Personal: Male, Married, One child. Born in Phoenix, Arizona, USA.

Astronaut Career

Astronaut Group: NASA Group 14 - 1992. Active Entered space service: 31 March 1992. Number of Flights: 4.00. Total Time: 40.01 days. Number of EVAs: 7.00. Total EVA Time: 2.07 days.

NAME: Steven L. Smith

NASA Astronaut

PERSONAL DATA:

Born December 30, 1958, in Phoenix, Arizona, but considers San Jose, California, to be his hometown. Married. He enjoys flying, scuba diving, basketball, camping, and traveling.

EDUCATION:

Graduated from Leland High School, San Jose, California, in 1977; received a bachelor of science degree in electrical engineering from Stanford University in 1981; a master of science degree in electrical engineering from Stanford University in 1982; and a master's degree in business administration from Stanford University in 1987.

SPECIAL HONORS:

NASA Space Flight Medal, NASA Performance Award for Excellence, IBM Outstanding Technical Achievement Award, IBM Outstanding Community Service Award. Seven-time high school and collegiate All-American in swimming and water polo. Two-time National Collegiate Athletic Association (NCAA) Champion at Stanford in water polo. Captain of the 1980 NCAA Championship team.

EXPERIENCE:

Steve Smith worked for IBM in the Large Scale Integration (semiconductor) Technology Group in San Jose as a technical group lead from 1982 until 1985. During that time, he was responsible for the development of electron beam chemical and lithographic processes. Following a leave to pursue graduate studies, Smith returned to IBM's Hardware and Systems Management Group in Santa Clara as a product manager for voice and telephony products until 1989.

NASA EXPERIENCE:

Steve Smith is a veteran of two space flights covering 8.8 million miles and three space walks totaling 19 hours. He joined NASA in 1989 in the Payload Operations Branch, Mission Operations Directorate. As a payload officer, his duties included preflight payload integration and real-time flight controller support in Mission Control. Preflight integration activities included Shuttle/payload integrated operations development, crew procedures development, and spacecraft design review. Smith supported STS-31, STS-37, STS-48, and STS-49 from Mission Control. He was selected as an astronaut candidate by NASA in March 1992 and reported for training in August 1992.

In August 1993, Smith completed one year of astronaut candidate training. He served as the Astronaut Office representative for the Space Shuttle main engines, the solid rocket boosters, the external tank, and Shuttle safety from April to November 1993. In September 1993, Smith became the first member of the 1992 astronaut class to receive a flight assignment.

Smith served as a mission specialist aboard the Space Shuttle Endeavour on Mission STS-68, September 30 to October 11, 1994. Smith's responsibilities were split between Shuttle systems, Space Radar Lab 2 (SRL-2, the flight's primary payload), and several experiments located in the crew cabin. Smith was one of two crewmen trained to perform a space walk had one been required. As part of NASA's Mission to Planet Earth, SRL-2 studied the Earth's surface and atmosphere, creating radar images of the Earth's surface environment and mapping global carbon monoxide pollution. Endeavour circled Earth 183 times and traveled 4.7 million miles during the 11 day, 5 hour and 46 minute flight.

From November 1994 until March 1996, Smith was assigned to duties at the Kennedy Space Center as a member of the astronaut support team. The team was responsible for Space Shuttle prelaunch vehicle checkout, crew ingress and strap-in prior to launch, and crew egress post landing.

Smith performed three space walks as a member of the February 1997 STS-82 Discovery crew which serviced the Hubble Space Telescope (HST). The crew completed five space walks in order to dramatically improve the scientific capability of the telescope and to replace degraded support equipment. HST's orbit was also increased 8 miles by the crew. The flight orbited the Earth 150 times covering 4.1 million miles in 9 days, 23 hours, 37 minutes and Smith's three space walks totaled 19 hours, 10 minutes.

• 30 September 1994 Flight: STS-68. Flight Up: STS-68. Flight Back: STS-68. Flight Time: 11.24 days.

• 11 February 1997 Flight: STS-82. Flight Up: STS-82. Flight Back: STS-82. Flight Time: 9.98 days.

• 20 December 1999 Flight: STS-103. Flight Up: STS-103. Flight Back: STS-103. Flight Time: 7.97 days.

• 8 April 2002 Flight: STS-110. Flight Up: STS-110. Flight Back: STS-110. Flight Time: 10.82 days.

5 December 1992 - NASA Astronaut Training Group 14 selected.. The group was selected to provide pilot, engineer, and scientist astronauts for space shuttle flights.. Qualifications: Pilots: Bachelor's degree in engineering, biological science, physical science or mathematics. Advanced degree desirable. At least 1,000 flight-hours of pilot-in-command time. Flight test experience desirable. Excellent health. Vision minimum 20/50 uncorrected, correctable to 20/20 vision; maximum sitting blood pressure 140/90. Height between 163 and 193 cm.

Mission Specialists: Bachelor's degree in engineering, biological science, physical science or mathematics and minimum three years of related experience or an advanced degree. Vision minimum 20/150 uncorrected, correctable to 20/20. Maximum sitting blood pressure of 140/90. Height between 150 and 193 cm.. Four pilots and 15 mission specialists, nine civilians and ten military. Chosen from 2054 applicants, 87 of which screened in December 1991/January 1992. Five additional international astronauts.

The Hubble Space Telescope was released back into orbit at 06:41 GMT on February 19. Discovery landed on Runway 15 at Kennedy Space Center at 08:32 GMT on February 21.

Under clear and starry skies at the Kennedy Space Center, Discovery lifted off on time at 6:50 p.m. Central time, lighting up the Central Florida coastline, to send Commander Curt Brown, Pilot Scott Kelly, and Mission Specialists Steve Smith, Jean-Francois Clervoy, John Grunsfeld, Mike Foale and Claude Nicollier on a two-day chase to catch up to and retrieve the 12 and a half ton telescope. Hubble was sailing over Eastern Africa at the time of launch.

Eight and a half minutes after the third and final shuttle launch of the year, Discovery was in orbit as its crew members began to configure shuttle systems for the planned 8-day mission. One rendezvous burn of the reaction control system jets is planned before the crew goes to sleep early Monday to fine tune Discovery's path to catch up to Hubble.

Technically, Hubble has been in hibernation since the loss of a fourth gyroscope on November 13 designed to enable the telescope to point precisely at distant astronomical targets for scientific observations. Hubble is in what is known as "safe mode", a state of dormancy in which the telescope aims itself constantly at the sun to provide electrical power to its systems. Hubble is scheduled to be captured by Discovery's robot arm around 6:40 p.m. Central time Tuesday.

Once the crew retrieves Hubble, it will be parked at the rear of Discovery's cargo bay so that two teams of space-walking astronauts can perform repairs and upgrades to its systems during three nights of space walks. The most vital of the space walks will occur on Wednesday night, when Smith and Grunsfeld replace all six of Hubble's gyroscopes and install devices to improve voltage regulation to the telescope's systems. Only three space walks are planned because the mission was shortened. Smith and Grunsfeld will conduct the first and third space walks, while the second will be conducted by Foale and Nicollier.

If all goes as planned, Hubble will be released back into orbit on Christmas Day around 5 p.m. Central time, with landing planned on Dec. 27 at 4:24 p.m.. Central time at the Kennedy Space Center.

The astronauts are scheduled to begin an eight-hour sleep period at 1:50 a.m. Central time Monday and will be awakened at 9:50 a.m. Central time to begin their first full day in orbit.

Discovery is orbiting the Earth at an altitude of about 300 nautical miles, completing one orbit of the Earth every 90 minutes.

• Bay 1-2: External airlock/ODS
• Bay 7-8: ORU Carrier (Spacelab pallet). Carried Hubble replacement spares arranged as follows: COPE protective enclosure with three RSU gyros, a new solid state recorder, and an S-band transmitter; LOPE enclosure with an HST-486 computer and voltage improvement kit; ASIPE enclosure with a spare HST-486 and spare RSU; FSIPE enclosure with a replacement FGS-2 fine guidance sensor; and NPE enclosure with New Outer Blanket Layer insulation.
• Bay 11: Flight Servicing System (FSS). Contained the BAPS (Berthing and Positioning System) used to dock with the aft end of the Hubble Space Telescope.
• Bay 8: APC carrier with foot restraint
• Bay 12: APC carrier with HST foot retstraint

Today will be a day of preparation for the crew, gearing up for the rendezvous and capture of HST planned for Tuesday and the three maintenance spacewalks that will follow later in the week. At about 1 p.m., European Space Agency astronaut Jean-Francois Clervoy will power up Discovery's robotic arm to check its operation. Clervoy will survey Discovery's cargo bay using television cameras on the arm, checking the condition of the equipment planned for installation on the telescope and the cradle that will hold HST during the spacewalks. While Clervoy operates the arm, Payload Commander Steve Smith and Mission Specialist John Grunsfeld will power up the payload bay HST support equipment. Later, around 6 p.m., Commander Curt Brown and Pilot Scott Kelly will check out the laptop computers, navigation aids and flight controls in Discovery's cockpit that will be used for tomorrow's encounter with HST.

Meanwhile, on Discovery's middeck, Grunsfeld, along with European astronaut Claude Nicollier, will begin a check of the four spacesuits onboard. Early in the afternoon, about 1 p.m., the crew will lower the cabin pressure aboard Discovery as part of the spacewalk preparations. This reduces the amount of time the spacewalkers must breathe oxygen as part of a standard protocol to purge nitrogen from the body prior to beginning a spacewalk.

At 8:35 p.m. CST, Brown, Smith, Clervoy and Mike Foale will take a break from their work to talk with CBS news and other television networks about their mission.

As some of their final activities today, the crew will fire Discovery's large orbital maneuvering system engines at 10:32 p.m. to slow the rate at which the Shuttle is closing on HST. A second, smaller engine firing will follow at 11:27 p.m. to further fine tune the Shuttle's approach toward Hubble. Capture of the telescope remains scheduled for 6:41 p.m. Tuesday.

Discovery is in excellent condition, orbiting Earth every 95 minutes, 27 seconds. The high point of Discovery's orbit is 363 statute miles and the low point is 298 statute miles.

