unity node is closed. The next step is for the shuttle's robot arm to be powered up and used to grab hold of the module. That is expected to take place within the hour.

Hooks and latches securely fastening Leonardo to Unity will be released and at 2:48 p.m. EDT the robot arm is to begin moving the module down toward the cargo bay, berthing the cylinder about 4:15 p.m. EDT.

The robot arm will then release the module, be parked for the return home and ordered powered down during the next 15 minutes or so.

French space agency astronaut Philippe Perrin is expected to be the principal shuttle robot arm operator today, with Endeavour commander Ken Cockrell backing him up.

Leonardo, the Italian-built moving van, is safely latched back inside the space shuttle Endeavour's cargo bay.

French astronaut Philippe Perrin operated the shuttle's robot arm to pluck Leonardo from the side of the Unity node on the International Space Station and transfer the container down to the payload bay.

Mission Control in Houston confirmed the module was secure in the bay at 4:12 p.m. EDT.

Meanwhile, engineers think the trouble they are having powering up the station's robot arm from the newly attached Mobile Base System is just a software glitch and should be easily fixed.

The Canadarm2 itself, including its new wrist roll joint that was installed during a spacewalk on Thursday, is working fine.

The crew of shuttle Endeavour, including the returning ISS Expedition 4 team, will say good-bye to the Internation Space Station and the Expedition 5 crew early on Saturday morning.

The closing of hatches between orbiter and station is scheduled for about 7:30 a.m. EDT. About three hours later, at 10:32 a.m. EDT, Endeavour will undock from the orbiting complex.

On Friday, Leonardo, the Italian-built moving van, was safely latched back inside the space shuttle Endeavour's cargo bay.

French astronaut Philippe Perrin operated the shuttle's robot arm to pluck Leonardo from the side of the Unity node on the International Space Station and transfer the container down to the payload bay.

Mission Control in Houston confirmed the module was secure in the bay at 4:12 p.m. EDT.

Meanwhile, engineers think the trouble they are having powering up the station's robot arm from the newly attached Mobile Base System is just a software glitch and should be easily fixed.

The Canadarm2 itself, including its new wrist roll joint that was installed during a spacewalk on Thursday, is working fine.

Their mission accomplished, the crew of shuttle Endeavour, including the three returning members of ISS Expedition 4, have said their goodbyes to the new Expedition Five crew and closed the hatches between the orbiter and the International Space Station.

Undocking is scheduled for 10:32 a.m. EDT as the two spacecraft fly over western Kazakhstan.

Endeavour will be pushed free of the orbital complex by springs in the station's docking system, then commander Ken Cockrell and pilot Paul Lockhart will fire the shuttle's steering jets to pull away from the outpost.

Once the two spacecraft are separated by about 450 feet, Lockhart will maneuver Endeavour to perform a one-hour, 1 1/4 lap flyaround of the space station at about 12:16 p.m. EDT. Endeavour is scheduled to land at the Kennedy Space Center on Monday, weather permitting.

Endeavour's crew was awakened this morning at about 4:40 a.m. EDT to the sounds of "Hello to All the Children of the World," performed by Paul Lockhart's son and classmates.

Shuttle Endeavour pilot Paul Lockhart fired the spaceplane's thrusters at 12:15 p.m. EDT to clear the vehicle away from the International Space Station.

The maneuver sets up the shuttle for its two-day journey home to a landing at the Kennedy Space Center in Florida on Monday.

Undocking took place at 10:32 a.m. EDT, with Lockhart flying Endeavour away to a distance of 450 feet. He then flew the shuttle around the station, resulting in some breathtaking pictures of station Alpha and the planet Earth being beamed down to the ground on NASA TV.

After executing the separation maneuver there was one more round of well wishing and farewells between the seven humans aboard Endeavour and the three crewmembers inside Alpha.

"Alpha we wish you a very wonderful flight. We've completed our separation burn. We're heading home," said Endeavour commander Ken Cockrell.

"OK, thanks for the ride," replied Expedition Five flight engineer Peggy Whitson.

It is expected to be a relatively quiet day for both crews the rest of today.

An eight-day stay at the International Space Station by shuttle Endeavour concluded at 10:32 a.m. EDT as the shuttle pulled away from the outpost.

Undocking took place as the two ships circled the Earth high above Kazakhstan, just west of the Baikonur Cosmodrome.

