Complete Coverage: Shuttle Endeavour's Last Voyage

The six astronauts aboard space shuttle Endeavour have exited the spacecraft after today's smooth landing at NASA's Kennedy Space Center at 2:35 a.m. ET (0635 GMT).

Endeavour's astronauts are stepping out of the bright orange pressure suits and donning their trademark blue jumpsuits in order to walk out on the runway to inspect Endeavour after its landing.

- Tariq Malik, (@tariqjmalik)

Shuttle Endeavour has landed for the 25th and last time.

The orbiter touched down on the runway of Kennedy Space Center's Shuttle Landing Facility at 2:35 p.m. EDT (0635 GMT).

-- Clara Moskowitz

CAPE CANAVERAL, Fla. – The space shuttle Endeavour is beginning its final approach for landing, encountering the Earth's upper atmosphere at an altitude of about 400,000 feet above the South Pacific Ocean. Watch it LIVE on NASA TV.

When re-entering the atmosphere, Endeavour's heat shield tiles will experience temperatures up to 2,500 degrees Fahrenheit.

The shuttle will now begin its glide to the 3-mile long runway at Kennedy Space Center's Shuttle Landing Facility. Endeavour is scheduled to touch down at 2:35 a.m. EDT (0635 GMT). This is the 77th shuttle landing at the Florida spaceport, and the 18th to land at night.

-- Denise Chow (@denisechow)

CAPE CANAVERAL, Fla. – Endeavour is beginning its descent through Earth's atmosphere to begin a long glide to Kennedy Space Center's Shuttle Landing Facility. The shuttle is expected to land at 2:35 a.m. EDT (0635 GMT). Watch it LIVE on NASA TV.

Commander Mark Kelly and pilot Greg Johnson completed a de-orbit burn of the twin Orbital Maneuvering System engines to slow the shuttle's velocity by about 188 miles per hour. The orbiter will still travel at a blistering Mach 25 and will get its first taste of Earth's upper atmosphere at an altitude of approximately 400,000 feet.

-- Denise Chow (@denisechow)

CAPE CANAVERAL, Fla. – Endeavour has been cleared to land at NASA's Kennedy Space Center by flight controllers on the ground. The shuttle is scheduled to touch down for the final time at 2:35 a.m. EDT (0635 GMT) at the Florida spaceport's Shuttle Landing Facility. Watch it LIVE on NASA TV.

Shuttle commander Mark Kelly and pilot Greg Johnson have been given the "go" to perform the de-orbit burn at around 1:29 a.m. EDT (0529 GMT). For the burn, the Endeavour's twin Orbital Maneuvering System engines will fire for 2 minutes and 31 seconds to slow the shuttle's velocity enough to begin its descent through Earth's atmosphere.

-- Denise Chow (@denisechow)

CAPE CANAVERAL, Fla. – The doors of the space shuttle Endeavour's payload bay were closed at 10:49 p.m. EDT (0249 June 1 GMT), in preparation for landing. Watch it LIVE on NASA TV.

Endeavour is scheduled to touch down at 2:35 a.m. EDT (0635 GMT) on Runway 15 at the Shuttle Landing Facility at NASA's Kennedy Space Center. At 1:29 a.m. EDT (0529 GMT), Endeavour is scheduled to perform its deorbit burn that will place it on course to land in Florida.

-- Denise Chow (@denisechow)

The six astronauts on space shuttle Endeavour were woken this evening at 6:57 p.m. EDT to the runner up tune in a NASA contest for original wakeup songs to play for the orbiter's last mission.

"We're looking forward to another busy day and hopefully getting home tomorrow," shuttle commander Mark Kelly said after hearing the song. "That song was the second place winner in the wakeup music contest by The Plunketts, called 'Dreams You Give.' It received something like over 600,000 votes. So congratulations to Brian Plunkett from Halfway, Missouri."

-- Clara Moskowitz

HOUSTON – The space shuttle Endeavour undocked from the space station for the final time tonight, slowly backing away from the orbiting outpost starting at 11:55 p.m. EDT (0355 May 30 GMT). Watch it LIVE on NASA TV.

"Houston and station, we have physical separation," shuttle commander Mark Kelly radioed to flight controllers at Mission Control in Houston.

Pilot Greg Johnson will now take the controls to fly the orbiter around the station at a distance of about 400 feet to collect data and take images of the complex. Following this victory lap, Mark Kelly will fly Endeavour through an unprecedented second loop, this time from about 1,000 feet away.

This procedure, which will set the orbiter up to "re-rendezvous" with the space station, is part of an intricate test of new sensor technologies, called STORRM, that will help future spacecraft perform automated dockings to the station and other potential destinations.

The STORRM test is scheduled to begin at 1:36 a.m. EDT (0536 GMT). The maneuver will reach its closest re-approach with the space station at around 3:28 a.m. EDT (0728 GMT). Instead of coming in to dock with the station, however, Endeavour will make a final separation burn to take it away from the space station at 4:38 a.m. EDT (0838 GMT).

Read more about the STORRM test here.

After pulling away from the station, the six astronauts will then begin their two-day orbital journey home. Endeavour is scheduled to land at NASA's Kennedy Space Center in Florida at 2:35 a.m. EDT (0635 GMT) on June 1.

-- Denise Chow (@denisechow)

HOUSTON – Endeavour's astronauts woke up at 7:27 p.m. EDT (2327 GMT) today to the song "Slowness" by Tucson-based band Calexico. The song was played specially for commander Mark Kelly. Watch it LIVE on NASA TV.

"Good morning, Houston, and good morning, Tucson, Arizona as well," Kelly said. "That song is from a band named Calexico, from my wife Gabby's hometown. They're from Tucson, Arizona as well. It's about two people on a trip, reaching across a distance, and it references places like Signal Hill and Gate Pass in Tucson. I know she really wants to get back there and is really looking forward to that. So, it's an appropriate song because that's coming soon."

The astronauts have a busy day ahead of them, and are scheduled to undock from the International Space Station tonight to begin their journey home to Earth.

Here's a look at today's schedule in space (all times subject to change):

7:27 p.m. EDT – Endeavour / ISS crew wake up

11:55 p.m. EDT – Endeavour undocks from ISS

Monday, May 30

12:22 a.m. EDT – Endeavour flyaround of ISS begins

1:36 a.m. EDT – Endeavour STORRM test begins

3:28 a.m. EDT – Endeavour STORRM test closest re-approach to ISS

4:38 a.m. EDT – Endeavour final separation from ISS

6:30 a.m. EDT – Mission Status Briefing

7:56 a.m. EDT – Shuttle VTR playback of undocking

10:56 a.m. EDT – Endeavour crew sleep begins
 

HOUSTON – Endeavour's STS-134 astronauts and the International Space Station's Expedition 28 crew gathered for a farewell ceremony before the hatches were closed between the station and orbiter. Watch it LIVE on NASA TV.

The hatches between the two spacecraft were closed at 7:23 a.m. EDT (1123 GMT) after being docked 10 days, 23 hours and 45 minutes.

"I just want to say on behalf of the STS-134 crew that we had a very successful mission working with Expedition 28," shuttle commander Mark Kelly said at the farewell ceremony. "It's been a great number of days docked. We're looking forward to getting home and we're going to leave these guys to a little peace and quiet."

The two crews exchanged handshakes and hugs before Endeavour's six astronauts floated through the hatch into the shuttle. The shuttle crew will begin their sleep period at 11:26 a.m. EDT (1526 GMT). The orbiter is scheduled to make its final undocking from the space station later tonight at 11:55 a.m. EDT (0355 May 30 GMT).
 

HOUSTON – After astronauts conducted a final inspection of shuttle Endeavour's heat shield while the vehicle is docked to the International Space Station, mission managers here at NASA's Johnson Space Center have officially cleared the orbiter for its upcoming re-entry to Earth and landing on Wednesday (June 1). Watch it LIVE on NASA TV.

Endeavour is scheduled to undock from the space station on Sunday (May 29) at 11:53 p.m. EDT (0353 May 30 GMT). The shuttle crew is currently asleep after a busy day that included the mission's fourth and final spacewalk. The astronauts are scheduled to wake up tonight at 7:56 p.m. EDT (2356 GMT).

-- Denise Chow (@denisechow)

Spacewalkers Mike Fincke and Greg Chamitoff have finished up all their tasks for today's outing and have come back inside the space station's airlock.

Today's spacewalk was the last to be conducted by a space shuttle crew during a shuttle mission.

"Wanted to say congrats to the shuttle program for all the wonderful successes we've had. We've come a long way. From me and Greg and the rest of the crew, congratulations," Fincke told Mission Control.

-- Clara Moskowitz

HOUSTON – Spacewalkers Mike Fincke and Greg Chamitoff swapped out grapple fixtures on the newly installed space station boom, replacing some shuttle-specific hardware with a fixture that will enable its new use on the space station.

Fincke was originally supposed to store the removed fixture in Endeavour's payload bay, but to save time, it will instead be brought back into the station's airlock with the spacewalkers at the end of today's outing. Watch it LIVE on NASA TV.