Controllers at Goddard Space Flight Center had placed the space telescope in an attitude with its closed aperture pointed toward Earth. Commander Curt Brown guided Discovery through an approach from below and fly-around. Then, Mission Specialist Jean-Francois Clervoy reached out with the shuttle's robotic arm to grip a grapple fixture on Hubble. The grapple was made at 6:34 p.m. Central time, one day, 23 hours and 44 minutes after Discovery's launch from the Kennedy Space Center in Florida.

Clervoy used the arm to rotate the space telescope and bring its base into the cargo bay. Hubble, gleaming silver in its Mylar insulation flanked by golden-colored solar arrays, was firmly attached to the Flight Support System in Discovery's cargo by a little after 7:30 p.m. Hubble is as tall as a four-story building. With a maximum diameter of 14 feet, it is about the size of a railroad tank car.

The Flight Support System is a U-shaped device with a circular platform between the U's arms now supporting the space telescope. The system provides power from Discovery to the telescope and can rotate and tilt it to facilitate access to its various compartments by space-walking astronauts. An initial, carefully choreographed survey using a camera at the end of the robotic arm was made. Camera surveys of Hubble's condition will continue during the crew's sleep period, scheduled to begin about 12:50 a.m. Wednesday.

The first of three planned space walks to repair and upgrade Hubble equipment is scheduled to begin at 1:40 p.m. Wednesday, though astronauts may get an early start. If they can get ahead of schedule, they may be able to perform some tasks that had been scheduled for the cancelled fourth spacewalk.

On Wednesday, Mission Specialist and Payload Commander Steve Smith and Mission Specialist John Grunsfeld will first replace the telescope's three Rate Sensor Units. Each contains two gyroscopes. The second major task is installation of six Voltage/Temperature Improvement Kits between Hubble's solar panels and its six 10-year-old batteries. The cell telephone-sized kits are designed to prevent any overheating or overcharging of those batteries.

Discovery's systems continue to function well as the astronauts wind up final preparations for Wednesday's space walks and prepare for sleep. The spacecraft was in an orbit with a high point of 380 statute miles and a low point of 355 miles.

While the crew slept, the Shuttle continued to close in on the Hubble Space Telescope at a rate of about 125 statute miles with each 90 minute long orbit of Earth. At the time the crew woke this morning, Discovery trailed the telescope by about 330 statute miles.

The crew will fire the Shuttle's thrusters at 12:38 p.m. today to slightly raise Discovery's orbit and slow the closing rate on Hubble. Another engine firing will be conducted about 48 minutes later to further adjust the closing rate and aim Discovery to reach a point eight nautical miles behind the telescope -- the starting point for the final phase of the rendezvous -- about three hours later. Just before Discovery reaches that point, European astronaut Jean-Francois Clervoy will power up the robotic arm and lift it to a position just above its latches along the left edge of the Shuttle cargo bay.

At 4:28 p.m., Discovery will reach the starting point and fire its thrusters again to begin the final phase of rendezvous, putting the Shuttle on a course to directly intercept the telescope on the next orbit of Earth. As Discovery closes the final distance to Hubble, four small course correction engine firings will fine-tune the approach and Clervoy will raise the arm high above the payload bay, poised to latch onto the Hubble's grapple fixture.

When Discovery reaches a point about half a mile away and directly beneath the telescope, Commander Curt Brown will take over manual control of the Shuttle. Brown, assisted by Pilot Scott Kelly, will gently maneuver the 110-ton Shuttle to within 35 feet of the orbiting observatory to allow Clervoy to capture it with the arm. After the arm has latched onto the telescope, Clervoy will lower it into a cradle in the aft cargo bay. Using controls in the aft cockpit of Discovery, Payload Commander Steve Smith will then latch the telescope in place, where it will remain for the next four days. Hubble is planned to be latched into the bay at about 7 p.m. Once the telescope has been secured in the payload bay, Clervoy will release the arm and use it to perform a television survey of the Hubble's exterior.

The first of three planned Hubble maintenance spacewalks is planned to begin at 1:40 p.m. Wednesday.

Astronauts Steve Smith and John Grunsfeld are scheduled to begin the first of three planned maintenance spacewalks today at about 1:40 p.m. The crew was awakened this morning to the song "Hucklebuck" performed by Beau Jocque and the Zydeco Hi-Rollers, a tune that the spacewalkers heard many times while training hundreds of hours for the mission in the 6.5-million gallon water tank at the Johnson Space Center in Houston.

Although not scheduled to begin until 1:40 p.m., Smith and Grunsfeld could begin the planned six-hour spacewalk earlier if they complete preparations ahead of schedule. Once outside Discovery's cabin, the first task they will perform will be to replace the telescope's three Rate Sensor Units, each of which contains two gyroscopes. Of the six gyroscopes currently installed in Hubble, four have failed. At least three operable gyroscopes are needed to point the telescope with the accuracy required to track its astronomical targets.

After the rate sensor units have been installed, the two spacewalkers will then open valves on the telescope's Near Infrared Camera and Multi-Object Spectrometer to purge nitrogen coolant from that instrument in preparation for its servicing on the next Shuttle maintenance mission. Next, they will install six Voltage/Temperature Improvement Kits for the Hubble's batteries that will increase the batteries' efficiency and reduce a potential for them to overcharge and overheat. If those tasks are completed and the spacewalkers have extra time, they may perform some additional small jobs such as installing handrail covers and inspecting brackets.

While Smith and Grunsfeld are outside, inside the cabin European astronaut Jean-Francois Clervoy will control Discovery's robotic arm, maneuvering the spacewalkers into position to work on the telescope. Discovery's other spacewalking team, astronaut Mike Foale and European astronaut Claude Nicollier, also will assist from inside the cabin. Foale and Nicollier are scheduled to perform the mission's second spacewalk tomorrow. Smith and Grunsfeld are planned to again venture outside on Friday for the flight's third and final spacewalk.

Discovery remains in near-perfect condition with no mechanical problems of concern to flight controllers, as has been the case since its launch on Sunday. It is orbiting at an altitude of 380 by 365 statute miles.

Working deliberately, Smith and Grunsfeld replaced three Rate Sensor Units, each containing two gyroscopes. Four of Hubble's gyroscopes had failed, making the telescope unable to point itself precisely enough to do science since Nov. 13. At least three operable gyroscopes are needed to point the telescope with the accuracy required to track its astronomical targets.

The spacewalkers also installed Voltage/Temperature Improvement Kits on wiring from Hubble's solar arrays to each of its six batteries. The kits are designed to improve control of the charging of the space telescope's 10-year-old batteries.

With Hubble latched upright in the payload bay, Smith and Grunsfeld completed all major tasks scheduled for the first of three spacewalks on three consecutive days. A few minor objectives, including applying lubricant to the door of one of the telescope's bays and taking close-up photos of the Voltage/Temperature Improvement Kits, were left undone. Flight and telescope controllers decided to cancel the photography job and schedule the 10-minute lubrication job for Thursday's space walk. The duration of the spacewalk was second only to the 8 hour, 29 minute space walk from Endeavour on STS-49 in May 1992.

A few minor problems helped account for the length of the space walk. One of the old gyroscope-containing Rate Sensor Units was a tight fit in the box designed to protect it on its return to Earth, though eventually it was placed inside and the lid closed. Another involved opening valves and removing caps on the Near Infrared Camera and Multi-Object Spectrometer, in preparation for restoring it to operation during the next Hubble Servicing mission. That task too eventually was completed.

All in all flight and telescope controllers were delighted with the accomplishments of the day.

Major tasks on Thursday's space walk by Michael Foale and Claude Nicollier include replacement of Hubble's outmoded DF-224 computer with a more modern unit 20 times faster and with six times the memory. They also will replace one of Hubble's three fine guidance sensors, used to precisely point the telescope and gather scientific data. The astronauts also may perform "get-ahead tasks," some first scheduled for a fourth space walk. That space walk was cancelled because of delays in Discovery's launch. Discovery remains in excellent condition, in an orbit with a high point of 380 statute miles and a low point of 369 miles.

Flight controllers said all major activities of the space walk, the second of three on consecutive days of Discovery's space telescope repair and improvement mission, had been accomplished. Controllers reported that power was reaching both of the new pieces of equipment.

"The brains of Hubble have been replaced," said Mission Specialist John Grunsfeld, who worked Thursday in Discovery's cabin with the space-walking crew members outside. About 30 minutes later Hubble began thinking with those new brains. At an evening mission status briefing, John Campbell, Hubble Space Telescope program manager, said the functional checkout of the new computer showed it was functioning well. Checkout of the Fine Guidance Sensor, is continuing.

The length of Thursday's space walk made it the third longest in history, behind only the 8-hour, 15-minute effort on Wednesday by Payload Commander Steve Smith and Grunsfeld and an 8-hour, 29-minute space walk by three Endeavor astronauts on STS-49 on its Intelsat rescue mission in May 1992.

Replacement of one of Hubble's two S-band transmitters is a highlight of Friday's space walk by Smith and Grunsfeld. The transmitter to be replaced had failed. The second transmitter was able to carry the load alone, so no science was lost. The transmitters are considered very reliable, and unlike most of the equipment aboard Hubble, they were not designed to be changed out in orbit. Special tools were developed to enable astronauts to do the job more easily. Installation of a Solid State Recorder to replace a less reliable and less capable 10-year-old recorder is the second major item on the schedule.

Also on the timeline of the space walk, scheduled to begin at 1:50 p.m. CST, is installation of new insulation on equipment bay doors. The spacewalk could, like its two predecessors on STS-103, begin earlier if the crew completes preparations early. Flight controllers are anxious to end this third space walk at 8 p.m. as scheduled.

Discovery remains is in excellent condition, in an orbit with a high point of 380 statute miles and a low point of 364 miles.