Pilot Paul Lockhart is at the controls now and plans to fly the orbiter around the station during the next hour or so before firing jets to clear the shuttle away from the area.

The victory lap will allow the shuttle's occupants to inspect the station and photograph the outpost so engineers on the ground can study the images to learn how the orbiting complex is handling its long duration stay in space.

Left aboard the station is the new Expedition Five crew of Valery Korzun, Peggy Whitson and Sergei Treschev, while now a part of Endeavour's crew is the Expedition Four team of Yuri Onufrienko, Dan Bursch and Carl Walz.

The Expedition Four crew's return to Earth is scheduled for Monday. Endeavour is to touch down at the Kennedy Space Center at 1 p.m. EDT.

The crew of shuttle Endeavour will spend their last full day in space Sunday preparing the orbiter for Monday's re-entry and return to Earth.

Commander Ken Cockrell, pilot Paul Lockhart and mission specialist Franklin Chang-Diaz will check out the shuttle's reaction control system and flight control surfaces required for Endeavour's long fiery plunge through the atmosphere. The orbiter is scheduled to land at the Kennedy Space Center at 12:59 p.m. EDT Monday and the weather outlook is favorable for the first landing opportunity.

Returning ISS Expedition 4 crew members Yuri Onufrienko, Carl Walz and Dan Bursch, assisted by Endeavour mission specialist Phillippe Perrin will install their re-entry seats on shuttle's middeck.

The astronauts were awakened this morning at 4:23 a.m. EDT to the sounds of "Where My Heart Will Take Me," the theme song from Star Trek: Enterprise, performed by Russell Watson

Mother Nature holds the cards for Monday's scheduled 12:59 p.m. EDT landing of shuttle Endeavour after a mission to the International Space Station.

Weather forecasts, which looked promising at week's end, are now indicating the likelihood of clouds and rain showers in the vicinity of the Kennedy Space Center's Shuttle Landing Facility and its three-mile long runway for Monday's first landing opportunity. A threat of thunderstorms is added for the second landing opportunity.

The backup landing site at Edwards AFB, California will not be activated on Monday. Endeavour has sufficient consumables onboard to remain in orbit until Thursday, if necessary.

Endeavour's crew, including the three returning members of ISS Expedition 4, spent part of Sunday preparing the orbiter for its return, then enjoyed a few hours of free time.

Rainy weather may delay today's scheduled return of shuttle Endeavour and its seven member crew, including the three returning members of ISS Expedition 4, to the Kennedy Space Center's Shuttle Landing Facility. Endeavour has two Florida landing opportunities available today at 12:59 p.m. EDT and 2:36 p.m. EDT.

The Spaceflight Meteorology Group's landing forecast issued at 7 a.m. EDT indicates that conditions near the shuttle's 3-mile long runway will likely violate a number of weather constraints - rain showers and thunderstorms within 30 miles of the runway, cloud cover that will obscure visibility, precipitation and crosswinds in excess of limits. Any one of these conditions is sufficient to 'wave off' a landing attempt.

The first indication of a potential delay will occur around 9:10 a.m. EDT when Mission Control is scheduled to call for the orbiter's payload bay doors to be closed in preparation for re-entry - if that call is not made, a wave off is likely. The timeline for a landing on today's first opportunity calls for the 'Go for de-orbit burn' decision to be made at 11:30 a.m. EDT, followed by the de-orbit burn at 11:51 a.m. EDT.

The backup landing site at Edwards AFB, California will not be activated on Monday. Endeavour has sufficient consumables onboard to remain in orbit until Thursday, if necessary.

The seven astronauts and cosmonauts were awakened at 4:23 a.m. EDT to the sounds of "The Eyes of Texas," performed by the University of Texas Marching Band for commander Ken Cockrell and pilot Paul Lockhart who both hold degrees from that university.

Shuttle Endeavour's payload bay doors have been closed and latched in preparation for a fiery plunge through Earth's atmosphere and a long, gliding descent to the Kennedy Space Center's Shuttle Landing Facility. Florida's dynamic and unpredictable weather, however, threatens to delay the homecoming.

Two Florida landing opportunities are available today at 12:59 p.m. EDT and 2:36 p.m. EDT, but rainy weather and clouds may conspire to postpone the return of the shuttle and its seven member crew, including the three returning members of ISS Expedition 4.