The astronauts are now working on a spare arm for the station's Dextre robot, which is located on a storage pallet outside the station. Fincke and Chamitoff are releasing three tricky bolts, making use of a specially designed pry rod.

Mission Control in Houston made the decision to extend the spacewalk to approximately 7 hours and 30 minutes to give the astronauts enough time to accomplish all their major objectives. As a result, Chamitoff will need to recharge his oxygen.

Earlier in the spacewalk, a major milestone was passed: astronauts and cosmonauts have now spent over 1,000 hours spacewalking for the assembly and maintenance of the International Space Station. The milestone was reached at 5:02 a.m. EDT.

-- Denise Chow (@denisechow)

HOUSTON – The space shuttle Endeavour's Orbiter Boom Sensor System, a 50-foot (15-meter) inspection pole used to examine the vehicle's heat shield, was successfully installed onto the starboard side of the space station's backbone-like truss. Watch it LIVE on NASA TV.

The boom's installation, which was one of the primary objectives of today's spacewalk, was completed at 1:42 a.m. EDT (0542 GMT).

"On behalf of the STS-134 crew and Expedition 27 crew, space station assembly is complete," shuttle commander Mark Kelly radioed to Mission Control in Houston after the inspection pole was attached to its new home.

Spacewalkers Mike Fincke and Greg Chamitoff will now install some connectors and a foot restraint on the station's robotic arm before moving to the port segment of the truss to retrieve an electrical grapple fixture to install on the boom itself.

-- Denise Chow (@denisechow)

HOUSTON – Shuttle pilot Greg Johnson and station astronaut Ron Garan are maneuvering the space station's robotic arm, which is holding Endeavour's 50-foot (15-meter) inspection pole, into place on the starboard side of the station's truss structure. Watch it LIVE on NASA TV.

As the robotic arm moves the pole toward its new permanent home on the station's truss, spacewalkers Mike Fincke and Greg Chamitoff prepare to deftly install the boom on the exterior of the station. Working in close proximity to the robotic arm and the attached boom, the spacewalkers were instructed to handle the inspection pole with, "a graceful ballerina touch."

The inspection pole, which is called the Orbiter Boom Sensor System, is being left at the station to be used as an extension of the outpost's robotic arm.

-- Denise Chow (@denisechow)

HOUSTON – Endeavour's robotic arm has handed off the orbiter's 50-foot (15-meter) long inspection pole to the station's robotic arm, officially making it part of the space station program. The exchange occurred at 12:50 a.m. EDT (0450 GMT). Watch it LIVE on NASA TV.

During today's spacewalk, astronauts Mike Fincke and Greg Chamitoff will attach the pole, known as the Orbiter Boom Sensor System (OBSS) to its new permanent home, on the starboard side of the station's backbone-like truss structure. The boom will be used as an extension of the station's robotic arm, giving it added reach for future uses.

-- Denise Chow (@denisechow)

HOUSTON – Astronauts Mike Fincke and Greg Chamitoff have switched their suits onto battery power and opened the outer hatch of the station's Quest airlock, signifying the start of today's spacewalk. Watch it LIVE on NASA TV.

The official start time of the spacewalk was 12:15 a.m. EDT (0415 GMT). Today's outing – the final spacewalk of Endeavour's STS-134 mission, and the last one conducted by shuttle crewmembers – is scheduled to last about 6 1/2 hours.

Read more about the spacewalk objectives here

HOUSTON – In preparation for Friday's spacewalk, mission specialists Mike Fincke and Greg Chamitoff began their overnight stay in the station's Quest airlock at 10:21 a.m. EDT (1421 GMT). The pressure in the airlock is lowered, and the two spaceflyers remain in the compartment overnight to help their bodies adjust to the rigors of taking a spacewalk. Watch it LIVE on NASA TV.

Prior to going to sleep, and also once again in the morning, the astronauts don oxygen masks to help purge the nitrogen from their bloodstreams. This helps them reduce the risk of getting decompression sickness, or "the bends," inside their spacesuits.

Endeavour's crew is scheduled to wake up at 7:56 p.m. EDT (2356 GMT) tonight to begin spacewalk preparations. The planned 6 1/2-hour spacewalk is scheduled to start at around 12:46 a.m. EDT (0446 GMT) on Friday.

-- Denise Chow (@denisechow)

HOUSTON – Endeavour's astronauts have another busy day ahead of them on the International Space Station. The six spaceflyers woke up today at 7:56 p.m. EDT (2356 GMT) to the song "Countdown" by Rush. The song was specially played for mission specialist Mike Fincke. Watch it LIVE on NASA TV.

Here's a look at today's schedule in space:

7:56 p.m. EDT – Endeavour / ISS crew wake

10:56 p.m. EDT – OBSS late inspection of Endeavour's thermal protection system

11:02 p.m. EDT – Live interviews with KVOA-TV, Tucson, AZ / KUAT-TV, Tucson, AZ / KGUN-TV, Tucson, AZ / KOLD-TV, Tucson, AZ

5:42 a.m. EDT – Join crew news conference

6:30 a.m. EDT – Mission Status Briefing

7:51 a.m. EDT – Spacewalk #4 procedure review

10:21 a.m. EDT – Spacewalk #4 campout begins (Fincke & Chamitoff)

11:26 a.m. EDT – Endeavour / ISS crew sleep begins

-- Denise Chow (@denisechow)

HOUSTON – The third spacewalk of Endeavour's STS-134 mission ended at 8:37 a.m. EDT (1237 GMT). Spacewalkers Andrew Feustel and Mike Fincke were outside the International Space Station for a total of 6 hours and 54 minutes. Watch it LIVE on NASA TV.

Feustel and Fincke are now back inside the station's Quest airlock. This was the 247th spacewalk conducted by U.S. astronauts.The Endeavour astronauts are scheduled to begin sleeping at 11:56 a.m. EDT (1556 GMT) after a busy day on orbit.

-- Denise Chow (@denisechow)

Pressing ahead with the remaining tasks for the day, the spacewalkers will take photographs of the Russian Zarya control module's thrusters and infrared images of an experiment installed on the station's exterior. Watch it LIVE on NASA TV.

While performing some cleanup work and translating to the new work site, astronaut Andrew Feustel reported that his right eye was stinging and watering, causing him quite a bit of discomfort.

After taking a short break and rubbing his eye against something in his helmet, Feustel said it stopped hurting and he was able to continue with the work ahead.

"Ok, feeling better," Feustel told Chamitoff and flight controllers in Houston. "My eye feels much, much better."

-- Denise Chow (@denisechow)

HOUSTON – Mission specialist Andrew Feustel made his way over to astronaut Mike Fincke's work area to help him get untangled from a safety tether that was around his leg. Fincke is on the space station's Unity node connecting power cables that will stretch over to the Russian Zarya control module. Watch it LIVE on NASA TV.

Feustel was at the Russian module also connecting power cables and will return to his work area after helping Fincke with his tether situation. The two spacewalkers are installing power cables to provide added redundancy to the power system in the Russian segment of the space station.
 

-- Denise Chow (@denisechow)

HOUSTON – Astronaut Mike Fincke is working on connecting a complicated set of power cables on the space station's U.S. Unity node. Earlier in the spacewalk, Feustel and Fincke laid the groundwork for this task by connecting similar cables on the station's port side. Watch it LIVE on NASA TV.

Meanwhile, Feustel is on the Russian segment of the space station doing similar cabling work. These cables, which stretch between the Unity node and the Russian Zarya control module, will be used to provide backup power between the two segments.

-- Denise Chow (@denisechow)

HOUSTON – Spacewalkers Andrew Feustel and Mike Fincke are now installing a cable for an external wireless system on the exterior of the space station's U.S. Destiny laboratory. Watch it LIVE on NASA TV.

This task was originally scheduled to be completed during the mission's first spacewalk, but a glitch with the carbon dioxide sensor on spacewalker Greg Chamitoff's suit forced mission managers to end that outing early. Flight controllers deferred the cable installation to today's excursion instead. Feustel and Fincke are now finishing that cabling work at the interface between the Destiny laboratory and the connected U.S. Harmony module.

-- Denise Chow (@denisechow)

HOUSTON – Spacewalkers Andrew Feustel and Mike Fincke are working to re-route a series of cables to beef up power to the Russian segment of the International Space Station and give the area added redundancy. Watch it LIVE on NASA TV.

The newly installed cables will stretch from the American Unity module to the Russian Zarya control module, and will help to strengthen the electrical system between the two segments.

So far, the spacewalk has gone very smoothly, NASA officials said. Feustel and Fincke are working well through their tasks and are about 30 minutes ahead of their timeline.

-- Denise Chow (@denisechow)

HOUSTON – Spacewalker Andrew Feustel is working through the second task of the spacewalk, to install a video signal converter on the space station's Russian Zarya control module. Watch it LIVE on NASA TV.

The astronauts are approximately 1 hour and 40 minutes into today's planned 6 1/2-hour spacewalk. 