The primary goal of today's spacewalk, to be conducted by Mike Foale and European Space Agency astronaut Claude Nicollier, is to install a new computer to replace the one currently in use by Hubble. The new computer is 20 times faster and has six times the memory of the outdated unit being replaced. Nicollier and Foale also will change out one of Hubble's three Fine Guidance Sensors that are used to precisely point the telescope as it conducts scientific observations. The unit being installed today is a refurbished unit that was removed and returned to Earth by the STS-82 crew during its servicing of the telescope in February 1997. If time permits, the space walkers also may perform some optional "get ahead" tasks. Foale has conducted two previous spacewalks, during the STS-63 mission in February 1995 and again in September 1997 as he and Mir Space Station Commander Anatoly Solovyev conducted a six-hour survey of the Mir. This is Nicollier's first spacewalk.

Today's spacewalk is scheduled to begin at 1:50 p.m., but could begin earlier if the crew members complete their preparations ahead of schedule. During the spacewalk, Foale can be recognized by the broken red stripes on the legs of his EVA suit, and Nicollier by the diagonally broken red stripes on his suit.

Discovery's astronauts also supported a functional test of the voltage temperature improvement kits - referred to as VIKs - installed by Steve Smith and John Grunsfeld during their spacewalk yesterday. To ensure the checkout is complete prior to the start of today's scheduled EVA, the astronauts began the work shortly after crew wake-up. During the 90-minute long checkout, investigators will monitor the performance of the voltage kits as the telescope's batteries are charged.

This morning's wake-up music honored the two space-walking astronauts, Nicollier and Foale. Traditional Swiss music was played for Nicollier and the song "Only When I Sleep" by The Corrs was played for Foale.

Discovery remains in excellent condition, in an orbit with a high point of 380 statute miles and a low point of 369 miles.

Astronauts Steve Smith and John Grunsfeld on Friday installed a transmitter that sends scientific data from Hubble to the ground. The transmitter replaced one that failed in 1998. A second transmitter had successfully carried the load without any disruption to Hubble scientific operations. Since the transmitters are considered very reliable, they were not designed to be replaced in orbit and special tools were developed to make the job easier.

Smith and Grunsfeld also installed a solid state digital recorder, replacing an older mechanical reel-to-reel recorder version. The digital Solid State Recorder provides more than 10 times the storage capacity of the old unit. They also applied new insulation on two equipment bay doors.

Both the transmitter and the recorder checked out normally on early tests by telescope controllers.

Two previous space walks on Wednesday and Thursday had completed the highest priority tasks of the mission. Those tasks included installation of six new gyroscopes and six Voltage/Temperature Improvement Kits, giving Hubble a new computer 20 times faster and with six times the memory of the old computer, and replacement of one of Hubble's three Fine Guidance Sensors.

Friday's space walk lasted 8 hours and 8 minutes, ending at 9:25 p.m., making it the fourth longest in history. Part of the reason for the length of the space walk was difficulty in hooking Grunsfeld's suit up to orbiter power after he had returned to Discovery's airlock. Friday's space walk brings the total time of STS-103 extravehicular activity to 24 hours, 33 minutes. This mission's three space walks bring the total amount of time spent servicing Hubble to 93 hours, 13 minutes. Space Shuttle Program space walks now total 317 hours, 3 minutes. And Steve Smith now is the astronaut with the second longest combined space walk time, with 35 hours, 33 minutes behind only Jerry Ross, with 44 hours, 11 minutes.

Discovery is in an orbit with a high point of 380 miles and a low point of 363 miles. All of the orbiter's systems continued to function normally.

Today's planned 7 ½ hour-long space walk will see Smith and Grunsfeld install a transmitter that relays Hubble's scientific data from the telescope to the ground and an upgraded digital recorder replacing an older mechanical version.

The transmitter to be installed today replaces one that failed in 1998. Since that time, the second on-board transmitter has successfully carried the load without any disruption to Hubble operations. The transmitters are considered very reliable, and unlike most of the equipment aboard Hubble, were not designed to be changed out in orbit. Special tools were developed to enable astronauts to do the job more easily.

The digital Solid State Recorder being installed on the telescope will replace an older mechanical model and provide more than 10 times the storage capacity. Smith and Grunsfeld also will apply some new insulation on equipment bay doors to minimize any degradation of the telescope's protective thermal coverings.

The space walk currently is scheduled to being at 1:20 p.m. Central Time and is expected to last about 7 ½ hours.

Mission Control awakened the crew at 8:50 a.m. today to the sounds of Steppenwolf's "Magic Carpet Ride" played for Smith and the children's song "Skinnamarink" by Kimbo for Grunsfeld. Discovery remains in excellent condition, in an orbit with a high point of 380 statute miles and a low point of 364 miles.

"Merry Christmas to all of you down there," replied Brown. "And Hubble will be home for Christmas 'cause today we're going to set her free."

Discovery's astronauts will be doing the gift-giving this afternoon as they return the Hubble Space Telescope to orbit, allowing it to continue its astronomical observations. About 1:45 p.m. CST, European Space Agency astronaut Jean-Francois Clervoy will use Discovery's robot arm to firmly grasp the telescope. After a series of commands to disconnect from external power and confirm Hubble is ready for release, Clervoy will gently lift it out of the support structure in Discovery's payload bay where it has rested since he first plucked it from orbit on December 21. The telescope's aperture door will be commanded open and at 4:50 p.m., Clervoy will release the upgraded telescope.

Hubble's capabilities were enhanced over the course of three spacewalks, lasting a combined total of 24 hours, 33 minutes. Spacewalking astronauts Steve Smith, John Grunsfeld, Mike Foale and Claude Nicollier installed six new gyroscopes, six Voltage/Temperature Improvement Kits, a new more efficient computer, and a refurbished Fine Guidance Sensor. Functional checks and tests of the hardware indicate that the new equipment is working properly and will further enhance the Hubble's scientific capabilities.

This afternoon, the spacewalking team, including arm operator Clervoy, will take a break from their duties to discuss the progress of the mission so far in a series of interviews with CNN, the Associated Press and the Fox News Network. That interview is scheduled for 7:12 p.m. today.

Discovery is in an orbit with a high point of 380 miles and a low point of 363 miles with all systems on board performing well.

European Space Agency Astronaut Jean-Francois Clervoy used the shuttle's robot arm to gently release the telescope at 5:03 p.m. CST, then placed the arm into an upright salute as Commander Curt Brown fired Discovery's steering jets to begin separating from the telescope.

The telescope's re-deployment took place at an altitude of 370 statute miles as the two spacecraft flew over the South Pacific's Coral Sea northeast of Australia, its aperture door opened to the heavens before the release.

By 5:30 p.m. CST, controllers at the Space Telescope Operations Control Center in Maryland were reporting that the telescope was in normal operating mode. Controllers will perform two weeks of testing before resuming observations with the telescope.

"The HST is now orbiting freely once again and is in fantastic shape," Hubble Space Telescope Program Manager John Campbell said after the release. "The spacecraft is being guided by its new gyros, under the control of its brand new computer. The Hubble team is very grateful to the Discovery crew, to the launch and flight teams and to all those who made this mission so successful. We especially thank the families of the entire STS-103 team, who made so many personal sacrifices at this holiday season, enabling the Hubble Space Telescope to resume its voyage of discovery."

At 5:39 p.m. CST, Brown executed a second steering jet burn, lowering Discovery's orbit slightly, so that it would begin orbiting faster than the telescope and move away at just under 6 statute miles per orbit. Afterward, each of the seven astronauts on board called down holiday wishes from space in several languages.

"The familiar Christmas story reminds us that for millennia, people of many faiths and cultures have looked to the skies and studied the stars and planets in their search for a deeper understanding of life and for greater wisdom," radioed Brown. "We, the Discovery crew and this mission to the Hubble Space Telescope, are very proud to be part of this ongoing search beyond ourselves. We hope and trust that the lessons the universe has to teach us will speak to the yearning that we know is in human hearts everywhere -- the yearning for peace on Earth, good will among all the human family. As we stand at the threshold of a new millennium, we send you all our greetings."

Over the course of three space walks, Astronauts Steve Smith, John Grunsfeld, Mike Foale and Claude Nicollier installed six new gyroscopes, six Voltage/Temperature Improvement Kits, a new more efficient computer, and a refurbished Fine Guidance Sensor. Functional checks and tests of the hardware indicate that the new equipment is working well.

The space-walking team, including arm operator Clervoy, also took a break from their duties to discuss the progress of the mission so far in a series of interviews with CNN, the Associated Press and the Fox News Network.

The crew is scheduled to go to bed just before midnight Central time and wake up at 7:50 a.m. Sunday to begin a day of preparations for Monday's landing. Discovery is in a 363 by 380 statute mile orbit with all systems on board performing well.

After waving off the first landing opportunity of the day because of a concern with cross winds at the landing site, the crew was given a "go" to perform the deorbit burn which came at 4:48 p.m. CST and caused Discovery to fall out of its 380 statute mile high orbit to start the journey home to the Kennedy Space Center.

With Commander Curt Brown at the controls, Discovery touched down at 6:01 p.m CST on Runway 33 at the three mile long Shuttle Landing Facility runway at KSC to complete a mission spanning almost 3.3 million miles. Pilot Scott Kelly, Flight Engineer Jean-Francois Clervoy and Mission Specialist Michael Foale joined Brown on the flight deck for entry and landing. Mission Specialists Steve Smith, John Grunsfeld and Claude Nicollier were seated down in the middeck. The end of the STS-103 mission marked the 20th consecutive landing at the Florida spaceport and the 13th night landing in the history of the Shuttle program.

Left behind in orbit, the Hubble Space Telescope now features six new gyroscopes, six new voltage/temperature improvement kits, a new onboard computer, a new solid state recorder and new data transmitter, a new fine guidance sensor along with new insulation on parts of the orbiting telescope.

The STS-103 crew will spend the evening in Florida before returning to Houston on Tuesday. The crew is expected to leave Patrick Air Force Base in Cocoa Beach, FL at approximately 1:30 p.m. CST. The crew should land at Ellington Field at about 5 p.m. where the seven astronauts will be greeted by JSC management and center employees. The crew return ceremony will occur at Hangar 990 and is open to the general public.