The Spaceflight Meteorology Group's landing forecast issued at 7 a.m. EDT indicates that weather conditions near the shuttle's 3-mile long runway will likely violate a number of end-of-mission constraints - rain showers and thunderstorms within 30 miles of the runway, cloud cover that will obscure visibility, precipitation and crosswinds in excess of limits. Any one of these conditions is sufficient to 'wave off' a landing attempt.

Flight controllers are hoping for a brief gap between two converging weather systems - one approaching from the north, the other from the south - will provide a slim window of opportunity to bring Endeavour home to Florida.

The timeline for a landing on today's first opportunity calls for the 'Go for de-orbit burn' decision to be made at 11:30 a.m. EDT, followed by the de-orbit burn at 11:51 a.m. EDT, resulting in a 12:59 p.m. EDT touchdown.

The backup landing site at Edwards AFB, California will not be activated on Monday. Endeavour has sufficient consumables onboard to remain in orbit until Thursday, if necessary.

The seven astronauts and cosmonauts were awakened at 4:23 a.m. EDT to the sounds of "The Eyes of Texas," performed by the University of Texas Marching Band for commander Ken Cockrell and pilot Paul Lockhart who both hold degrees from that university.

Florida's dynamic weather will likely keep shuttle Endeavour in orbit for another day.

Mission Control has advised the crew to delay the so-called fluid loading protocol - the consumption of fluid by the astronauts to properly condition their bodies for a return from weightlessness. This is a clear indication that the landing will not be attempted, at least on the first landing opportunity.

Two weather fronts with convective activity are converging on the Kennedy Space Center from the northwest and southwest - rain showers within 30 miles of the Shuttle Landing Facility have been reported and the forecast calls for the formation of thunderstorms with the potential for hail throughout the afternoon.

Endeavour's payload bay doors remain closed and latched in preparation for a fiery plunge through Earth's atmosphere, but the mission commentator just stated that the chances are slim that the orbiter will return today.

Two Florida landing opportunities are available today at 12:59 p.m. EDT and 2:36 p.m. EDT for the return of the shuttle and its seven member crew, including the three returning members of ISS Expedition 4.

The Spaceflight Meteorology Group's landing forecast indicates that weather conditions near the shuttle's 3-mile long runway will violate a number of end-of-mission constraints - rain showers and thunderstorms within 30 miles of the runway, cloud cover that will obscure visibility, precipitation and crosswinds in excess of limits. Any one of these conditions is sufficient to 'wave off' a landing attempt.

The next crucial event in the timeline for a landing on today's first opportunity is the 'Go for de-orbit burn' decision to be made at 11:30 a.m. EDT. If so ordered, the de-orbit burn would take place at 11:51 a.m. EDT, resulting in a 12:59 p.m. EDT touchdown.

Florida's dynamic weather will likely keep shuttle Endeavour in orbit for another day.

Mission Control has just waved-off today's first landing opporunity after advising the crew to delay the so-called fluid loading protocol - the consumption of fluid by the astronauts to properly condition their bodies for a return from weightless. This is a clear indication that the landing will not be attempted, unless weather conditions dramatically improve.

Two weather fronts with convective activivty are converging on the Kennedy Space Center from the northwest and southwest - rain showers within 30 miles of the Shuttle Landing Facility have been reported and the forecast calls for the formation of thunderstorms with the potential for hail throughout the afternoon.

A second Florida landing opportunity is available today at 2:36 p.m. EDT for the return of the shuttle and its seven member crew, including the three returning members of ISS Expedition 4.

The Spaceflight Meteorology Group's landing forecast predicts weather conditions near the shuttle's 3-mile long runway will violate a number of end-of-mission constraints - rain showers and thunderstorms within 30 miles of the runway, cloud cover that will obscure visibility, precipitation and crosswinds in excess of limits. Any one of these conditions is sufficient to 'wave off' the second landing attempt.

The next crucial event in the timeline for a landing on today's second opportunity is the 'Go for de-orbit burn' decision to be made at about 1:10 p.m. EDT. If so ordered, the de-orbit burn would take place at 1:30 p.m. EDT, resulting in a 2:36 p.m. EDT touchdown.

Florida's dynamic weather will keep shuttle Endeavour in orbit for at least one more day.

Mission Control has just waved-off both of today's landing opportunities after it became obvious that the deteriorating weather conditions would not support a landing.