-- Denise Chow (@denisechow)

HOUSTON – The two spacewalkers have successfully attached a power and data grapple fixture to the exterior of the station's Russian Zarya control module. The fixture, which will help to extend the reach of the station's robotic arm, was attached to the interface between the Zarya module and the American Unity node. Watch it LIVE on NASA TV.

Feustel retrieved the grapple fixture from inside the station's Quest airlock after both him and Fincke removed some multi-layer thermal blankets from the work site.

-- Denise Chow (@denisechow)

HOUSTON – Spacewalkers Andrew Feustel and Mike Fincke are setting up work at the station's Russian Zarya control module. The astronauts are preparing to add a power and data grapple fixture to the exterior of the module that will allow the station's robotic arm to access the segment using the fixture as a base. Watch it LIVE on NASA TV.

"Nice view of the Cupola from here," Feustel said from his work area.
Read more about the objectives of the third spacewalk of the mission.

-- Denise Chow (@denisechow)

HOUSTON – Astronauts Andrew Feustel and Mike Fincke have turned their spacesuits onto internal battery power and opened the space station's Quest airlock hatch to begin the third spacewalk of shuttle Endeavour's STS-134 mission. The spacewalk officially began at 1:43 a.m. EDT (0543 GMT). Watch it LIVE on NASA TV.

Today's outing is expected to last about 6 1/2 hours, with Feustel and Fincke scheduled to perform several tasks to upgrade the International Space Station.

Read more about the objectives of the third spacewalk of the mission.
 

-- Denise Chow (@denisechow)

HOUSTON – The hatchway that separates the equipment room from the crew portion of the station's Quest airlock has been sealed, separating spacewalkers Andrew Feustel and Mike Fincke from the rest of the space station. Watch it LIVE on NASA TV.

Shuttle commander Mark Kelly and station astronaut Ron Garan performed leak checks before beginning the depressurization process of the airlock. This takes roughly 30 minutes, and slowly depressurizes the airlock to the vacuum of space, which enables the spacewalkers to open the outer hatch to begin the mission's third spacewalk.

-- Denise Chow (@denisechow)

HOUSTON – Spacewalkers Andrew Feustel and Mike Fincke have begun doing some callisthenic exercises inside their pressurized spacesuits to prepare for their 6 1/2-hour excursion outside the International Space Station. Watch it LIVE on NASA TV.

The new In-Suit Light Exercise (ISLE) protocol is being tested prior to today's spacewalk, as a replacement for the overnight campout in the station's Quest airlock prior. If the new method is successful, the exercises may also be used before the mission's fourth spacewalk, which is scheduled to begin at around 12:46 a.m. EDT (0446 GMT) on Friday (May 27).

-- Denise Chow (@denisechow)

Crew is running about 10 minutes ahead of preparations for the third spacewalk of the mission. The spacewalk is expected to begin at around 1:46 a.m. EDT (0546 GMT). Watch it LIVE on NASA TV.

Spacewalkers Andrew Feustel and Mike Fincke are inside their bulky white spacesuits, and their crewmates, station astronaut Ron Garan and shuttle commander Mark Kelly, will now begin a series of leak checks. After that, Feustel and Fincke will experiment with a new method of spacewalk preparation, called In-Suit Light Exercise (ISLE).

This new method has the spacewalkers engaging in some callisthenic exercises, such as lifting their arms and legs while inside the pressurized spacesuit, and then doing breathing exercises while at rest. These preparations are done to help the astronauts adjust their bodies to the spacewalking environment, as well as help them combat decompression sickness, which is commonly known as "the bends."

Read more about the mission's third spacewalk here.

-- Denise Chow (@denisechow)

The six shuttle astronauts woke up today at 7:56 p.m. EDT (2356 GMT) to begin preparations before the day's spacewalk. The song "Real World" by Matchbox 20, was played to wake up the shuttle crew. It was specially selected for Endeavour pilot Greg H. Johnson. Watch it LIVE on NASA TV.

Here's a look at today's schedule in space:

7:56 p.m. EDT: Endeavour / ISS wake up

9:11 p.m. EDT: Spacewalk #3 ISLE preparations begin

11:36 p.m. EDT: Spacewalk #3 ISLE method crew pre-breathe begins (Feustel & Fincke)

Wed. May 25

12:31 a.m. EDT: Endeavour / ISS transfers resume

1:46 a.m. EDT: Spacewalk #3 begins

8:16 a.m. EDT: Spacewalk #3 ends

10:00 a.m. EDT: Mission Status Briefing

11:26 a.m. EDT: ISS crew sleep begins

11:56 a.m. EDT: Endeavour crew sleep begins

-- Denise Chow (@denisechow)

HOUSTON -- The shuttle crew performed several space station maintenance tasks today, including installing a new filter inside the station's Oxygen Generation System, which continually scrubs carbon dioxide from the air whenever the system's recirculation loop is running. Watch it LIVE on NASA TV.

Meanwhile, spacewalkers Mike Fincke and Andrew Feustel reviewed procedures for the mission's third spacewalk on Wednesday. The six-astronaut shuttle crew went to sleep at 11:56 a.m. EDT (1556 GMT) to rest up for the next day's activities.

-- Denise Chow (@denisechow)

Recovery crews have removed all three Soyuz crewmembers from their TMA-20 spacecraft after today's smooth landing on the steppes of Kazakhstan. Watch it LIVE on NASA TV.

All three spaceflyers are in good health and all smiles following their return to Earth, which ended a five-month mission on the International Space Station. They will undergo routine medical checks before heading back to a staging area to return to their home countries.

-- Denise Chow (@denisechow)

HOUSTON – The Soyuz capsule carrying Dmitry Kondratyev, Cady Coleman and Paolo Nespoli has safely landed in Kazakhstan, wrapping up more than five months in orbit for the veteran spaceflyers. Watch it LIVE on NASA TV.

Ground recovery teams confirmed visual sighting of the Soyuz parachute deployment were dispatched to the landing site. Kondratyev, Coleman and Nespoli landed on the steppes of Kazakhstan in Central Asia at 10:26 p.m. EDT (0226 Tuesday GMT) after spending 159 days in space. Watch it LIVE on NASA TV.

After landing, the three spaceflyers will board three separate helicopters with medical personnel to take them to a staging site before boarding planes to their respective home countries.

-- Denise Chow (@denisechow)

HOUSTON – At 10:11 p.m. EDT (0211 Tuesday GMT), the parachutes on the Soyuz capsule were opened, helping to slow the vehicle for landing. Watch it LIVE on NASA TV.

"We're feeling good," Russian spaceflyer Dmitry Kondratyev reported prior to the parachute deployment.

Kondratyev, Cady Coleman and Paolo Nespoli are scheduled to touch down on the steppes of Kazakhstan at 10:26 p.m. EDT (0226 Tuesday GMT). The weather at the landing site in Central Asia is very favorable, said NASA spokesman Rob Navias.

-- Denise Chow (@denisechow)

HOUSTON – The Soyuz spacecraft carrying Dmitry Kondratyev, Cady Coleman and Paolo Nespoli back to Earth has begun the final phase of its journey. The capsule began its atmospheric entry at 10:03 p.m. EDT (0203 Tuesday GMT). Watch it LIVE on NASA TV.

Approximately eight minutes after entering the atmosphere, the command will be given to open the parachutes. Two pilot parachutes are first deployed, the second of which extracts the drogue chute to slow the Soyuz descent rate.

-- Denise Chow (@denisechow)

HOUSTON – The three astronauts onboard a returning Soyuz vehicle performed a de-orbit burn at 9:36 p.m. EDT (0136 Tuesday GMT), to help the spacecraft with its re-entry into Earth's atmosphere. Watch it LIVE on NASA TV.

The engines of the Soyuz capsule were fired when the spacecraft was about 7.5 miles (12 kilometers) away from the International Space Station. The de-orbit burn lasted for about 4 minutes and 16 seconds, enabling the vehicle to slow down and drop from orbit. The Soyuz will begin entering the atmosphere at 10:03 p.m. EDT (0203 Tuesday GMT).

Dmitry Kondratyev, Cady Coleman and Paolo Nespoli remain on schedule to land on the barren steppes of Kazakhstan at 10:26 p.m. EDT (0226 Tuesday GMT).

-- Denise Chow (@denisechow)

HOUSTON — Endeavour's six astronauts woke up today at 8:26 p.m. EDT (0026 Tuesday GMT) to begin a relaxing off day aboard the International Space Station. The song "Svegliarsi La Mattina," by the Italian duo Zero Assoluto, was played to wake up the shuttle crew. It was specially selected for Endeavour mission specialist Roberto Vittori, an Italian astronaut.

"Good morning, Houston," Vittori said. "Thank you for playing that song. 'Svegliarsi la mattina' means 'You wake up in the morning.'"

Today, the spaceflyers will enjoy some down time in preparation for a busy spacewalk on Wednesday (May 25). Later tonight, a Russian-built Soyuz spacecraft will land in Kazakhstan, returning three astronauts home to Earth after a months-long stay at the space station. Watch it LIVE on NASA TV.