• Bay 1-2: Orbiter Docking System - 1800 kg + 3 EMU spacesuits - 360 kg
• Bay 4-13: S0 Truss - 12623 kg. The S0 truss, built by Boeing/Huntington Beach, was 13.4 m long and 4.6 m in diameter. The main truss had a hexagonal cross section. One face carried fluid, power and data cables, while another face carried the rails for the Mobile Transporter. The S0 contained avionics, GPS antennae, and a radiation dose monitor. The S0 would be attached to the LCA (Lab Cradle Assembly) which was attached to the top of the Destiny lab module in 2001. Attached to S0 were:
  • 4 x MTS (Module to Truss Structure) struts. These were used to connect it to the Destiny module
  • Airlock Spur. This was a 4.2 m beam that hinged out to connect to the Quest module and had handrails for spacewalkers
  • Mobile Transporter (MT). This was made by TRW Astro Aerospace in Carpinteria and was an 885 kg, 2.7 m long truck which moved on the S0 rails to transfer heavy cargo along the truss.
• Sill: RMS arm - 410 kg
• Total: 15193 kg

Commander Mike Bloomfield, Pilot Steve Frick, Flight Engineer Ellen Ochoa and spacewalkers Steve Smith, Rex Walheim, Jerry Ross and Lee Morin rocketed away from Launch Pad 39-B at the Kennedy Space Center at 3:44 p.m. Central time as the ISS orbited over the Atlantic Ocean due east of the northeastern United States at an altitude of 240 statute miles.

Launch occurred with only 12 seconds left in the 5-minute launch window due to a brief delay caused by a momentary ground launch system software glitch at the Launch Control Center at the Florida spaceport which paused the countdown at the T-minus 5-minute mark. Once the problem was solved, the countdown resumed.

Atlantis' launch marked a milestone as Ross became the first human to fly in space seven times, breaking a record of six flights previously held by Ross and fellow American astronauts John Young, Story Musgrave, Franklin Chang-Diaz and Curt Brown. No Russian cosmonaut has flown in space more than five times.

Now in their fifth month in orbit, Expedition Four Commander Yury Onufrienko and Flight Engineers Carl Walz and Dan Bursch were able to watch Atlantis' launch through a video uplink from flight controllers in Houston. Atlantis' arrival will mark the first visitors for the Expedition Four crewmembers since their launch back in December.

Less than nine minutes later, Atlantis and its crewmembers settled into orbit as work began to prepare the shuttle for its planned 11-day mission and for a series of rendezvous maneuvers to reach the station on Wednesday morning. Atlantis will actually have to lap the ISS as a result of those maneuvers before its scheduled docking with the outpost Wednesday.

After Atlantis' payload bay doors are opened and approval is given for the start of orbital operations, the seven crewmembers will unstow computers and other gear required for the mission.

If all goes as planned, Atlantis will link up to the station Wednesday just after 11 a.m. Central time, setting the stage for the installation of the S0 (S-Zero) Truss on Thursday morning on the Destiny Laboratory and the first of four spacewalks to mate and activate the new component to Destiny. The S-Zero Truss will serve as a platform upon which other trusses will be attached and additional solar arrays will be mounted in future assembly flights to form a structure longer than the length of a football field. The new truss will also serve as a primary electrical switching station to route power from the stations' arrays to various modules and components.

The shuttle crew will begin its first sleep period at 8:44 p.m. Central time and will be awakened at 4:44 Tuesday morning to begin its first full day in orbit, designed to test the ship's robot arm, spacesuits and rendezvous equipment which will be used over the next few days.

With docking scheduled at 11:06 a.m. Central time (1606 GMT) tomorrow, Commander Mike Bloomfield, Pilot Steve Frick and Mission Specialists Rex Walheim, Ellen Ochoa, Lee Morin, Jerry Ross and Steve Smith verified all of Atlantis' equipment, setting the stage for the orbiter's linkup to a docking port at the forward end of the station's Destiny Laboratory.

Docking is planned over south central China, southwest of Shanghai. The crew will be up early Wednesday to complete preparations and to execute a number of engine firings to draw Atlantis close to the ISS for its eventual docking.

Expedition Four Commander Yury Onufrienko and Flight Engineers Carl Walz and Dan Bursch tidied up their orbital home and completed routine maintenance on the eve of the arrival of their first visitors since they were launched to the ISS back in December. After docking and hatch opening tomorrow, the two crews will run through a dress rehearsal of procedures which will be used on Thursday to maneuver the large S0 (S-Zero) Truss structure from Atlantis' cargo bay for mating to a capture device at the top of Destiny.

Four spacewalks will be conducted by two teams of spacewalkers to electrically and structurally connect the new truss to the ISS. The 13 and a half-ton S-Zero is the mainframe for a series of trusses to follow which will expand the station to a length of a football field.

Late today, Bloomfield and Frick executed a rendezvous maneuver by firing Atlantis' reaction control system jets to refine the shuttle's path to the space station. Several larger engine firings will be conducted Wednesday morning to slow Atlantis' approach to the station, setting up its final path for linkup to the ISS.

With all of its systems functioning in excellent shape, Atlantis orbits the Earth at an altitude of around 220 statute miles. The crew began an eight-hour sleep period at 7:44 Central time this evening and will be awakened at 3:44 Wednesday morning.

The crew will spend today testing and preparing shuttle equipment that will be used to rendezvous and dock with the complex and to install the first and central station truss segment delivered by Atlantis. The crew will power up and test the shuttle's robotic arm, check spacesuits, set up television cameras for the rendezvous activities and prepare the shuttle docking mechanism for contact with the station at 11:06 a.m. Wednesday. Atlantis' mission is to install the 44-foot-long S-Zero (S0) truss on the station, a central girder segment that is one of the most complex pieces of the International Space Station ever launched. The segment is filled with electrical, computer and cooling connections as well as navigation and robotics equipment, including a space railway.

Commander Mike Bloomfield, Pilot Steve Frick, and mission specialists Ellen Ochoa, Steve Smith, Rex Walheim, Jerry Ross and Lee Morin were awakened at 4:44 a.m. to the song "The Best Years of Our Lives" performed by the Baha Men.

Ochoa and Ross, who has now flown in space more times - seven - than any other astronaut, will take a break from the their work onboard Atlantis about 10:44 a.m. CDT for interviews by two Indianapolis, IN, television stations and the Associated Press. Ross is an Indiana native. Late this afternoon, Atlantis' orbital maneuvering system engines will be fired to adjust the rate at which the shuttle is closing in on the station and maintain its course toward a Wednesday morning docking.

Commander Mike Bloomfield guided Atlantis to a linkup with the forward docking port of the station's Destiny Laboratory at 11:05 a.m. Central time as the two vehicles sailed at an altitude of 240 statute miles. The docking culminated a textbook rendezvous executed by Bloomfield and Pilot Steve Frick. As Atlantis docked, Expedition Four Flight Engineer Dan Bursch, a Navy Captain, rang the ISS ship's bell to greet the arriving shuttle crew.

About two hours later, at 1:07 p.m. Central time as the two craft flew over New Zealand, hatches swung open between Atlantis and the station, and the ten crew members greeted one another inside Destiny, marking the arrival of the first visitors for Expedition Four Commander Yury Onufrienko, Flight Engineer Carl Walz and Bursch since they entered the ISS in December for the start of their six-month mission.

After a safety briefing for the shuttle astronauts by Onufrienko, the two crews began to transfer gear for the first spacewalk tomorrow by Steve Smith and Rex Walheim as well as experiments to be housed in Destiny.

Ellen Ochoa joined Bursch to brush up on procedures for the use of the station's Canadarm2 robotic arm tomorrow which will be employed to grapple and unberth the 13 1/2 ton S0 (S-Zero) Truss from Atlantis' cargo bay for mating to a capture device at the top of Destiny. Smith, Walheim, Jerry Ross and Lee Morin will conduct four spacewalks to electrically and structurally mate the S-Zero to Destiny over the next week. Ochoa maneuvered the arm and verified it is in good working order to support the S-Zero operations on Thursday.

Smith and Walheim set up all the equipment in the Quest Airlock on the ISS from which they will mount the first of the four spacewalks to deploy two of the four mounting struts to Destiny and to bring power to the new truss from the U.S. Laboratory. Ochoa is scheduled to grapple the S-Zero around 5 a.m. Central time with the first spacewalk set to get underway around 10 a.m.

Atlantis and the ISS are in excellent shape, orbiting the Earth every ninety minutes in an orbit inclined 51.6 degrees to either side of the Equator.

The two crews began an eight-hour sleep period at 7:44 Central time this evening and will be awakened at 3:44 Thursday morning for the fourth day of the mission.

On Friday, April 12, NASA Administrator Sean O'Keefe will deliver an address on future agency policy entitled, "Pioneering the Future", originating from Syracuse University. The address will be seen on NASA Television beginning at 1 p.m. Central time.

On board the station, the Expedition 4 crew, Commander Yury Onufrienko and flight engineers Carl Walz and Dan Bursch, also awoke at 3:44 a.m. to an alarm-clock-like tone. They have synchronized their sleep schedule to match that of the Atlantis crew to prepare for docked operations.

About two hours after Atlantis docks to the station, the hatches between the two spacecraft will open and Onufrienko, Bursch and Walz will greet their first visitors since beginning their stay aboard the orbiting laboratory last December. After a welcome and safety briefing, all 10 astronauts and cosmonauts will begin transferring equipment and supplies between the two vehicles.

Both crews will jointly review plans for installation of the S-Zero (S0) Truss, including procedures for Thursday's scheduled spacewalk, the first of four during this mission. Ochoa and Bursh will maneuver the station's robotic arm, Canadarm2, through a rehearsal of the motions it will use Thursday to pluck the 44-foot, 27,000 pound truss segment from the shuttle's cargo bay and install it atop the station's U.S. laboratory Destiny.

Major systems aboard Atlantis and the space station continue to function well.