Two Florida landing opportunities are available on Tuesday at 11:56 a.m. EDT and 1:32 p.m. EDT for the homecoming of the shuttle and its seven member crew, including the three returning members of ISS Expedition 4.

The backup landing site at Edwards AFB, California was not activated on Monday and officials will decide later today if it will be activated on Tuesday. Endeavour has sufficient consumables onboard to remain in orbit until Thursday, if necessary.

Bad weather may keep shuttle Endeavour in orbit until Wednesday as conditions at landing strips on both coasts do not look promising for Tuesday.

Thunderstorms and rain showers forced NASA officials to postpone both of today's landing opportunities, delaying for the homecoming of the shuttle and its seven member crew, including the three returning members of ISS Expedition 4 who will extend their U.S. space endurance record to at least 195 days in orbit.

Endeavour has two Florida landing opportunities are available on Tuesday at 11:56 a.m. EDT and 1:32 p.m. EDT, but meteorologists are predicting conditions similar to today and the weather conditions at the Kennedy Space Center are forecast to be 'No-Go' for both landing opportunities.

The backup landing site at Edwards AFB, California was not activated on Monday, but officials will activate it on Tuesday, although conditions at Edwards are also forecast 'No Go' due to crosswinds out of limits. Endeavour has sufficient consumables onboard to remain in orbit until Thursday, if necessary.

Rain and thunderstorms are again forecast for Florida's Space Coast on Tuesday, while stiff crosswinds are predicted at Edwards AFB, California - a combination that threatens to keep shuttle Endeavour in orbit until Wednesday.

Thunderstorms and rain showers forced NASA officials to postpone both of Monday's Florida landing opportunities, delaying the homecoming of the shuttle and its seven member crew, including the three returning members of ISS Expedition 4 who will extend their U.S. space endurance record to at least 195 days in orbit.

Endeavour has two Florida landing opportunities are available on Tuesday at 11:55 a.m. and 1:31 p.m. EDT, but meteorologists are again predicting rain showers and thunderstorms within 30 miles of the Kennedy Space Center - 'No-Go' conditions for both landing opportunities.

The backup landing site at Edwards AFB, California was not activated on Monday, but officials will activate it on Tuesday, although conditions at Edwards are also forecast to be 'No Go' due to crosswinds out of limits. The two Edwards opportunities will be at 3:00 p.m. and 4:36 p.m. EDT, but mission managers will consider a Tuesday landing in the Mojave desert only if poor weather is forecast on both coasts on Wednesday.

Endeavour has sufficient consumables onboard to remain in orbit until Thursday, if necessary.

Clouds, rain showers and thunderstorms may again postpone today's scheduled return of shuttle Endeavour and its seven member crew, including the three returning members of ISS Expedition 4, to the Kennedy Space Center's Shuttle Landing Facility. Endeavour has two Florida landing opportunities available today at 11:55 a.m. and 1:31 p.m. EDT.

The Spaceflight Meteorology Group's landing forecast issued at 6 a.m. EDT indicates that conditions near the shuttle's 3-mile long runway will likely violate a number of weather constraints - rain showers and thunderstorms within 30 miles of the runway, cloud cover that may obscure visibility and precipitation. Any one of these conditions is sufficient to 'wave off' a landing attempt.

The timeline for a landing on today's first opportunity calls for the 'Go for de-orbit burn' decision to be made at about 10:25 a.m. EDT, followed by the de-orbit burn at 10:47 a.m. EDT. The second landing opportunity would require a de-orbit burn at 12:24 p.m. EDT, resulting in a 1:31 p.m. EDT landing.

Weather on the West Coast isn't promising either. Stiff crosswinds are predicted at the backup landing site at Edwards AFB, California for one of today's two potential landing opportunities. The two Edwards opportunities will be at 3:01 p.m. and 4:37 p.m. EDT, but mission managers will consider landing in the Mojave desert today only if poor weather is again forecast on both coasts on Wednesday.

Endeavour has sufficient consumables onboard to remain in orbit until Thursday, if necessary.

The seven astronauts and cosmonauts were awakened at about 3:30 a.m. EDT to the sounds of "Sojourner" by Matt Gast, the flight's lead timeliner or scheduler of crew activities.

Clouds, rain showers and thunderstorms will likely postpone today's scheduled return of shuttle Endeavour and its seven member crew, including the three returning members of ISS Expedition 4, to the Kennedy Space Center's Shuttle Landing Facility. Endeavour has two Florida landing opportunities available today at 11:55 a.m. and 1:31 p.m. EDT.