Here's a look at the shuttle and station crew's schedule:

8:26 p.m. EDT: Endeavour / Ron Garan wake up

10:26 p.m. EDT: Expedition 27 Soyuz TMA-20 landing

11:31 p.m. EDT: ISS crew sleep begins

Tues., May 24

12:26 a.m. EDT: Spacewalk #3 equipment preparations

12:36 a.m. EDT: Live interviews with KPIX-TV, San Francisco, CA / KGO-TV, San Francisco, CA / KFBK Radio, Sacramento, CA

1:00 a.m. EDT: Mission Status Briefing

6:41 a.m. EDT: Endeavour crew off-duty period begins

6:43 a.m. EDT: Live interviews with The Daily / KDKA-TV, Pittsburgh, PA / Pittsburgh Tribune, Pittsburgh, PA / KTRK-TV, Houston, TX

8:26 a.m. EDT: Spacewalk #3 procedure review

9:30 a.m. EDT: Mission Status Briefing

11:26 a.m. EDT: Ron Garan sleep begins

10:56 a.m. EDT: Endeavour crew sleep begins

-- Denise Chow (@denisechow)

HOUSTON – The Russian-built Soyuz spacecraft conducted what is called a "back away burn" to further separate it from the International Space Station. Watch it LIVE on NASA TV.

The burn was initiated following the image acquisition maneuver, during which Italian astronaut Paolo Nespoli photographed the space station and visiting shuttle Endeavour from the upper module of the Soyuz capsule.

Nespoli and his crewmates, Russian cosmonaut Dmitry Kondratyev and NASA astronaut Cady Coleman, will now continue their journey back to Earth. The Soyuz is expected to complete a de-orbit burn at 9:36 p.m. EDT (0136 Tuesday GMT) before re-entering Earth's atmosphere. 

-- Denise Chow (@denisechow)

HOUSTON – After undocking from the space station, Russian cosmonaut Dmitry Kondratyev backed the Soyuz spacecraft away to a distance of 656 feet (200 meters) to begin acquiring special images of the International Space Station and space shuttle Endeavour.

Kondratyev is holding the spacecraft in place as his crewmate, Italian astronaut Paolo Nespoli, moves to an upper module of the Soyuz to take pictures of the space station and docked shuttle. Watch it LIVE on NASA TV.

Nespoli will take still images and video of the view from the Soyuz, and the images will be brought back to Earth with the returning crew.

-- Denise Chow (@denisechow)

HOUSTON – Russian cosmonaut Dmitry Kondratyev, NASA astronaut Cady Coleman and Italian astronaut Paolo Nespoli undocked from the International Space Station in their Soyuz spacecraft at 5:35 p.m. EDT (2135 GMT). Watch it LIVE on NASA TV.

This is the first time that a Soyuz spacecraft has undocked from the station with a space shuttle also attached.

The capsule will now back away from the station to a distance of 656 feet (200 meters) before the onboard astronauts conduct a special photo opportunity of the space station and attached shuttle Endeavour. Nespoli will have five to ten minutes to capture the unique views of the space station and shuttle, before him and his crewmates continue with their journey back to Earth.

-- Denise Chow (@denisechow)

HOUSTON – Three space station residents – Russian cosmonaut Dmitry Kondratyev, NASA astronaut Cady Coleman and Italian astronaut Paolo Nespoli – are gearing up for their return home, after spending more than five months onboard the orbiting outpost.

The hatches between the International Space Station and the departing Soyuz TMA-20 spacecraft were closed at 2:45 p.m. EDT (1845 GMT). The three spaceflyers are scheduled to land tonight in Kazakhstan at 10:26 p.m. EDT (0226 Tuesday GMT). Watch it LIVE on NASA TV.

With the hatches closed, Kondratyev, Coleman and Nespoli will now don their Russian Sokol launch and entry suits, and perform a variety of pressure and leak checks on the suits and hatches.

-- Denise Chow (@denisechow)

HOUSTON – Shortly after the shuttle astronauts went to sleep at 12:26 p.m. EDT (1626 GMT), a warning alarm went off on the station, indicating an issue in the crew's sleeping quarters. The cause of the alarm was traced to a ziplock bag that had floated into the area and clogged one of the ventilation fans, station astronauts Ron Garan and Paolo Nespoli told flight controllers on the ground in Houston. Watch it LIVE on NASA TV.

The caution signal was quickly cleared, and the station astronauts reported that the fans were up and running again with no issues. The shuttle astronauts are sleeping now after enjoying a day off. They are scheduled to wake up tonight at 8:26 p.m. EDT.

-- Denise Chow (@denisechow)

The crew of Endeavour has begun what promises to be a busy day at the International Space Station, with Mission Control rousing the six astronauts at 10 p.m. ET (0200 GMT) with the song "Times Like These" by the band Foo Fighters. The tune was selected for Endeavour mission specialist Andrew Feustel by his family.

The major activity in space over the next day will be the return to Earth of a Soyuz capsule bring three space station crewmembers back home. Watch it LIVE on NASA TV.

Here's a look at the joint crew's schedule:

10:45 p.m. ET: EDUCATIONAL EVENT WITH MESA VERDE ELEMENTARY SCHOOL IN TUCSON, AZ

Mon., May 23

9:26 a.m. ET: EXPEDITION 27 / SOYUZ-TMA 20 UNDOCKING PREPARATIONS BEGIN

9:31 a.m. ET: ESA / ASI VIP EVENT WITH ITALIAN PRESIDENT GIORGIO NAPOLITANO

10 a.m. ET: MISSION STATUS BRIEFING

2 p.m. ET: EXPEDITION 27 SOYUZ TMA-20 FAREWELL AND HATCH CLOSURE COVERAGE (hatch closure at 1:30pm CT)

5:15 p.m. ET: EXPEDITION 27 SOYUZ TMA-20 UNDOCKING AND IMAGERY ACQUISITON COVERAGE (undocking at 4:35pm)

9:15 p.m. ET: EXPEDITION 27 SOYUZ TMA-20 LANDING COVERAGE (deorbit burn at 8:36pm CT; landing at 9:26pm CT)

-- Tariq Malik (@tariqjmalik)

Spacewalker Mike Fincke hit a snag while working to remove 22 covers protecting the space station's port side solar array gear when some bolts and washers popped loose, prompting some replanning by Mission Control. Watch it LIVE on NASA TV.

At least one bolt floated away and another was caught by Fincke before it could stray too far, prompting Mission Control to laude Fincke, saying he'd earned "golden glove award" for the catch. Mission Control wants to make sure that no wayward bolts or washers get stuck in the large Solar Alphay Rotary Joint, a gear that turns outboard solar arrays like a paddlewheel to track the sun.

Mission Control told the spacewalkers they'd likely do a partial lubrication job, rather than a complete one, to limit the chance of more bolts being released.

-- Tariq Malik (@tariqjmalik)

Astroanuts Andrew Feustel and Mike Fincke are hard at work outside the International Space Station during the second spacewalk of their STS-134 mission, which began today at 2:05 a.m. EDT (0605 GMT).

Today's spacewalk has two primary goals. The astronaut are refilling a leaky ammonia coolant supply on the station and greasing up a huge solar array gear on the orbiting lab. The spacewalk is set to last about 6 1/2 hours.

-- Tariq Malik (@tariqjmalik)

Astronauts on space shuttle Endeavour have woken up for a busy day of spacewalking outside the International Space Station.

Mission Control roused the crew at 9:27 p.m. EDT (0127 May 22 GMT) to the Italian song "Il Mio Pensiero" by singer Luciano Ligabue. The tune was chosen for Italian astronaut Roberto Vittori, an Endeavour mission specialist representing the European Space Agency.

Today, Endeavour's crew will perform the mission's second spacewalk, a 6 1/2-hour excursion to refill ammonia radiators, vent an old ammonia coolant tank and lubricate a huge solar array joint and parts of a maintenance robot.

The spacewalk will begin at 2:16 a.m. EDT (0616 GMT).

Today is Flight Day 7 of Endeavour's 16-day mission to the International Space Station.

-- Tariq Malik (@tariqjmalik)

Astronauts on shuttle Endeavour and the International Space Station will get a very special phone call today when Pope Benedict XVI rings from the Vatican at 7 a.m. ET (1100 GMT) today.

Mission Control roused the crew at 9:26 p.m. EDT (1326 GMT) with the song "In View" by the band The Tragically Hip. The tune was selected for Endeavour mission specialist and spacewalker Andrew Feustel by his family.

Endeavour astronaut have a few hours of time off today to rest from their busy flight, and later they will inspect a ding in a heat shield tile on Endeavour's belly before the papal call.

Today is Flight Day 6 of Endeavour's 16-day mission to the International Space Station.

-- Tariq Malik (@tariqjmalik)

HOUSTON -- The first of four spacewalks planned for the shuttle Endeavour's STS-134 mission officially ended at 9:29 a.m. EDT (1329 GMT), after a total of six hours, 19 minutes. Watch it LIVE on NASA TV.