The Atlantis crew - Commander Mike Bloomfield, Pilot Steve Frick and mission specialists Rex Walheim, Ellen Ochoa, Lee Morin, Jerry Ross and Steve Smith - was awakened at 3:44 a.m. by the University of California-Berkeley fight song performed by the school band and "All Right Now," performed by the Stanford University band. Ochoa requested the songs be played for crewmates Walheim and Smith who attended the rival schools.

On board the station, the Expedition 4 crew, Commander Yury Onufrienko and flight engineers Carl Walz and Dan Bursch, also awoke at 3:44 a.m. to an alarm-clock-like tone. Both crews are ready to support the addition of the new segment to the station.

Ochoa, assisted by Bursch, will command the space station robotic arm, Canadarm2, to grapple S0 about 5 a.m. Canadarm2 will lift the truss segment out and away from Atlantis' cargo bay and temporarily install it on the U.S. laboratory Destiny. The Lab Cradle Assembly will provide a semi-rigid structural hold until the truss segment is permanently attached during four spacewalks this week.

The first spacewalk is set to begin about 10 a.m. today as Smith, wearing the suit with solid red stripes, and Walheim, in a solid white suit, float out of the station's Quest airlock. After initial setup procedures, their tasks during the 6½ hour venture include attaching two of four S0 mounting struts to Destiny, as well as an avionics tray that contains power, data and fluid cables and an umbilical system connected to the Mobile Transporter. If time permits, Smith will remove a launch support beam and also go inside the truss to install two circuit breakers.

Ochoa and Bursch will move Walheim on Canadarm2 to worksites throughout the spacewalk. Bloomfield and Frick will use the shuttle's robotic arm cameras to take video of the spacewalkers while Ross guides them through the outlined procedures.

During the S-Zero installation, Atlantis Commander Mike Bloomfield and Pilot Steve Frick operated the shuttle's robotic arm to provide additional camera views to Ochoa and Bursch, who were working in the Destiny Lab at one of the robotic workstations. The truss will serve as the backbone for future station expansion to the length of a football field. S-Zero contains navigational devices, computers, cooling and power systems necessary to attach additional laboratories to the complex.

Within minutes after the new truss was temporarily latched to the Destiny Lab, mission specialists Rex Walheim and Steve Smith left the station's Quest Airlock at 9:36 a.m. Central time to begin the first of four spacewalks of the mission to electrically and structurally mate S-Zero to the station.

Smith and Walheim first unfurled and firmly attached two of four mounting struts on the truss to Destiny before deploying trays of avionics equipment and cables on the truss which include power, data and fluid lines connecting Destiny to the S-Zero. They also attached an umbilical system from the truss to the Mobile Transporter housed on the forward face of the huge girder. The umbilical will enable the Transporter, which is the first railcar in space, to move up and down the length of the station to position the ISS robotic arm for future assembly work. Two other struts on the truss will be mated to Destiny Saturday during the second spacewalk, permanently bolting the truss to the Laboratory.

Working deliberately to connect all of the critical power connections, Walheim spent the day working at the end of the station's Canadarm2, the first time the large arm has been used as a form of cherry picker to maneuver astronauts during assembly work at the ISS. Smith operated as a so-called "free-floater", tethered to the station and to various work sites around the truss itself. Atlantis astronaut Jerry Ross and ISS Flight Engineer Carl Walz took turns choreographing the spacewalk from the aft flight deck of the shuttle.

With all but two tasks successfully completed, Smith and Walheim returned to Quest late this afternoon and ended their spacewalk at 5:24 p.m. Central time, completing a 7 hour, 48 minute excursion. It was the 35th spacewalk devoted to station assembly and the 10th staged from the station itself. As Smith and Walheim wrapped up their work, flight controllers reported that the activation of the S-Zero Truss had begun and that all of the initial systems appear to be in excellent shape.

Time ran out before Smith and Walheim could install two circuit breakers on the truss, but that task will be picked up on a subsequent spacewalk.

After a long and tedious day, the shuttle and station crew members were scheduled to begin an eight-hour sleep period at 7:44 p.m. Central time and will be awakened just before 4 a.m. Friday.

Atlantis Commander Mike Bloomfield, Pilot Steve Frick, and Mission Specialists Ellen Ochoa, Rex Walheim, Lee Morin, Jerry Ross and Steve Smith - and the Expedition Four crew - Commander Yury Onufrienko and Flight Engineers Carl Walz and Dan Bursch - spent their day transferring equipment and science experiments between the shuttle and the station. They also transferred oxygen from the shuttle to one of four high-pressure gas tanks on the Quest Airlock. The tanks are used to repressurize the airlock at the end of each spacewalk staged from the module.

Station flight controllers reported that four new computers on the S-Zero truss were tested successfully, as were new devices to determine the station's orientation relative to the Earth, Global Positioning System navigational antennas and the Thermal Control System for the 13 ½ ton girder, which will be the backbone for other trusses and solar array towers to be mounted on the station in the next year.

The two crews transferred a number of experiments from Atlantis to the station's Destiny Laboratory and reviewed plans for the second and third spacewalks of the mission Saturday and Sunday to continue the outfitting of the new truss.

Saturday's spacewalk by Ross and Morin is scheduled to begin around 9:30 a.m. Central time. The two spacewalkers will complete the bolting of two aft struts on the truss to Destiny, forming a secure structural mate between S-Zero and the Laboratory. Ross and Morin will also attach a second umbilical system to the truss' Mobile Transporter, a form of rail car that will eventually move the station's robotic arm some 350 feet up and down the entire length of the completed truss.

The two crews enjoyed some off duty time this afternoon and are scheduled to begin their sleep period at 7:44 p.m. Both crews will be awakened Saturday at 3:44 a.m.

The Atlantis crew - Commander Mike Bloomfield, Pilot Steve Frick, and mission specialists Ellen Ochoa, Rex Walheim, Lee Morin, Jerry Ross and Steve Smith - was awakened at 3:44 a.m. Central time by the song "Testify to Love," by Wynonna Judd played for Bloomfield from his family. On board the station, the Expedition 4 crew, Commander Yury Onufrienko and flight engineers Carl Walz and Dan Bursch, awoke about 30 minutes later.

Morin and Ross will move an experimental plant growth chamber to a rack inside the station's Destiny lab. This experiment will replace a protein crystal growth experiment that will return to Earth on board Atlantis. Walheim and Ochoa will install a freezer in the lab for future crystal samples.

Oxygen and nitrogen will be transferred from Atlantis to the station to refill the airlock high-pressure tanks with the gasses breathed by spacewalkers. The crew will also prepare for and review the procedures for the next two spacewalks, on Saturday and Sunday, to continue hookup of the S0 Truss.

Systems on the S0 Truss are functioning well after its installation Thursday. Friday, ground controllers will activate the Global Positioning System and the Rate Gyro Assembly located on S0 that will begin providing navigation and attitude data for the station.

Crewmembers will take a break to talk with reporters from MSNBC, CBS Radio Network and WWJ-TV in Detroit at 11:28 a.m. At 1 p.m. NASA television will switch to live coverage of NASA Administrator Sean O'Keefe's address on "Pioneering the Future." The address will be replayed on NASA TV at 3 p.m.

After two hours of time off during the afternoon, both crews are scheduled to begin their sleep period at 7:44 p.m.

Dubbed the "Silver Team" by their colleagues because of their age, 54-year old Jerry Ross and 49-year old Lee Morin of Atlantis' crew had little trouble extending and bolting the final two struts of the new S-Zero (S0) truss to the Destiny Laboratory, insuring that the centerpiece for the future expansion of the station would be permanently secured to accept additional trusses and solar array towers over the next year. The station will ultimately span some 350 feet from end to end, the length of a football field.

The first two struts of the truss were mated to Destiny on Thursday by the other Atlantis spacewalking team, Steve Smith and Rex Walheim, who will venture back outside Sunday to continue the outfitting of the truss and to reroute electrical power to the station's 58-foot long robotic arm.

Morin worked at the end of the ISS' Canadarm 2 throughout the day during his first spacewalk, while Ross, America's most experienced spacewalker and the most flown space traveler in history, remained tethered to the station to provide "free-floating" support during the eighth spacewalk of his career.

Smith, Walheim and Expedition Four Flight Engineer Dan Bursch helped choreograph the spacewalk from Atlantis' aft flight deck, while shuttle crew member Ellen Ochoa and station Flight Engineer Carl Walz took turns maneuvering Morin as they operated Canadarm2 from a robotic work station inside Destiny.

Shuttle and station Commanders Mike Bloomfield and Yury Onufrienko and shuttle Pilot Steve Frick provided photographic and television support for the spacewalk, the 36th devoted to ISS assembly over the past 3 ½ years.

After the truss struts were bolted in space, Ross and Morin removed a series of panels and clamps that provided structural support for the truss during its launch in Atlantis' cargo bay.

The spacewalkers then began work to install a backup device containing an umbilical reel for the Mobile Transporter railcar on the truss that will provide redundancy to a similar device mounted on the truss Thursday. The two sets of umbilicals for the Mobile Transporter, which is designed to move the robotic arm up and down the length of the completed station truss, provide power, data and video capability for the system, which will be tested for the first time in orbit Monday.

Ross tried to remove a restraining bolt on the mechanism which, if required, can cut the umbilical cable should it snag during its operation, but the bolt proved to be a bit balky and did not back out of its socket as planned. Flight controllers decided not to spend additional time troubleshooting the stubborn bolt today after engineers determined that the cable cutter cannot inadvertently fire in its current configuration. The backup umbilical system is operating normally and the stubborn bolt will be dealt with on one of the mission's two remaining spacewalks. The primary umbilical system installed Thursday is also operating normally.

The spacewalk, which was conducted out of the station's Quest Airlock, began at 9:09 a.m. Central time and concluded at 4:39 p.m. as Ross and Morin repressurized the outer compartment of the two-chamber module.

Late today, Frick fired Atlantis' steering jets in a one-hour procedure to slowly reboost the space station by about 2 statute miles. It was the first of three scheduled reboost maneuvers to eventually raise the orbit of the ISS by about 6 statute miles before Atlantis departs the station on Wednesday.