The Shuttle Training Aircraft piloted by astronaut Kent Rominger is observing mostly overcast skies over Central Florida. The Spaceflight Meteorology Group's landing forecast issued at 6 a.m. EDT indicates that conditions near the shuttle's 3-mile long runway will likely violate a number of weather constraints - rain showers and thunderstorms within 30 miles of the runway, cloud cover that may obscure visibility and precipitation. Any one of these conditions is sufficient to 'wave off' a landing attempt.

The timeline for a landing on today's first opportunity calls for the 'Go for de-orbit burn' decision to be made at about 10:25 a.m. EDT, followed by the de-orbit burn at 10:47 a.m. EDT. The second landing opportunity would require a de-orbit burn at 12:24 p.m. EDT, resulting in a 1:31 p.m. EDT landing.

Mission Control just informed the crew that they will not attempt a landing at the Edwards AFB, California backup site today. Weather in Florida is expected to improve on Wednesday, and also looks favorable at Edwards which will have three landing opportunities available.

Endeavour has sufficient consumables onboard to remain in orbit until Thursday, if necessary.

Bad weather - thunderstorms and convective activity with anvil clouds to the southwest of the Kennedy Space Center - has forced controller to wave-off the first of two landing opportunities for shuttle Endeavour.

Controllers will closely monitor the weather in the slim chance that conditions will improve for today's second Florida landing opportunity at 1:31 p.m. EDT. The de-orbit burn to commit to the second opportunity would be at 12:24 p.m. EDT

Looking at improved weather forecasts for Wednesday on both coasts, NASA decided against a landing attempt at the backup site at Edwards AFB, California, hoping that the Florida weather would improve sufficiently for one last attempt tomorrow.

There are five landing opportunities available on Wednesday for Endeavour - two at the Kennedy Space Center and three at Edwards AFB. The Florida opportunities will be at 10:52 a.m. and 12:28 p.m. EDT, while the three Edwards AFB opportunities will be at 1:58 p.m., 3:34 p.m. and 5:10 p.m. EDT.

Weather at the Kennedy Space Center is forecast to be marginal on Wednesday, with a chance of rain showers within 30 miles of the Shuttle Landing Facility. Weather at Edwards AFB, however, is predicted to be ideal for all three landing opportunities, although NASA needs to land Endeavour in Florida to have any hope of maintaining its current flight schedule for late this year.

Bad weather - thunderstorms and convective activity with anvil clouds to the southwest of the Kennedy Space Center - has forced flight controllers to wave-off the first of two landing opportunities for shuttle Endeavour.

Controllers will closely monitor the weather in the slim chance that conditions will improve for today's second Florida landing opportunity at 1:31 p.m. EDT. The de-orbit burn to commit to the second landing opportunity would be at 12:24 p.m. EDT

Looking at improved weather forecasts for Wednesday on both coasts, NASA decided against a landing attempt at the backup site at Edwards AFB, California, hoping that the Florida weather would improve sufficiently for one last attempt tomorrow in the likely event that the shuttle cannot land today.

There are five landing opportunities available on Wednesday for Endeavour - two at the Kennedy Space Center and three at Edwards AFB. The Florida opportunities will be at 10:52 a.m. and 12:28 p.m. EDT, while the three Edwards AFB opportunities will be at 1:58 p.m., 3:34 p.m. and 5:10 p.m. EDT.

Weather at the Kennedy Space Center is forecast to be marginal on Wednesday, with a chance of rain showers within 30 miles of the Shuttle Landing Facility. Weather at Edwards AFB, however, is predicted to be ideal for all three landing opportunities, although NASA needs to land Endeavour in Florida to have any hope of maintaining its current flight schedule for late this year.

Thunderstorms and anvil clouds in the vicinity of the Kennedy Space Center has forced NASA to wave-off both of today's landing opportunities for shuttle Endeavour.

The bad weather has again delayed the homecoming of Endeavour and its seven member crew, including the three returning members of ISS Expedition 4 who will further extend their U.S. space endurance record to at least 196 days in orbit.

Looking at improved weather forecasts for Wednesday on both coasts, NASA decided against a landing attempt today at the backup site at Edwards AFB, California, hoping that the Florida weather would improve sufficiently for one last attempt tomorrow.