Endeavour's spacewalk team - Drew Feustel, Greg Chamitoff, and Mike Fincke, still have three more spacwalks to go during the remainder of the 16-day mission at the International Space Station.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- Both Drew Feustel and Greg Chamitoff are back inside the space station's airlock, after spending about six hours spacewalking. Watch it LIVE on NASA TV.

The two had a productive day, but had to cut their spacewalk short because of a glitch with Chamitoff's carbon dioxide sensor.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON-- Chamitoff's broken carbon dioxide sensor means that NASA can't tell for sure how many consumables he has left in his spacesuit. Mission managers were forced to make a conservative estimate, which does not allow enough time for the spacewalkers to complete one of their scheduled final tasks - the removal of a space debris shield to connect umbilical cords to the new antennas. Watch it LIVE on NASA TV.

Instead, the spacewalkers will clean up and wrap up early.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON-- The two spacewalkers have successfully installed two new communications antennas outside the International Space Station's Destiny Lab. Watch it LIVE on NASA TV.

The astronauts are about 15 minutes behind schedule, but they should be able to make up the time in their remaining two hours of spacewalking. A sensor on Chamitoff's spacesuit that monitors carbon dioxide has also failed, so he will monitor himself for any symptoms of excess carbon dioxide.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- The two spacewalkers have been breezing through most of their activities for the day, and now are focusing on their final major job for the day: the installation of a new communications antenna. Watch it LIVE on NASA TV.

The process should take about two and a half hours.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- Spacewalkers Drew Feustel and Greg Chamitoff have accomplished some tasks that will save time during the mission's next spacewalk, scheduled for Sunday (May 22). During that spacewalk astronauts will top off the ammonia coolant in a leaking system on the space station's exterior. Watch it LIVE on NASA TV.

The spacewalkers installed a jumper cable and vented some nitrogen from the system.

"Alright boys, keep up the good work," astronaut Mike Fincke said from inside the space station. "This is a lot of fun."

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON-- Spacewalker Drew Feustel has completed the job of installing a protective cover on a joint that controls the movement of one of the space station's solar arrays, called the Solar Alpha Rotary Joint. Watch it LIVE on NASA TV.

Meanwhile spacewalker Greg Chamitoff is back in the airlock for a brief recharge of his spacesuit's oxygen supply.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- Spacewalker Drew Feustel has finished installing a new experiment, MISSE 8, to replace the old one he and Chamitoff collected from the outside of the International Space Station. This experiment will expose materials to the space environment for about six months to a year to test how the materials react. Watch it LIVE on NASA TV.

"That is also another major mission objective milestone so congratulations," astronaut Mike Fincke told the spacewalkers from inside the space station.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- The spacewalkers have retrieved a completed science experiment called MISSE 7, which had exposed materials to the space environment, and have stowed it into the shuttle's payload bay to be carried back to Earth. Watch it LIVE on NASA TV.

Astronaut Greg Chamitoff secured the experiment to the payload bay's side wall, after initially having trouble closing the latches.

"We're having trouble getting the latches closed," spacewalk coordinator, astronaut Mike Fincke, told Mission Control. "He's giving a really strong effort  and hes a really strong guy."

However, after some tips from Mission Control, Chamitoff got the job done.

"Thanks for the advice," Fincke told ground controllers. "Remind me to call you more often."

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- Spacewalkers Feustel and Chamitoff have arrived at their first work site, an experiment called MISSE (Materials International Space Station Experiment), which exposes materials to the environment of space to see how they respond. Watch it LIVE on NASA TV.

"A beautiful MISSE experiment," Feustel said upon arriving at the scene.

The spacewalkers will retrieve a set of materials that have been stored there for about a year, and exchange those with new materials to be tested.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON-- Spacewalkers Drew Feustel and Greg Chamitoff are getting going on their first spacewalk of the STS-134 mission. Watch it LIVE on NASA TV.

"It's a dream come true for me," said Chamitoff, who is making his first spacewalk.

"Welcome to space, buddy," Feustel said. He also took a moment to say hi to friends, family and others watching today's spacewalk from the ground.

"I know folks at home are watching," Feustel said. "I just want to say hi to everybody. Thanks for coming out to watch. A special hello to my wife Indi, a great sport."

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- Astronauts Drew Feustel and Greg Chamitoff have opened the hatch of their airlock to space and officially begun the first spacewalk of their STS-134 shuttle mission. Watch it LIVE on NASA TV.

The official spacewalk start time was 3:10 a.m. EDT (0710 GMT).

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON-- Spacewalkers Drew Feustel and Greg Chamitoff are fully suited up, and their crewmates at the International Space Station have closed the hatches between their airlock and the rest of the space station, and begun depressurizing the airlock. Watch it LIVE on NASA TV.

The spacewalkers will likely begin their spacewalk earlier than its planned 3:16 a.m. EDT (0716 GMT) starting time.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- Astronauts Greg Chamitoff and Drew Feustel are still suiting up in preparation to begin their spacewalk at 3:16 a.m. EDT (0716 GMT). Watch it LIVE on NASA TV.

Other Endeavour astronauts, including commander Mark Kelly and mission specialist Mike Fincke, are assisting the spacewalkers in getting ready.

Today's spacewalk is scheduled to last six and a half hours.

-- Clara Moskowitz (@ClaraMoskowitz)

Endeavour shuttle astronauts Andrew Feustel and Greg Chamitoff are donning their NASA-issue spacesuits in preparation for today's spacewalk outside the International Space Station. Watch it LIVE on NASA TV.

The spacewalk is expected to begin at 3:16 a.m. and last six to six and a half hours.

-- Tariq Malik (@tariqjmalik)

HOUSTON -- The six astronauts aboard the space shuttle Endeavour woke at 10:30 p.m. EDT (0230 GMT Friday) to a song written by two Kennedy Space Center workers in honor of the space shuttle program, played especially for mission specialist Mike Fincke. Watch it LIVE on NASA TV.

"Thanks, that's a great song," Fincke said. "It was written by my friends Dan Keenan and Kenny McLaughlin. They work on the thermal protection system team, and it's a tribute to all the workers on Endeavour and her sister shuttles. So to all of our friends, we salute you, at Kennedy Space Center from the crew of Endeavour."

The astronauts will focus today on completing the first of four six and a half hour spacewalks scheduled for the mission. Today it will be mission specialists Greg Chamitoff and Drew Feustel working outside the International Space Station.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON-- Astronauts finished attaching the Alpha Magnetic Spectrometer to the space station at 5:46 a.m. EDT. Watch it LIVE on NASA TV.

It will spend at least the next 10 years attached to the station's starboard-side truss studying the mysteries of the universe. Read more here.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- The robotic arm of the space shuttle Endeavour has relinquished the Alpha Magnetic Spectrometer to the International Space Station's robotic arm, which will complete the job of transferring the experiment over to its permanent home on the station's truss. Watch it LIVE on NASA TV.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- Astronauts controlling the space shuttle Endeavour's robotic arm have lifted the Alpha Magnetic Spectrometer experiment out of the shuttle's payload bay in preparation to move it over to its permanent location on the International Space Station.  Watch it LIVE on NASA TV.

Soon the shuttle arm will hand off the AMS to the space station's robotic arm.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- Astronauts have grabbed an expensive astrophysics experiment called the Alpha Magnetic Spectrometer (AMS) with the space shuttle's robotic arm in preparation to lift the apparatus out of shuttle Endeavour's payload bay.

The astronauts will then transfer the AMS to the space station's robotic arm, which in turn will slowly maneuver the experiment into place to be installed on the station's backbone-like truss.

-- Clara Moskowitz (@ClaraMoskowitz)

Astronauts on shuttle Endeavour received their morning wake up music a bit late for their fourth mission day, but enjoyed the tune - especially since it was custom-made for their spaceflight.

Mission Control played the song, called "Luna," for the shuttle crew about 40 minutes late due to communications dropout that occured during the planned wake-up time at 10:56 p.m. ET. The song was performed by Jose Serrano, a friend of Endeavour astronaut Greg Chamitoff.

"That song was made especially for our flight," Chamitoff told Mission Control. He added that the entire Endeavour is crew is eager to install the station's new Alpha Magnetic Spectrometer today. "We've got a lot of good work to do today and we're raring to go."

The maneuver to transfer AMS from shuttle to station is set to begin at 1:56 a.m. EDT (0556 GMT) on Thursday, and complete at 3:41 a.m. EDT (0741 GMT).

-- Tariq Malik (@tariqjmalik)

Endeavour's six astronauts have officially begun their first full day at the International Space Station, with Mission Control radioing up a hearty "Good Morning" at 10:56 p.m. EDT (0256 May 19 GMT). Watch it LIVE on NASA TV.

Because of a communications dropout, the traditional wake up music piped up by Mission Control will be delayed by about 40 minutes, NASA officials said. But that won't keep the crew from starting their day. The alarm clocks will ring with or without the wake up call.