The ten shuttle and station crew members are scheduled to begin their eight-hour sleep period at 7:44 p.m. and will awaken Sunday just before 4 a.m. to begin preparations for the third spacewalk of the flight.

The Atlantis crew - Commander Mike Bloomfield, Pilot Steve Frick, and mission specialists Ellen Ochoa, Rex Walheim, Steve Smith, Morin and Ross - was awakened at 3:44 a.m. by the song "Voodoo Chile," by Jimi Hendrix. It was played for Morin, who will be making his first spacewalk, at the request of his wife. On board the station, the Expedition 4 crew, Commander Yury Onufrienko and flight engineers Carl Walz and Dan Bursch, also were awakened at 3:44 a.m.

During their 6½-hour spacewalk Ross, wearing a spacesuit with broken red stripes, and Morin, wearing a spacesuit with diagonal broken stripes, will complete the structural attachment of S0's remaining two struts to the station's Destiny laboratory. With all four of the struts attached to Destiny, S0 will be able to support its design loads, including the solar arrays that will be on the ends of the truss at assembly complete.

After attaching the struts, Ross and Morin will remove the large metal rods used to support S0 during launch and store them on the truss. The pair will also attach a second cable system to the Mobile Transporter, which will eventually enable the space station's robotic arm, Canadarm2, to ride a railway along the truss structure.

For today's spacewalk Morin will be working from a platform at the end of the Canadarm2, operated by Ochoa. Using the shuttle robotic arm cameras, Bloomfield and Frick will take photographs and video of the spacewalkers. Walheim will coordinate the spacewalk from inside.

Both crews are scheduled to begin their eight-hour sleep period at 7:44 p.m.

The stage is now set for the inaugural run Monday of the so-called Mobile Transporter, a flatcar designed to transport the space station's robotic arm up and down an integrated truss system that will span the length of a football field.

Within minutes after starting their spacewalk at 8:48 a.m. Central time, Steve Smith and Rex Walheim released a claw-like device on the top of the Destiny Laboratory to which the new 13 ½ ton S-Zero (S0) truss was initially attached on Thursday. With the truss' four large struts now securely bolted to Destiny, the claw was no longer needed.

Smith and Walheim then reconfigured a number of connectors providing electricity to the 58-foot-long Canadarm2 robotic arm on the station so it can be powered from the S-Zero truss rather than Destiny. The arm has two sets, or "strings" of avionics equipment for its operation. As Smith and Walheim worked deliberately, one set of avionics was rewired and tested, followed by a separate set of redundant avionics.

Smith spent most of the day riding at the end of the shuttle's robotic arm, which was operated by Pilot Steve Frick during the rewiring of its companion station arm. Walheim was the so-called "free-floating" astronaut, tethered to the station to assist Smith. It was the seventh spacewalk of Smith's career. He is the second most experienced U.S. spacewalker behind crewmate Jerry Ross, who helped choreograph today's excursion from inside Atlantis with the help of Lee Morin. It was Walheim's second spacewalk.

With Canadarm2 successfully rewired and both of its electrical, data and video circuit sets checked out, Smith and Walheim pressed ahead to release clamps which secured the Mobile Transporter to the S-Zero truss during its launch last week. The railcar, which weighs about 1900 pounds, will be commanded Monday by ground controllers to move about 32 feet up and down the truss at a glacial speed of a little less than one inch per second in the first test of its computers, drive motors, suspension unit, video and data umbilicals and the first section of rails on the S-Zero.

The railcar, and an associated Mobile Base System device to be installed on the transporter in early June on the next shuttle assembly flight to the ISS, will ultimately enable the robotic arm to travel to various worksites on the expanding trusses of the station for future construction. The Mobile Base System will be the platform upon which the Canadarm2 will attach itself to be driven up and down the length of the ISS.

The only task not completed today was the attachment of a 14-foot ladder called the Airlock Spur from the S-Zero truss to the Quest Airlock designed to simplify the path for future spacewalkers moving back and forth from the truss to the airlock itself.

As the spacewalk neared its completion, final diagnostic tests of the newly wired station arm were taking longer than planned, and because the Canadarm2 is required for the airlock ladder to be pivoted away from the truss to Quest, flight controllers decided to defer its installation until the final spacewalk on Tuesday.

Smith and Walheim finally returned to Quest and completed their spacewalk at 3:15 p.m. Central time with the repressurization of the airlock.

Atlantis astronaut Ellen Ochoa and ISS Expedition Four crew member Dan Bursch backed up Frick in the operation of the shuttle's robot arm during today's spacewalk, the 37th devoted to space station assembly. Commander Mike Bloomfield documented the spacewalk from Atlantis' aft flight deck while Expedition Four Commander Yury Onufrienko and Flight Engineer Carl Walz continued to transfer supplies from the shuttle to the station for future use.

Late today, Frick conducted an hour-long reboost of the ISS, using Atlantis' steering jets to move the station higher by about two statute miles. It was the second of three planned maneuvers to raise the station's altitude and the second in as many days.

The ten crew members are scheduled to begin an eight-hour sleep period at 7:44 p.m. Central time tonight and will be awakened just before 4 a.m. to prepare for the testing of the new Mobile Transporter.

They are scheduled to step out of the station's Quest airlock at 9:34 a.m. Their first task is to release a claw atop the lab that temporarily secured the truss to it during the initial installation. Walheim, wearing a solid white spacesuit, will release the latch as Smith, wearing a spacesuit with red stripes, begins making connections to route power, data, and video through the truss for later operation of the space station robotic arm, Canadarm2. During the 6½-hour spacewalk, Smith will be working from a platform on the station arm, operated by Mission Specialist Ellen Ochoa and Flight Engineer Dan Bursch.

Walheim will install circuit breakers in the truss, a task left over from the first spacewalk, which lasted 7½ hours. Together they will then turn their attention to the Mobile Transporter, spending about 45 minutes releasing its many launch restraints and removing a small thermal cover from a radiator on the railcar. Then they return to work on the electrical connections for about another hour and a half.

After transferring tools and testing sensors on the side of S0, the last task will be to install the Airlock Spur. The 14-foot beam, fitted with handrails, will stretch from Quest to the forward side of S0, helping future spacewalkers work more efficiently.

Inside the shuttle/station complex, Mission Specialists Lee Morin and Jerry Ross will coach the spacewalkers through the outlined tasks. Shuttle Commander Mike Bloomfield and Pilot Steve Frick will provide photographic and video support during the spacewalk, using Atlantis' robotic arm.

Atlantis' crew was awakened about 3:52 a.m. by the song "All Star," performed by Smash Mouth from the Shrek movie soundtrack. The song was played for Walheim by his family.

Onboard the space station, Expedition Four Commander Yury Onufrienko, Flight Engineer Carl Walz and Bursch were awakened at 3:44 a.m. Both crews are scheduled to begin their sleep period at 7:44 p.m.

Expedition Four Flight Engineer Carl Walz sent commands from a laptop computer to the Mobile Transporter to move off of its launch position on the forward face of the new S-Zero (S0) truss, and at 7:22 a.m., the flatcar began its slow trek to an initial worksite 17 feet down a rail which spans the entire 44 feet of the girder.

It took only a half hour to traverse the distance, but sensitive software in the transporter prevented an automatic latching of the railcar to the worksite. Ground controllers accomplished the latching through a methodical series of commands.

Engineers believe that the subtle effects of weightlessness are causing the railcar to "lift" off its tracks by a microscopic distance, thus interfering with magnetic sensors that tell the transporter its position relative to each worksite. The effect is that the sensors are losing contact with magnetic positioning strips on the truss rail, preventing an automatic latching of the transporter. Manual commanding of the latching is working however, and the system is said to be in excellent working order.

The Mobile Transporter software controls about 20 motors, directing it to travel from one point to another, latch itself down to the truss, and plug itself into a power source. The transporter must latch with about three tons of force to insure a stable platform for the eventual mounting of the Canadarm2 robotic arm. On the next shuttle assembly flight to the ISS in June, a platform called the Mobile Base System will be mounted to the transporter upon which Canadarm 2 will eventually be attached so it can travel the length of a football field to support future assembly of station components.

Late today, the transporter traveled to a second worksite where manual latching commands were again required, then inched back to the first worksite, where the railcar was parked at 5:40 p.m. Central time and manually latched in place for a final time to await the arrival of the Mobile Base System component on the STS-111 mission. In all, the transporter traveled 72 feet from worksite to worksite at a glacial pace of about one inch per second.

Engineers believe a minor software modification may restore the transporter's ability to automatically latch itself to any worksite. All other transporter systems functioned perfectly throughout its initial test.

Atlantis Commander Mike Bloomfield, Pilot Steve Frick, Mission Specialists Ellen Ochoa, Rex Walheim, Lee Morin, Jerry Ross and Steve Smith, and Expedition Four Commander Yury Onufrienko and Flight Engineers Walz and Dan Bursch spent the day monitoring the transporter tests and continued the transfer of equipment and supplies from Atlantis to the station.

In addition, about 100 pounds of oxygen and 30 pounds of nitrogen have been transferred from Atlantis to the tanks on the Quest Airlock to support future spacewalk activity.

The fourth and final spacewalk of the flight will be conducted on Tuesday by Ross and Morin beginning around 9:30 a.m. Central time. At the start of the planned 6 ½ hour excursion, Ross and Morin will pivot a 14-foot ladder away from the S-Zero truss for attachment to Quest to act as a pathway for future spacewalkers. They will also install external lights on the Unity module, test microswitches on the sides of the S-Zero truss which will be used to confirm the attachment of future truss segments, troubleshoot a balky bolt on a cable cutting system on the Mobile Transporter and tie down a portion of insulation on one of four navigational antennas on the S-Zero.

The ten Shuttle and Station crew members are scheduled to begin an eight-hour sleep period at 7:44 p.m. Central time and will be awakened shortly before 4 a.m. Tuesday to prepare for the final spacewalk of the mission.

Ground controllers in mission control will command the Mobile Transporter to move up and down the truss three times, testing its computers, drive motors, suspension unit, video and data umbilicals, and the railway itself. The railcar will travel a total of about 71 feet at speeds of 1, 0.4 and 0.1 of an inch per second, stopping at future worksites to test its ability to latch and unlatch itself to the railway.