There are five landing opportunities available on Wednesday for Endeavour - two at the Kennedy Space Center and three at Edwards AFB. The Florida opportunities will be at 10:53 a.m. and 12:27 p.m. EDT, while the three Edwards AFB opportunities will be at 1:58 p.m., 3:33 p.m. and 5:11 p.m. EDT.

Weather at the Kennedy Space Center is forecast to be marginal on Wednesday, with a chance of rain showers within 30 miles of the Shuttle Landing Facility. Weather at Edwards AFB, however, is predicted to be ideal for all three landing opportunities, although NASA needs to land Endeavour in Florida to have any hope of maintaining its current flight schedule for later this year.

Barring an unforeseen deterioration in weather conditions, shuttle Endeavour will land on Wednesday but exactly where remains 'up in the air.'

There are five landing opportunities available on Wednesday for Endeavour - two at the Kennedy Space Center and three at Edwards AFB. The Florida opportunities will be at 10:53 a.m. and 12:27 p.m. EDT, while the three Edwards AFB opportunities will be at 1:58 p.m., 3:33 p.m. and 5:11 p.m. EDT.

Thunderstorms and anvil clouds in the vicinity of the Kennedy Space Center forced NASA to wave-off both landing opportunities for Endeavour on Tuesday. The bad weather again delayed the homecoming of the Endeavour and its seven member crew, including the three returning members of ISS Expedition 4 who will further extend their U.S. space endurance record to at least 196 days in orbit.

Counting on improved weather forecasts for Wednesday on both coasts, NASA decided against a landing attempt at the backup site at Edwards AFB, California on Tuesday, hoping that the Florida weather would improve sufficiently for one last attempt on Wednesday.

Weather at the Kennedy Space Center is forecast to be much improved on Wednesday, with only a chance of rain showers within 30 miles of the Shuttle Landing Facility. Weather at Edwards AFB, however, is predicted to be ideal for all three landing opportunities, although NASA needs to land Endeavour in Florida to have any hope of maintaining its current flight schedule for late this year.

An unexpected deterioration in Florida weather will likely force NASA to divert shuttle Endeavour to land at its Edwards AFB, California backup site where conditions are ideal.

The Spaceflight Meteorology Group's 5 a.m. EDT forecast now indicates the likelihood of rain showers and chance of broken clouds for Endeavour's first Florida landing opportunity, with thunderstorms added to the mix for the second. Radar shows a band of thunderstorms forming to the west of the Kennedy Space Center, with rain showers already skirting just to the north of Cape Canaveral.

Weather at the shuttle's backup landing site in California's Mojave Desert is predicted to be perfect for a homecoming of the Endeavour and its seven member crew, including the three returning members of ISS Expedition 4 who have extended their U.S. space endurance record to 196 days in orbit.

Here are today's five landing opportunities available for Endeavour - two at the Kennedy Space Center and three at Edwards AFB. The Florida opportunities will be at 10:53 a.m. and 12:27 p.m. EDT, while the three Edwards AFB opportunities will be at 1:58 p.m., 3:33 p.m. and 5:11 p.m. EDT.

The first indication to Endeavour's destination will occur at about 9:25 a.m. when flight controllers would decide whether to issue the 'Go for De-Orbit Burn' to attempt a landing on the first Florida opportunity - the burn would follow at 9:44 a.m. EDT. If waved-off, Endeavour will likely be pointed toward a landing on the first Edwards AFB opportunity, requiring a de-orbit burn at 12:50 p.m. EDT.

The seven astronauts and cosmonauts were awakened at 2:23 a.m. EDT to the sounds of the Sonny & Cher classic, "I Got You Babe."

An unexpected deterioration in Florida weather forced NASA to wave-off shuttle Endeavour from its first Florida landing opportunity and will likely divert the orbiter to land at its Edwards AFB, California backup site where conditions are ideal.

The Spaceflight Meteorology Group's 5 a.m. EDT forecast indicates the likelihood of rain showers, thunderstorms and broken clouds for Endeavour's second Florida landing opportunity. Radar shows a band of thunderstorms forming to the west of the Kennedy Space Center, with rain showers already skirting just to the north of Cape Canaveral.

Weather at the shuttle's backup landing site in California's Mojave Desert is predicted to be perfect for a homecoming of the Endeavour and its seven member crew, including the three returning members of ISS Expedition 4 who have extended their U.S. space endurance record to 196 days in orbit.