The big chore today will be the installation of the station's new Alpha Magnetic Spectrometer, a $2 billion experiment aimed at studying the invisible universe.

Today is Flight Day 4 of Endeavour's 16-day STS-134 mission to the International Space Station.

-- Tariq Malik (@tariqjmalik)

HOUSTON -- Astronauts have officially installed the Express Logistics Carrier 3 (ELC 3) on the International Space Station's Port 3 truss segment. The platform contains extra ammonia coolant, antenna equipment, and parts for the station's Dextre robot. Watch it LIVE on NASA TV.

"With ELC 3 installed, we now have enough spare equipment on the station to keep it running smoothly for years after the shuttle retires," shuttle astronaut Greg Chamitoff said.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON - Astronauts have now transferred a platform full of spare supplies to its intended storage location on the International Space Station's backbone-like truss. Watch it LIVE on NASA TV.

With the platform, called the Express Logistics Carrier, in place, astronauts will now secure it with an attachment mechanism.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- Astronauts aboard the space shuttle Endeavour, now docked at the International Space Station, have removed a large platform of backup supplies for the space station that was brought up inside the shuttle's payload bay. Watch it LIVE on NASA TV.

Crewmembers grabbed the platform, called the Express Logistics Carrier, with the shuttle's robotic arm and lifted it out of the payload bay. They have now passed it over to the space station's robotic arm, which will then install it on the exterior of the orbiting laboratory.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- The six astronauts aboard space shuttle Endeavour floated through the newly opened hatches between their orbiter and the International Space Station around 8:12 a.m. EDT (1212 GMT) today. Watch it LIVE on NASA TV.

"It's good to be back. It looks pretty much the same," said shuttle commander Mark Kelly as he saw the space station.

The crews will now go over safety procedures before settling into the now-crowded orbiting laboratory.

-- Clara Moskowitz (@ClaraMoskowitz)

The hatches between the space shuttle Endeavour and the International Space Station were opened at 7:38 a.m. EDT. Watch it LIVE on NASA TV.

"Hey! Welcome, welcome!" space station astronaut Paolo Nespoli called to the shuttle crew.

With the arrival of Endeavour's STS-134 crew, the population of the space station is now doubled. Shuttle commander Mark Kelly, pilot Greg Johnson, and mission specialists Michael Fincke, Greg Chamitoff, Andrew Feustel and Roberto Vittori will join the six astronauts onboard the station: Expedition 27 Russian cosmonaut and station commander Dmitry Kondratyev, NASA astronauts Ron Garan and Cady Coleman, Italian astronaut Paolo Nespoli and Russian cosmonauts Alexander Samokutyaev and Andrey Borisenko.

-- Denise Chow (@denisechow)

HOUSTON -- The space shuttle and space station crews are conducting leak checks to make sure the seals are tight between their two spacecraft before they open the hatches. Watch it LIVE on NASA TV.

Meanwhile, shuttle astronauts are also reviewing data from preliminary tests of a new system to assist with docking called STORRM (Sensor Test for Orion RelNav Risk Mitigation). The system includes cameras and sensor technologies to make future spacecraft docking easier and safer.

Endeavour astronauts turned on the system today during the docking activities, though the real test will come later in the mission after the shuttle departs from the space station and makes another pass near the outpost for the purpose of trying out the equipment.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON – The space shuttle Endeavour has successfully docked with the International Space Station. The crews will now spend about two hours checking for leaks between the two spacecraft before they open the hatches at 8:36 a.m. EDT (1236 GMT). Watch it LIVE on NASA TV.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- The space shuttle Endeavour was given a "Go" by Mission Control to proceed with docking at the International Space Staiton. Watch it LIVE on NASA TV.

Endeavour is now within 300 feet of the station. The two spacecraft are expected to connect at 6:15 a.m. EDT (1015 GMT).

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- The shuttle Endeavour performed a backflip in space called the Rendezvous Pitch Maneuver, which allowed astronauts aboard the International Space Station to take detailed photos of the orbiter's underbelly. Watch it LIVE on NASA TV.

The images will be downlinked to mission control to be analyzed for signs of any damage to Endeavour's heat shield tiles. These tiles protect the orbiter from the fiery temperatures experienced during re-entry to Earth.

Now Endeavour's commander Mark Kelly will fly the shuttle from its position 600 feet below the space station to the docking port on the station's Harmony module.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- The astronauts aboard the space shuttle Endeavour are within a mile of the International Space Station, and have spied their destination. Watch it LIVE on NASA TV.

"We're tally ho with the station!" called out Endeavour's commander Mark Kelly, indicating he could see the station for the first time.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- The space shuttle Endeavour is now about 16,000 feet, or 3 miles, away from the International Space Station, and closing in at about 10.5 mph.

When the orbiter gets even closer, it will turn a backflip to allow astronauts onboard the ISS to snap detailed photos of its underbelly to check for any damage. Watch it LIVE on NASA TV.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- The astronauts onboard space shuttle Endeavour have burned one of their orbital maneuvering systems engines in a maneuver called the terminal initiation, or TI, burn. The burn helps set the orbiter on a path for docking at the International Space Station.

The burn lasted 10 seconds and altered Endeavour's orbital speed and altitude slightly to put it on an interception course for the orbiting outpost. Watch it LIVE on NASA TV.

"Good burn, Endeavour," mission control radioed to the astronauts.

"Roger, good burn," a crewmember called back.

-- Clara Moskowitz (@ClaraMoskowitz)

HOUSTON -- The space shuttle Endeavour is nearing the International Space Station, where it will spend the remainder of its 16-day mission. The next major milestone is an engine burn called the terminal initiation burn, or TI burn. Watch it LIVE on NASA TV.

"The preliminary targets for the TI burn look good," the NASA commentator said.

-- Clara Moskowitz (@ClaraMoskowitz)

The six astronauts aboard NASA's shuttle Endeavour have officially begun their rendevous operations for today's plannned 6:16 a.m. ET (1016 GMT) docking at the International Space Station. Watch it LIVE on NASA TV.

Here's a look at today's docking activities in space (all times in Eastern Daylight Time):

12:36 AM: Rendezvous Operations Begin

03:37 AM: Terminal Initiation Burn

06:16 AM: Docking with ISS

08:36 AM: Hatch Opening and Welcome Ceremony

09:00 AM: Mission Status Briefing

-- Tariq Malik (@tariqjmalik)

The six astronauts aboard NASA's shuttle Endeavour have officially begun their rendevous operations for today's plannned 6:16 a.m. ET (1016 GMT) docking at the International Space Station. Watch it LIVE on NASA TV.

Here's a look at today's docking activities in space (all times in Eastern Daylight Time):

12:36 AM: Rendezvous Operations Begin

03:37 AM: Terminal Initiation Burn

06:16 AM: Docking with ISS

08:36 AM:Hatch Opening and Welcome Ceremony

09:00 AM

-- Tariq Malik (@tariqjmalik)

It's docking day for the crew of shuttle Endeavour as the orbiter closes in on the International Space Station. Docking is set for 6:15 a.m. EDT (1015 GMT). Watch it LIVE on NASA TV.

Mission Control roused Endeavour's crew today at 10:56 p.m. EDT (0256 May 18 GMT) with the song "Drops of Jupiter" by the band Train, a tune selected for the shuttle's pilot Gregory H. Johnson by his family.

"I love that song and I love being in space," Johnson radioed Mission Control.

The song is a favorite of Johnson's son Matt, who will celebrate a birthday tomorrow.

"Matt, happy birthday tomorrow, sorry I missed that one but we'll catch up. And I want to say that's a perfect way to start an exciting rendezvous day!" Johnson said.

Today is Flight Day 3 of Endeavour's 16-day mission to the space station.

-- Tariq Malik (@tariqjmalik)

Endeavour's astronauts are wrapping up their survey of the shuttle's heat shield tiles to look for any damage from yesterday's launch. Watch it LIVE on NASA TV.

The main focus of the inspection is on the wing-leading edges and nosecap of the orbiter, which are the areas that experience the hottest temperatures when the shuttle re-enters Earth's atmosphere during landing, according to NASA officials. The astronauts use the shuttle's robotic arm to scan the underbelly, sides and nosecap of Endeavour, which gives them an extra 50 fee4t (15 meters) of reach.

Next, the astronauts will berth the shuttle's robotic arm and continue with preparations to transfer cargo from Endeavour's middeck once it is reaches the International space Station.

-- Denise Chow (@denisechow)

CAPE CANAVERAL, Fla. -- The astronauts aboard the space shuttle Endeavour have begun scanning their orbiter's sensitive heat shield tiles with a 50-foot (15 meter) sensor-tipped boom attached to the shuttle's robotic arm. Watch it LIVE on NASA TV.

The scan is a routine procedure for the day after a launch to make sure the shuttle didn't suffer any damage from falling debris during its liftoff.

The astronauts will take more than five hours to scan both wings and the underbelly of the shuttle.