This is the first time that a software-controlled movable robot has been used on an orbiting vehicle. The Mobile Transporter software controls about 20 motors, directing it to travel from one point to another, latch itself down to the truss, and plug itself into a power source. The Mobile Transporter ultimately will move the station's robotic arm, Canadarm2, along the orbiting laboratory's 356-foot Integrated Truss.

The Atlantis crew - Commander Mike Bloomfield, Pilot Steve Frick, Mission Specialists Ellen Ochoa, Rex Walheim, Lee Morin, Jerry Ross and Steve Smith - was awakened at 3:48 a.m. to "Magic Carpet Ride" by Steppenwolf, dedicated to Smith. The station crew - Commander Yury Onufrienko, Flight Engineers Carl Walz and Dan Bursch - was awakened at 4:14 a.m.

The crews will continue to transfer equipment between the two spacecraft and will review procedures for the fourth and final spacewalk of the mission, scheduled for Tuesday.

The 10 crewmembers will participate in a news conference with media representatives at NASA centers in Florida and Houston and at Mission Control- Moscow. The event will be carried live on NASA television beginning at 11:47 a.m. CDT. Afterwards, the crews will have a few hours off. Both crews are scheduled to begin their eight-hour sleep period at 7:44 p.m.

Ross and Morin began the fourth and final spacewalk of the STS-110 mission and the 38th devoted to space station construction at 9:29 a.m. Central time, first pivoting a 14-foot beam called the Airlock Spur from the S-Zero truss to the Quest Airlock to provide a quick pathway for future spacewalkers working on truss assembly.

Ross then conducted tests of switches on both sides of the 44-foot long truss to insure they will work properly later this year in confirming the attachment of additional truss segments to the S-Zero. The main truss of the ISS will eventually stretch more than 350 feet, longer than a football field.

The two spacewalking grandfathers pressed ahead to install floodlights on the station's Unity connecting module and the Destiny Laboratory which will provide illumination for future spacewalkers as they move around the expanding outpost.

Ross and Morin then affixed a work platform on the station for future construction work, installed electrical converters and circuit breakers, dressed up a piece of insulation around one of the four navigational antennas on the truss and attached shock absorbers to the new Mobile Transporter railcar. The shock absorbers will prevent vibrations to the station's robotic arm from the future use of carts on the truss which will be used to move spacewalkers from one end of the station to another.

The only tasks not accomplished were the removal of a balky bolt from a backup cable cutting device on one of two umbilical systems for the Mobile Transporter, which was successfully tested on Monday and the installation of a gas analyzer on the truss which proved to be faulty.

The bolt will have no impact on the operation of the flatcar, upon which a Mobile Base System platform will be mounted in June as the ultimate base for the transport of the station's robotic arm up and down the length of the ISS. The gas analyzer was considered the lowest priority of the flight.

With all of their major work completed, Ross and Morin returned to the Quest Airlock and concluded the spacewalk at 4:06 p.m. Central time.

Atlantis Mission Specialist Ellen Ochoa and Expedition Four Flight Engineer Dan Bursch operated the station's Canadarm2 robotic arm to move Ross around the ISS during the spacewalk while Morin operated as the "free-floating" spacewalker, tethered to the station to assist Ross in the final tasks of the mission. For Ross, America's most experienced spacewalker, it was his ninth excursion to conduct work in the void of space during his career, totaling 58 hours and 18 minutes of spacewalking time. Only Russian cosmonaut Anatoly Solovyev has performed more spacewalks in human spaceflight history. Today's spacewalk was the second for Morin. Rex Walheim and Expedition Four crew members Carl Walz helped choreograph the spacewalk from Atlantis' aft flight deck.

While the spacewalkers went about their work, Shuttle and Station Commanders Mike Bloomfield and Yury Onufrienko, Pilot Steve Frick, and Steve Smith continued their transfer of equipment to and from both Atlantis and the ISS and provided photographic and television support to Ross and Morin.

With all of the objectives having been successfully accomplished for the mating and outfitting of the S-Zero truss to the ISS, the stage is set for Wednesday's final farewells between the two crews and undocking of Atlantis from the station at 1:31 p.m. Central time as the two craft sail some 244 statute miles above the north Atlantic due west of Ireland. Atlantis is scheduled to land at the Kennedy Space Center early Friday afternoon.

The shuttle crewmembers will begin an eight-hour sleep period tonight at 7:14 p.m. Central time followed thirty minutes later by the station crew. Atlantis' crew will be awakened at 3:14 a.m. Wednesday to prepare for undocking. The station crew will be awakened an hour later.

Work during the 6½-hour spacewalk includes installation a 14-foot beam extending from Quest to the newly installed S-Zero (S0) Truss to help spacewalkers maneuver around the station more efficiently. They will install halogen work lights on the Unity module and the U.S. laboratory, Destiny -- the 40-watt lamps are five times more powerful than standard 40-watt lamps and will shine a 9- by 7-foot elliptical beam of light 20 feet away. The spacewalkers will setup and partially assemble a work platform.

Ross, working from the station's robotic arm, also will install shock absorbers to either side of the Mobile Transporter to provide a barrier and attach point between the railcar and future hand-propelled carts that will be used by spacewalkers.

Morin will deploy an instrument to measure and characterize the radiation environment outside the station. He also will troubleshoot a balky bolt on a redundant cable cutting system on the Mobile Transporter. A successful test run of that railcar concluded late Monday when ground controllers commanded it to latch onto the railway and plug into a power source. The railcar is ready to receive the Mobile Base System during the next shuttle mission, STS-111, giving the station's Canadarm2 points of attachment on the rail-car base capable of moving along the station's Integrated Truss.

Additional tasks include installing handrails on S0, relocating tools for STS-111 spacewalks, adjusting a thermal blanket partly obstructing a GPS antenna on S0, performing photo and video documentation of station components and checking out a gauge that is designed to detect minute amounts of gas in the environment of space.

The Atlantis crew - Commander Mike Bloomfield, Pilot Steve Frick, Mission Specialists Ellen Ochoa, Rex Walheim, Steve Smith, Morin, and Ross- was awakened at 3:44 a.m. to "I Am an American," performed by the Purdue University Marching band. It was dedicated to Purdue graduate Ross. The station crew - Commander Yury Onufrienko, Flight Engineers Carl Walz and Dan Bursch - was also awakened at 3:44 a.m.

After more than a week of joint operations between the shuttle and station crews, Pilot Steve Frick backed Atlantis away to a distance of about 400 feet in front of the outpost, where he began a 1 1/4 lap flyaround of the ISS, newly equipped with the 27,000 pound S-Zero truss, the first segment of a truss structure which will ultimately expand the station to the length of a football field. Aboard the station, Flight Engineer Dan Bursch rang a ship's bell in the Unity module to mark Atlantis' departure in what has become a tradition.

Finally, at 3:15 p.m., as Atlantis flew directly above the station, Frick fired the shuttle's jets one more time in a separation maneuver to depart the station for good.

Left behind on the ISS are Expedition Four Commander Yury Onufrienko and Flight Engineers Carl Walz and Bursch, now in their 133rd day in space and their 131st day on board the outpost.

Also left behind on the station were more than a ton of supplies, almost 200 pounds of oxygen and nitrogen for the station's Quest Airlock, 1,463 pounds of water and the new truss, which will serve as a backbone for future station construction and a power switching station for new solar arrays to be delivered to the ISS next year. Atlantis's week-long visit to the ISS was the 13th shuttle mission devoted to station assembly and resupply.

Earlier today, Commander Mike Bloomfield, Frick and Mission Specialists Rex Walheim, Ellen Ochoa, Steve Smith, Lee Morin and Jerry Ross completed final transfers of logistical supplies to the station and bid farewell to their station counterparts in the Destiny Laboratory. Hatches between the station and the shuttle swung shut at 11:04 a.m. Central time and leak checks were performed to insure that all was in order for the undocking.

As Atlantis' crew turns its attention to preparations for landing at the Kennedy Space Center Friday afternoon, the Expedition Four crew will prepare to button up the ISS temporarily and enter its Soyuz return craft early Saturday for a brief flyover from one docking port to another.

With Onufrienko at the controls, the Soyuz will undock from the station's Zarya nadir docking port at around 4 a.m. Central time Saturday, back out to a distance of about 250 feet and redock to the Pirs Docking Compartment 35 minutes later. That will clear the Zarya docking port for the arrival of a new Soyuz return vehicle and a three-man taxi crew on April 27 for a week-long visit.

Both Atlantis and the International Space Station are in excellent shape following their joint mission. Atlantis' astronauts are scheduled to begin an eight-hour sleep period at 6:44 p.m. Central time and will be awakened just before 3 a.m. Thursday for what is expected to be their final full day in orbit.

Farewells and closing of the hatches between the spacecraft is set to begin about 10:30 a.m. About 1:30 p.m., Atlantis astronaut Jerry Ross will send commands to release the docking mechanism. The initial separation will be provided by springs that will gently push the shuttle away from the station. When Atlantis is about two feet away from the station and the docking devices are clear of one another, Pilot Steve Frick will fire Atlantis' steering jets to begin slowly moving away.

About 45 minutes after undocking, when Atlantis is 450 feet away, Frick will fly the shuttle around the station 1¼ times. The flyaround is set to begin at 2:16 p.m. and will last about an hour. Atlantis will move directly over the station, then behind it, underneath it, and back in front, where the flyaround began. The last quarter-circle brings the shuttle directly above the station. Finally, Frick will fire Atlantis' jets to move away from the station about 3:15 p.m. Atlantis is scheduled to land at the Kennedy Space Center at 11:26 a.m. CDT Friday.

Atlantis leaves behind the newly installed S-Zero (S0) Truss, the first part of the main truss that will support cooling and power systems essential for the addition of future international laboratories to the station. All of the S0 systems have been operating well since its attachment to the station's U.S. laboratory Destiny on Thursday.