Here are today's four remaining landing opportunities available for Endeavour - one more at the Kennedy Space Center and three at Edwards AFB. The final Florida opportunity will be at 12:27 p.m. EDT, while the three Edwards AFB opportunities will be at 1:58 p.m., 3:33 p.m. and 5:11 p.m. EDT.

The key to Endeavour's final destination will occur at about 11 a.m. when flight controllers would decide whether to issue the 'Go for De-Orbit Burn' to attempt a landing on the final Florida opportunity - the burn would follow at 11:19 a.m. EDT. If waved-off, Endeavour will be pointed toward a landing on the first Edwards AFB opportunity, requiring a de-orbit burn at 12:50 p.m. EDT.

The seven astronauts and cosmonauts were awakened at 2:23 a.m. EDT to the sounds of the Sonny & Cher classic, "I Got You Babe."

An unexpected deterioration in Florida weather forced NASA to wave-off shuttle Endeavour from its first Florida landing opportunity and may divert the orbiter to land at its Edwards AFB, California backup site where conditions are ideal.

Thunderstorms and rain showers are approaching the Central Florida area and may impact Endeavour's second Florida landing opportunity. Radar shows a band of thunderstorms to the west of the Kennedy Space Center, and Mission Control just informed the crew that weather conditions are still "too close to call."

Weather at the shuttle's backup landing site in California's Mojave Desert is predicted to be perfect for a homecoming of the Endeavour and its seven member crew, including the three returning members of ISS Expedition 4 who have extended their U.S. space endurance record to 196 days in orbit.

Here are today's four remaining landing opportunities available for Endeavour - one more at the Kennedy Space Center and three at Edwards AFB. The final Florida opportunity will be at 12:27 p.m. EDT, while the three Edwards AFB opportunities will be at 1:58 p.m., 3:33 p.m. and 5:11 p.m. EDT.

The key to Endeavour's final destination will occur at about 11:10 a.m. when flight controllers would decide whether to issue the 'Go for De-Orbit Burn' to attempt a landing on the final Florida opportunity - the burn would follow at 11:19 a.m. EDT. If waved-off, Endeavour will be pointed toward a landing on the first Edwards AFB opportunity, requiring a de-orbit burn at 12:50 p.m. EDT.

Shuttle Endeavour will land in California after an unexpected deterioration in Florida weather forced NASA to wave-off the orbiter from both of its landing opportunities at the Kennedy Space Center.

Conditions at the backup landing site at Edwards AFB, California are ideal and Endeavour is scheduled to fire its engines in a de-orbit burn at 12:50 p.m. EDT, resulting in touchdown in the Mojave Desert at 1:58 p.m. EDT.

Thunderstorms and rain showers approaching the Central Florida area created an unacceptable risk to flight controllers. NASA desperately wanted to bring the shuttle back to Florida to retain any chance of maintaining its flight schedule for this year.

The California homecoming will also be bittersweet for the seven astronauts and cosmonauts, including the three returning members of ISS Expedition 4 - who have extended their U.S. space endurance record to 196 days in orbit - as their families were awaiting the return at the Florida landing strip.

Shuttle Endeavour has been cleared to fire its braking rockets for a landing in California's Mojave Desert where weather conditions are ideal for the spaceplane's return.

Commander Ken Cockrell and pilot Paul Lockhart have been the 'Go' for the de-orbit burn at 12:50 p.m. EDT, culminating in a landing at Edwards AFB, California at 1:58 p.m. EDT.

Endeavour was diverted to the west coast after an unexpected deterioration in Florida weather forced NASA to wave-off both of today's landing opportunities at the Kennedy Space Center. Thunderstorms and rain showers approaching Central Florida created an unacceptable risk to the shuttle and its crew, although NASA desperately wanted to land Endeavour in Florida to retain any chance of maintaining its flight schedule for later this year.

The California homecoming will also be bittersweet for the seven astronauts and cosmonauts, including the three returning members of ISS Expedition 4 - who have extended their U.S. space endurance record to 196 days in orbit - as their families were awaiting the return at the Florida landing strip.

Shuttle Endeavour has ignited its braking rockets to start a fiery plunge through Earth's atmosphere and a long, gliding descent to its backup landing site - Edwards AFB in California's Mojave Desert. The shuttle will land at 1:58 p.m. EDT at NASA's Dryden Flight Research Center where weather conditions are perfect for the spaceplane's return.