-- Clara Moskowitz (@ClaraMoskowitz)

CAPE CANAVERAL, Fla. -- The space shuttle Endeavour's crew awoke this morning at 11:56 p.m. EDT (0356 GMT) to the song "Beautiful Day" by U2, a tune picked for commander Mark Kelly by his wife, Congresswoman Gabrielle Giffords, and his daughters Claudia and Claire. Watch it LIVE on NASA TV.

"It's good to be waking up in space again," Kelly said. "I want to thank Gabby, Claudia and Claire for that great wakeup song. It's always good to hear. Here's to a beautiful day in space!"

The song was familiar, as Giffords had also chosen it to wake up Kelly and his crewmates during the July 2006 STS-121 space shuttle mission. Kelly and Giffords were dating at the time; the married in November 2007.

Giffords, who is recovering from an assassination attempt in January, was on hand here at Kennedy Space Center to watch Kelly and his crew launch into space.

The astronauts are beginning a busy 16-day mission to the International Space Station. On tap for today: a detailed scan of their orbiter's heat shield to make sure it wasn't damaged during launch.

-- Clara Moskowitz (@ClaraMoskowitz)

CAPE CANAVERAL, Fla. – The five engines boosting Endeavour and its external tank towards orbit have shut down as planned about eight and a half minutes into flight. Watch it LIVE on NASA TV.

The milestone is known as Main Engine Cut Off (MECO). The spacecraft is flying toward its intended orbit, with the next major task aimed at discarding the shuttle’s external tank.

-- Clara Moskowitz (@ClaraMoskowitz)

CAPE CANAVERAL, Fla. – The twin solid rocket boosters assisting Endeavour’s launch into space have separated as planned from the shuttle’s external tank. Watch it LIVE on NASA TV.

The reusable boosters separated about two minutes and five seconds after liftoff and fell back toward the Atlantic Ocean, where they will land under parachutes and be retrieved by recovery ships. They are equipped with cameras to record the performance of Endeavour’s external tank and any foam loss seen during today’s ascent. 

-- Clara Moskowitz (@ClaraMoskowitz)

CAPE CANAVERAL, Fla. – The space shuttle Endeavour has cleared the launch tower and is gaining altitude after lifting off at about 8:56 a.m. EDT (1256 GMT). Watch it LIVE on NASA TV.

Riding spaceward aboard Endeavour are STS-134 commander Mark Kelly, pilot Gregory H. Johnson and mission specialists Mike Fincke, Greg Chamitoff, Andrew Feustel, and European Space Agency astronaut Roberto Vittori. It should take Endeavour about 8 1/2 minutes to ferry its six-astronaut crew into orbit. 

-- Clara Moskowitz (@ClaraMoskowitz)

CAPE CANAVERAL, Fla. - Mission managers have conducted a final "go/no-go" poll and decided unanimously to launch the space shuttle Endeavour this morning at 8:56 a.m. EDT (1256 GMT). The weather remains "green" for Endeavour to blast off, beginning its final climb to orbit. Watch it LIVE on NASA TV.

"Looks like a great day to launch Endeavour for the final time," launch director Mike Leinbach told the crew.

-- Clara Moskowitz (@ClaraMoskowitz)

Clouds over NASA's Florida spaceport are expected to scatter within the next 30 minutes, ahead of Endeavour's scheduled launch at 8:56 a.m. EDT, NASA officials said. Watch it LIVE on NASA TV.

"A cloud layer over KSC is expected to scatter before Endeavour's 8:56a ET launch and not be a concern," agency officials said via Twitter. Current weather conditions remain acceptable for this morning's launch.

The countdown clock has resumed ticking down the minutes and seconds to liftoff. The next milestone will be a 40-minute hold at the T minus 9 minute mark, during which time a series of polls will be conducted to confirm the launch readiness of the various stations.

-- Denise Chow (@denisechow)

Engineers successfully repaired a damaged tile around Endeavour's crew hatch, covering the small area with a mixture used for minor fixes to shuttle heat shield tiles. Watch it LIVE on NASA TV.

"The small area of damaged tile has been repaired & the issue will not constrain launch. A slurry was used to coat the area," NASA officials said via Twitter.

Launch preparations are continuing toward a scheduled liftoff at 8:56 a.m. EDT.

-- Denise Chow (@denisechow)

Ground crews are investigating some tile damage found on the orbiter around the crew hatch, according to NASA officials. Engineering discussions are underway, as Endeavour sits on the launch pad, roughly two hours away from its scheduled liftoff. Watch it LIVE on NASA TV.

The damaged tile is located around the crew hatch, and appears to be one that was previously repaired, said NASA spokesman George Diller. The countdown is proceeding as engineers attempt to make repairs to the small area.

-- Denise Chow (@denisechow)

The six astronauts who will fly Endeavour on its final mission have boarded their vehicle in preparation for launch. Commander Mark Kelly was the first to climb aboard Endeavour, followed by pilot Greg Johnson and mission specialists Greg Chamitoff, Mike Fincke and Drew Feustel. Italian astronaut Roberto Vittori was the last to be strapped into his seat, and the crew hatch is scheduled to be closed at 6:56 a.m. EDT. Watch it LIVE on NASA TV.

Countdown preparations remain on track toward Endeavour's launch at 8:56 a.m. EDT.

-- Denise Chow (@denisechow)

Endeavour's six astronauts departed their crew quarters and boarded the "Astro Van" at 5:11 a.m. EDT. The crew smiled and waved to the cheering crowd as they exited the Operations & Checkout building. Watch it LIVE on NASA TV.

The astronauts are now making the roughly 10 mile journey to the seaside Launch Pad 39A, where final preparations are underway for this morning's launch at 8:56 a.m. EDT.

At the pad, the astronauts will begin boarding Endeavour one by one, starting with commander Mark Kelly at 5:41 a.m. EDT. The crew hatch is scheduled to be sealed at 6:56 a.m. EDT.

Forecasts continue to show a 70 percent chance of favorable weather for today's launch. No technical issues are being worked at this time, NASA officials said.

-- Denise Chow (@denisechow)

The six astronauts of Endeavour's STS-134 flight are donning their bright orange launch-and-entry pressure suits. Commander Mark Kelly, pilot Greg H. Johnson, and mission specialists Michael Fincke, Andrew Feustel, Greg Chamitoff, and Italian astronaut Roberto Vittori will then leave the Operations & Checkout building at Kennedy Space Center and travel to Launch Pad 39A. Watch it LIVE on NASA TV.

-- Denise Chow (@denisechow)

CAPE CANAVERAL, Fla. – The weather forecast for this morning's planned launch of the shuttle Endeavour is hopeful, with a 70 percent chance of good conditions still predicted. Watch it LIVE on NASA TV.

"Everything right now is looking really good for an on-time launch," said shuttle weather officer Patrick Barrett, a Lieutenant Colonel in the 45th Weather Squadron. "The winds have decreased quite significantly. We do have a slight chance of seeing some clouds come in, but it looks pretty good that the clouds will hold off. As long as things remain as they are right now things remain very favorable."

-- Clara Moskowitz (@ClaraMoskowitz)

CAPE CANAVERAL, Fla. – NASA is still working under a planned hold in the launch countdown at T minus three hours. Preparations for liftoff today are continuing, with no issues at the moment looking to prevent a launch at 8:56 a.m. EDT.

Watch it LIVE on NASA TV.

The weather forecast is still an optimistic 70 percent chance of good conditions for launch, with just a small chance of clouds or too-strong winds interfering.

-- Clara Moskowitz (@ClaraMoskowitz)

CAPE CANAVERAL, Fla. -- Space shuttle Endeavour's fuel tank is fully loaded and now in a state called "stable replenish," when only the small amounts of super-cold liquid hydrogen and liquid oxygen that boil off over time are refilled as needed. Watch it LIVE on NASA TV.

The countdown has reached a scheduled hold at at T minus three hours.

-- Clara Moskowitz (@ClaraMoskowitz)

CAPE CANAVERAL, Fla. -- The process of filling shuttle Endeavour's external fuel tank with super-chilled propellants is more than halfway complete. It takes roughly three hours to load the organge tank with more than 500,000 gallons of liquid oxygen and liquid hydrogen fuel.  Watch it LIVE on NASA TV.

Tanking should be complete around 2:35 a.m. EDT (0635 GMT).

The launch team is not working any issues that could prevent liftoff today at 8:56 a.m. EDT (1356 GMT).

-- Clara Moskowitz (@ClaraMoskowitz)

CAPE CANAVERAL, Fla. -- NASA has begun loading the shuttle Endeavour's external fuel tank with its super-cold liquid oxygen and liquid hydrogen propellants in preparation for launch tomorrow. Watch it LIVE on NASA TV.

It will take approximately three hours to load 535,000 gallons of fuel into Endeavour's 150-foot tall orange external tank.

"Launch teams are not working any issues right now that would prevent us from launching on time," NASA commentator Allard Beutel said.

There is still a 70 percent chance of good weather predicted for the shuttle's scheduled 8:56 a.m. EDT liftoff.