The shuttle also delivered additional supplies and science experiments for the station crew to work with during its final weeks on the station. The Expedition Four crew - Commander Yury Onufrienko and Flight Engineers Carl Walz and Dan Bursch - is scheduled to return to Earth aboard the space shuttle Endeavour in June.

The Atlantis crew - Commander Mike Bloomfield, Frick, Mission Specialists Ellen Ochoa, Rex Walheim, Steve Smith, Lee Morin, and Ross- was awakened at 3:44 a.m. to "Noah," performed by Frick when he was a teen-ager. The station crew was awakened at 4:14 a.m.

Commander Mike Bloomfield, Pilot Steve Frick and Flight Engineer Ellen Ochoa activated one of three hydraulic power units on Atlantis and tested all of the shuttle's aerosurfaces to ensure that Atlantis will have full controllability during its high-speed return to Earth Friday. Bloomfield and Frick then test-fired Atlantis' steering jets, which were declared ready to support entry and landing.

Bloomfield, Frick and Ochoa joined crewmates Rex Walheim, Lee Morin, Jerry Ross and Steve Smith to stow all of the equipment they have used over the past 10 days and parked the shuttle's KU-band dish antenna in preparation for the closing of Atlantis' cargo bay doors early Friday morning.

Atlantis has two landing opportunities at the Kennedy Space Center on Friday. The first begins with the firing of Atlantis' braking rockets at 10:20 a.m. Central time, enabling the shuttle to drop out of orbit for its hour-long descent back to Earth and a touchdown on the 3-mile long Shuttle Landing Facility at KSC at 11:26 a.m. Central time. In the unlikely event weather prevents a landing on the first opportunity, a second opportunity is available for a Florida landing, beginning with the deorbit burn of the orbital maneuvering system engines on Atlantis at 11:59 a.m. Central time, resulting in a landing at KSC at 1:03 p.m. Central time.

The weather forecast calls for very favorable conditions for landing at the Florida spaceport Friday, with only scattered clouds and light winds expected. As a result, the backup landing site at California's Edwards Air Force Base was not called up for support Friday. Atlantis has enough consumables to stay in orbit, if necessary, until Monday.

Meanwhile, on board the ISS, Expedition Four Commander Yury Onufrienko and Flight Engineers Carl Walz and Dan Bursch spent a relatively quiet day in the wake of a week of joint operations with Atlantis' crew to install and activate the S-Zero (S0) truss and the Mobile Transporter railcar on the complex. Both of the new components continue to be checked out and are said to be in excellent shape.

Onufrienko, Walz and Bursch will spend part of the day Friday deactivating some of the ISS systems as they prepare to board their Soyuz return vehicle early Saturday for a brief flyover from its current docking location at the nadir port of the Zarya module to the Pirs Docking compartment. The relocation of the Soyuz, which is expected to take about 35 minutes, will begin with undocking Saturday at 4:02 a.m. Central time (902 GMT). Coverage of the operation on NASA Television begins at 3 a.m. Central time (800 GMT).

The movement of the Soyuz 3 vehicle from Zarya to Pirs opens the Zarya port for the arrival of a new Soyuz 4 craft on April 27 by a three-man "taxi" crew comprised of Commander Yuri Gidzenko, formerly of the Expedition One crew, Flight Engineer Roberto Vittori of the European Space Agency and South African spaceflight participant Mark Shuttleworth. They will be launched from the Baikonur Cosmodrome in Kazakhstan on April 25 and will spend about a week in joint operations with the Expedition Four crew before departing from Pirs in the Soyuz 3 craft on the night of May 4.

The crew of Atlantis was scheduled to begin a scheduled eight-hour sleep period at 6:14 p.m. today, and will be awakened just after 2 a.m. Friday to prepare for entry and landing. All shuttle and ISS systems are operating normally.

If Atlantis lands on Friday, the STS-110 astronauts will return home to Ellington Field in Houston near the Johnson Space Center at around 1 p.m. Central time Saturday.

The crew - Commander Mike Bloomfield, Pilot Steve Frick, Mission Specialists Ellen Ochoa, Rex Walheim, Lee Morin, Jerry Ross and Steve Smith - was awakened at 2:44 a.m. to "Somewhere Over the Rainbow," performed by Bloomfield's daughter.

Bloomfield, Frick and Ochoa will test fire the reaction control system jets and flight control surfaces that will be used to guide Atlantis through the atmosphere on Friday morning. Atlantis is scheduled to return to the Kennedy Space Center in Florida at 11:26 a.m. CDT Friday where preliminary weather forecasts for landing are favorable.

Crewmembers will take a break from their on orbit work today to talk with media representatives from CNN, WDIV-TV in Detroit and the Fox News Network this morning in an interview beginning at 9:14

Atlantis' orbital maneuvering jets will be fired twice today. Once will be for scientists to look at the exhaust's effects on radar echoes and effects of orbital kinetic energy on the ionosphere. The other firing will reduce the cross range for Friday's backup landing opportunity in Florida. Walheim, Morin, Ross and Smith will continue to pack away equipment and supplies onboard the shuttle and prepare the cabin for landing.

On board the International Space Station the Expedition 4 crew - Commander Yury Onufrienko and Flight Engineers Dan Bursch and Carl Walz - was awakened at 3 a.m. They are preparing for their next visitors, a Soyuz taxi crew slated to arrive April 27. Onufrienko, Walz and Bursch, will board the current Soyuz spacecraft and move it from its location on the Zarya docking port to the Pirs docking compartment on Saturday to make room for the replacement Soyuz.

The crew of Atlantis will begin a scheduled eight-hour sleep period at 6:14 p.m. today, waking just after 2 a.m. Friday to prepare for reentry and landing of Atlantis concluding a successful mission to the station.

Commander Mike Bloomfield eased Atlantis to a textbook landing on runway 3-3 at the Florida spaceport at 11:27 a.m. Central time under clear skies and light winds. Bloomfield, Pilot Steve Frick and Mission Specialists Rex Walheim, Ellen Ochoa, Lee Morin, Jerry Ross and Steve Smith completed an 11-day flight in which four spacewalks were conducted to deliver and activate the new S-Zero (S0) girder to the ISS, which will serve as the centerpiece for a truss that will eventually span the length of a football field. Solar arrays will be mounted on the truss as well as new station modules. The S-Zero component will also serve as a switching station for electricity from the station's solar arrays to ISS elements. In addition, the truss is a base for the first rail system in space through the use of its Mobile Transporter and the upcoming Mobile Base System to be delivered to the ISS in June on which the station's robotic arm will be affixed to move up and down the length of the outpost.

The shuttle crewmembers were scheduled to depart Atlantis about an hour after landing to be driven back to the crew quarters at KSC for medical tests and reunions with their families.

The STS-110 astronauts will return home to Hangar 990 at Ellington Field in Houston near the Johnson Space Center at around 1 p.m. Central time Saturday for a welcome home ceremony. The public is invited to attend.

Meanwhile, aboard the ISS, Expedition Four Commander Yury Onufrienko and Flight Engineers Carl Walz and Dan Bursch spent the day configuring station systems for the temporary closure of the complex early Saturday in advance of a short departure in their Soyuz return vehicle and a relocation of the craft to another docking port.

Onufrienko, Walz and Bursch will board their Soyuz return vehicle early Saturday for a brief flyover from its current docking location at the nadir port of the Zarya module to the Pirs Docking compartment. The relocation of the Soyuz, which is expected to take about 35 minutes, will begin with undocking Saturday at 4:02 a.m. Central time (902 GMT). Coverage of the operation on NASA Television begins at 3 a.m. Central time (800 GMT).

The movement of the Soyuz 3 vehicle from Zarya to Pirs opens the Zarya port for the arrival of a new Soyuz 4 craft on April 27 by a three-man "taxi" crew comprised of Commander Yuri Gidzenko, who served on the first resident crew of the ISS, Flight Engineer Roberto Vittori of the European Space Agency and South African spaceflight participant Mark Shuttleworth. They will be launched from the Baikonur Cosmodrome in Kazakhstan on April 25 and will spend about a week in joint operations with the Expedition Four crew before departing from Pirs in the Soyuz 3 craft on the night of May 4.

Major systems aboard the ISS continue to function well as the station orbits at an average altitude of about 247 statute miles.

Atlantis has two landing opportunities at KSC today. The first begins with the firing of Atlantis' braking rockets at 10:20 a.m. and a landing at 11:26 a.m. CDT. A second opportunity for a Florida landing would see the deorbit burn at 11:59 a.m. and a landing at KSC at 1:03 p.m. CDT. Forecasts call for favorable weather for landing in Florida Friday, with only scattered clouds expected. The backup-landing site at California's Edwards Air Force Base was not called up today. Atlantis has enough consumables to stay in orbit until Monday.

The crew of Atlantis - Commander Mike Bloomfield, Pilot Steve Frick, and Mission Specialists Ellen Ochoa, Rex Walheim, Lee Morin, Jerry Ross and Steve Smith - was awakened at 2:21 a.m. by the song "Message in a Bottle," performed by The Police.

Meanwhile, aboard the ISS, Expedition 4 Commander Yury Onufrienko and Flight Engineers Carl Walz and Dan Bursch monitored station systems this morning during another reboost of the orbiting laboratory. The Progress cargo ship's jets were fired to raise the station's altitude a little more than half a mile. During the STS-110 mission, Atlantis did three station reboosts, totaling about six miles.

The station crew also will deactivate some ISS systems today to prepare to board the Soyuz return vehicle early Saturday for its 35-minute move from the nadir port of the Zarya module to the Pirs Docking compartment. The relocation of the Soyuz will begin with undocking Saturday at 4:02 a.m. Coverage on NASA Television begins at 3 a.m.

The move frees the Zarya port for the arrival of a new Soyuz 4 craft on April 27 with a three-man "taxi" crew comprised of Commander Yuri Gidzenko, Flight Engineer Roberto Vittori of the European Space Agency and South African spaceflight participant Mark Shuttleworth. They will be launched from the Baikonur Cosmodrome in Kazakhstan on April 25 and will spend about a week aboard the station before departing in the Soyuz 3 craft May 4.