Commander Ken Cockrell and pilot Paul Lockhart completed a 2-minute, 55-second firing of Endeavour's twin Orbital Maneuvering System engines that began at 12:50 p.m. EDT to reduce the shuttle's velocity sufficiently to drop it out of orbit and begin an hour-long free-fall descent back to Earth. The orbiter will encounter the upper fringes of the atmosphere at about 400,000 feet in altitude, followed by a series of turns and banking maneuvers to slow the vehicle for its powerless touchdown on runway 22 on Rogers Dry Lake in the high desert of California's Antelope Valley.

The California homecoming will be bittersweet for the seven astronauts and cosmonauts, including the three returning members of ISS Expedition 4 - who have extended their U.S. space endurance record to 196 days in orbit - as their families were awaiting the shuttle's return at the Florida landing strip.

Endeavour was diverted to the West Coast after an unexpected deterioration in Florida weather forced NASA to wave-off both of today's landing opportunities at the Kennedy Space Center. Thunderstorms and rain showers approaching Central Florida created an unacceptable risk to the shuttle and its crew, although NASA desperately wanted to land Endeavour in Florida to retain any chance of maintaining its flight schedule for later this year.

Shuttle Endeavour has safely landed at Edwards AFB, California, ending a two-week mission to the International Space Station and the return of the record-setting ISS Expedition 4 crew.

Endeavour touched down at 1:58 p.m. EDT at its back-up landing strip, runway 22 at NASA's Dryden Flight Research Center, where weather conditions were perfect for the spaceplane's return.

Commander Ken Cockrell and pilot Paul Lockhart guided the orbiter on its fiery plunge through the atmosphere and hour-long free-fall descent back to Earth, then precisely executed a series of turns and banking maneuvers that slowed the vehicle for its powerless landing on the 3-mile long paved runway on Rogers Dry Lake in the high desert of California's Antelope Valley.

The California homecoming will be bittersweet for the seven astronauts and cosmonauts, including the three returning members of ISS Expedition 4 - who have extended their U.S. space endurance record to 196 days in orbit - as their families were awaiting the shuttle's return at the Florida landing strip.

Endeavour was diverted to the West Coast after an unexpected deterioration in Florida weather forced NASA to wave-off both of today's landing opportunities at the Kennedy Space Center. Thunderstorms and rain showers approaching Central Florida created an unacceptable risk to the shuttle and its crew, although NASA desperately wanted to land Endeavour in Florida to retain any chance of maintaining its flight schedule for later this year. The orbiter will now be ferried back to the Kennedy Space Center on the back of a 747 airliner, a procedure that lasts about a week at a cost of $1 million.

Commander Ken Cockrell, pilot Paul Lockhart and mission specialists Franklin Chang-Diaz and Phillippe Perrin have exited shuttle Endeavour, conducted the traditional "walkaround" of the orbiter and made a few brief remarks at the microphone at NASA's Dryden Flight Research Center at Edwards AFB in California's Mojave Desert.

The three returning members of the ISS Expedition 4 crew, Yuri Onufrienko, Carl Walz and Dan Bursch - who established a new U.S. space endurance record of 196 days in orbit - remained within the air-conditioned confines of the crew transport vehicle after exiting the orbiter to slowly acclimate their bodies to gravity after 6 months of weightlessness.

Endeavour touched down at 1:58 p.m. EDT at its back-up landing strip, runway 22 on Rogers Dry Lake, completing a successful crew exchange and servicing mission to the International Space Station lasting 13 days, 20 hours and 35 minutes.

The seven crew members will be driven back to the astronaut quarters at Dryden for medical tests and preliminary de-briefings. They will then return home to the Johnson Space Center in Houston on Thursday for a welcome home ceremony and a reunion with their families.

Endeavour was diverted to the West Coast after approaching thunderstorms forced NASA to wave-off both landing opportunities at the Kennedy Space Center for the third consecutive day. NASA desperately wanted to land Endeavour in Florida to have any hope of maintaining its flight schedule for later this year.

The orbiter will now be ferried back to the Kennedy Space Center on the back of a 747 jumbo jet, a complex procedure that consumes about a week and costs the space agency about $1 million. The cross-country trek will, in all likelihood, force Endeavour's next mission to be slipped by a few weeks into November.