-- Clara Moskowitz (@ClaraMoskowitz)

CAPE CANAVERAL, Fla. -- The countdown is proceeding here at Kennedy Space Center toward launching the space shuttle Endeavour on Monday at 8:56 a.m. EDT (1256 GMT). Today at noon EDT (1600 GMT) the shuttle's metal protective scaffolding, called the Rotating Service Structure, was rolled away from Endeavour in preparation for liftoff.

Endeavour's six-man crew will spend today reviewing their mission plans, meeting with mission managers, and resting up before going to bed at 4 p.m. EDT (2000 GMT) in preparation for their morning liftoff on Monday.

-- Clara Moskowitz (@ClaraMoskowitz)

Ground teams at NASA's Kennedy Space Center in Florida are continuing with preparations for Endeavour's next scheduled launch attempt on Monday (May 16).

Yesterday, NASA resumed the countdown clock toward Monday's liftoff at 8:56 a.m. (1256 GMT).

This second launch attempt comes after a two-week delay, during which time technicians repaired the broken switchbox that caused a power glitch on April 29. 

Current forecasts show a 70 percent chance of acceptable conditions a launch time, according to NASA officials.

-- Denise Chow (@denisechow)

CAPE CANAVERAL -- NASA engineers gained access today (April 30) to the area on the shuttle responsible for Friday's launch cancellation: two failed heaters on an auxiliary power unit. The heaters were discovered to be broken during yesterday's launch countdown, forcing NASA to call a scrub.

On Saturday, workers tested various systems to determine the cause of the problem, but no smoking gun has yet been found. NASA cannot determine a new launch date until the severity of the problem is determined and a fix put in place.

"Managers are not expected to decide until Sunday morning, at the earliest, whether a launch attempt on Monday is possible," according to a NASA statement.

The next possible launch opportunity for the shuttle Endeavour is Monday, May 2 at 2:44 p.m. EDT (1844 GMT).

-- Clara Moskowitz (@ClaraMoskowitz)

CAPE CANAVERAL, Fla. – Shuttle launch director Mike Leinbach just announced that the next launch attempt for shuttle Endeavour will be no earlier than Monday afternoon, May 2nd as the launch team begins working toward a 72-hour scrub turnaround.

Engineers believe that there is an electrical short in a controller box that supplies power to a pair of heaters on one of Endeavour’s APU’s or Auxiliary Power Units. These units are critical for launch as they provide the hydraulic power to the Orbiter including the ability to swivel or 'gimbal' the three main engines, deploy the landing gear and control the vehicle’s aerosurfaces during re-entry and landing.

Mr. Leinbach noted that the problem area is located deep within Endeavour’s aft compartment and that it will take a significant amount of time to install the scaffolding needed to access the Load Control Assembly unit for troubleshooting and possible repair. The shuttle’s massive External Tank is now being drained of liquid hydrogen and liquid oxygen in order to ‘safe’ the vehicle before technicians can gain access to the Orbiter.

-- Roger Guillemette

CAPE CANAVERAL, Fla. – A problem with heaters on one of Endeavour's Auxiliary Power Units has forced NASA officials to scrub today's launch attempt. These units are critical for launch as they provide the hydraulic pressure to the Orbiter including the ability to swivel or 'gimbal' the three main engines.

Watch the action LIVE on NASA TV.

A troubleshooting team will investigate the cause and repair options. The earliest Endeavour could be readied for a new launch attempt would be in 48 hours, on Sunday May 1st.

-- Roger Guillemette

CAPE CANAVERAL, Fla. – The crew of space shuttle Endeavour, clad in their bright orange launch-and-entry pressure suits, has departed the Operations & Checkout (O&C) Building at the Kennedy Space Center. The six astronauts, riding in their silver 'Astro Van', are now en route to seaside pad 39A where the shuttle is poised for launch, framed against a cloudy sky with hints of blue peeking thru.

Watch the action LIVE on NASA TV.

After a 25-minute ride to the launch pad, the STS-134 astronauts, all spaceflight veterans, will enter Endeavour one by one, beginning with mission commander Mark Kelly, to prepare for this afternoon's launch attempt.

Endeavour's launch is scheduled for 3:47:55 p.m. EST (1947:55 GMT). The launch team is not working any technical issues and the countdown so far has been smooth and uneventful. The official weather forecast is an optimistic 70% chance of acceptable conditions for launch – the concerns for launch are a potential low cloud ceiling and crosswinds out of limits at the Shuttle Landing Facility (SLF). There is also a concern that all 3 Trans-Oceanic Abort Landing (TAL) sites may be No-Go to support a launch; at least one TAL must be available to support an emergency landing.

Crowds of spectators are pouring into the communities surrounding KSC to witness Endeavour's final launch; at 10 a.m. EDT, the shores of the SR-528 causeway connecting Cape Canaveral and Merritt Island were maxed-out with vehicles and launch spectators, five hours before liftoff.

-- Roger Guillemette

CAPE CANAVERAL, Fla. -- The countdown toward this afternoon's space shuttle launch is proceeding smoothly, and the launch team is not working on any issues at the moment. The weather forecast is still a hopeful 70 percent chance of good conditions, with the only risks being a cloud ceiling and strong winds that could foil the launch. Watch the action LIVE on NASA TV.

The countdown has entered a planned 2.5-hour hold at T-3 hours.

-- Clara Moskowitz (@ClaraMoskowitz)

NASA has finished loading super-cold liquid hydrogen and liquid oxygen fuel into space shuttle Endeavour's orange external fuel tank in preparation for launch this afternoon at 3:47 p.m. EDT (1947 GMT). The countdown is proceeding smoothly, and the weather forecast is still 70 percent "go" for liftoff today. Watch the action LIVE on NASA TV.

"We're all very optimistic that it will cooperate later today," Pete Nickolenko, NASA's assistant launch director, said of the weather on NASA TV.

-- Clara Moskowitz (@ClaraMoskowitz)

About three hours into tanking Endeavour for today's 3:47 p.m. EDT launch, engineers think they've fixed an issue in the shuttle's right Orbital Maneuvering Systems (OMS) engine pod. The pod's fuel tank had slightly high pressure of liquid oxygen fuel. Engineers were able to open a valve between the right and left fuel tanks to resolve the problem.LIVE on NASA TV.

"The issue apparently has been corrected," NASA spokesman Allard Beutel said.

-- Clara Moskowitz (@ClaraMoskowitz)

CAPE CANAVERAL, Fla. -- NASA began loading the shuttle Endeavour's external fuel tank with its cryogenic liquid oxygen and liquid hydrogen propellants this morning at 6:22 a.m. EDT (1022 GMT). Watch the action LIVE on NASA TV.

The shuttle is still on track to launch today at 3:47 p.m. EDT (1947 GMT). The weather forecast remains at a 70 percent chance of good conditions for launch.

-- Clara Moskowitz (@ClaraMoskowitz)

CAPE CANAVERAL, Fla. -- The protective metal structure surrounding the space shuttle Endeavour has been rolled back in preparation for launch tomorrow.

NASA plans to lift off Endeavour Friday (April 29) at 3:47 p.m. EDT (1947 GMT). The retraction of the protective shroud was delayed several hours due to severe thunder storms moving over the launch pad. The delay should have no impact to tomorrow's launch timeline, NASA says.

-- Clara Moskowitz (@ClaraMoskowitz)

CAPE CANAVERAL, Fla. -- NASA has reduced the chances of good weather for Friday's planned liftoff of the space shuttle Endeavour from 80 percent to 70 percent. Crosswinds and a cloud front threaten to linger in the area over the launch pad here at Kennedy Space Center, postponing the launch.

On this last day before launch day, Endeavour's six-man crew has a relatively light day, with a weather briefing, a briefing on the status of the shuttle's payload, and a trip out to the launch pad for the four mission specialists to inspect Endeavour. The astronauts will all have some free time to spend with their families as well.

-- Clara Moskowitz (@ClaraMoskowitz)

CAPE CANAVERAL, Fla. -- As NASA workers prepare the space shuttle Endeavour for its last launch on Friday, a notable guest arrived today. Congresswoman Gabrielle Giffords, wife of Endeavour's commander Mark Kelly, arrived at the Florida spaceport this afternoon, according to her Twitter feed. Watch the action LIVE on NASA TV.

"Gabrielle arrived in Fla. The excitement of the #Endeavour launch is in the air," read the tweet.

Endeavour is slated to lift off Friday (April 29) at 3:47 p.m. EDT (1947 GMT) on a two-week trip to the International Space Station.

-- Clara Moskowitz (@ClaraMoskowitz)

CAPE CANAVERAL, Fla. -- NASA picked up the countdown toward the planned liftoff of space shuttle Endeavour on Friday (April 29). The countdown began at the T-43 hour mark at 2 p.m. EDT (1800 GMT). Watch the action LIVE on NASA TV.

Endeavour's STS-134 crew, led by commander Mark Kelly, arrived here at Kennedy Space Center at 12:52 p.m. EDT (1852 GMT).

-- Clara Moskowitz (@ClaraMoskowitz)