BY SPACEFLIGHT NOW

Follow the space shuttle Atlantis' mission to deliver the S0 truss to the International Space Station. Reload this page for the very latest. A text only version is also available for faster access.

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TUESDAY, APRIL 23, 2002

The Soyuz rocket that will launch a fresh lifeboat to the International Space Station and tourist Mark Shuttleworth was rolled to the pad today at the Baikonur Cosmodrome. Liftoff remains scheduled for 0626 GMT (2:26 a.m. EDT) on Thursday.

SATURDAY, APRIL 20, 2002
0946 GMT (5:46 a.m. EDT)

The Soyuz relocation has gone well today, Mission Control reports. The Expedition Four crew -- on the 136th day of their voyage in space -- will head back inside the space station later this morning and begin reactivating the various systems. The station was placed in care-taker status in the unlikely event the Soyuz couldn't redock, forcing the crew to return to Earth.

We'll post a couple movie clips of today's activities shortly.

The next Soyuz with the "taxi crew" of Russian commander Yuri Gidzenko, Italian astronaut Roberto Vittori and South African space tourist Mark Shuttleworth is scheduled for launch from Baikonur Cosmodrome on Thursday at 2:26 a.m. EDT (0626 GMT). The craft will dock to the just-vacated nadir-port of Zarya next Saturday around 4 a.m. EDT.

The taxi crew will spend a week aboard the station before undocking in the older Soyuz around 7:05 p.m. on May 4 and returning to Earth.

The Soyuz spacecraft have a six-month service life in space and have to be replaced as such.

0941 GMT (5:41 a.m. EDT)

The docking probe on the front of the Soyuz is now retracting to form a tight seal with the station.

0937 GMT (5:37 a.m. EDT)

Contact and capture! The Soyuz spacecraft carrying the Expedition Four crew of commander Yuri Onufrienko and American flight engineers Dan Bursch and Carl Walz docked to the Pirs module, returning to the International Space Station after a brief 21-minute trip. Docking occurred 247 miles above Central Asia.

The relocation of the Soyuz lifeboat from Zarya module to Pirs was done to prepare for the arrival of a fresh Soyuz capsule next Saturday. The new vehicle will dock to the now-open Zarya port, which is the preferred parking spot for the station's emergency escape craft.

0935 GMT (5:35 a.m. EDT)

Onufrienko working to line up with the docking port.

0932 GMT (5:32 a.m. EDT)

The approach to docking is now underway.

0931 GMT (5:31 a.m. EDT)

Onufrienko reports the Soyuz is now aligned with Pirs.

0929 GMT (5:29 a.m. EDT)

Soyuz has performing a roll maneuver and is now heading for Pirs, which is located one module over. Pirs is attached to the Earth-facing side of the Zvezda service module.

0924 GMT (5:24 a.m. EDT)

The Soyuz is now stationkeeping at a distance of about 160 meters away from the station. The capsule will maneuver laterally to align with the Pirs module.

0916 GMT (5:16 a.m. EDT)

Undocking! The Soyuz TM-33 spacecraft with the Expedition Four crew aboard has undocked from the Earth-facing port of the Russian Zarya module for today's move to the Pirs docking module. The International Space Station is now uninhabited, albeit for only a matter of minutes until the Soyuz flies one module over and redocks. Commander Yuri Onufrienko is piloting the Soyuz in this relocation maneuver.

The undocking occurred at 5:16 a.m. EDT above Africa about 247 miles up.

0800 GMT (4:00 a.m. EDT)

The three Expedition Four crew members are aboard their Soyuz lifeboat attached to the International Space Station in preparation to move the capsule to another docking port. The Russian-made craft will undock from the Zarya module at about 5:15 a.m EDT, backing away by at least 100 meters and then moving over a short distance to align with the Pirs docking compartment. The Soyuz will then approach and dock to Pirs. The entire operation should take no more than 40 minutes.

All three station residents -- commander Yuri Onufrienko and American flight engineers Dan Bursch and Carl Walz -- are going on the ride today in case the Soyuz can't redock the outpost and has to return to Earth today. No one wants to be left in space without an emergency lifeboat spacecraft. Key systems of the station have been powered down, too, while the astronauts are away.

The Russians swap out Soyuz capsules at the station every 6 months. This relocation is being performed so a fresh Soyuz, which is due to arrive at the station a week from today, can dock at Zarya. The "taxi crew" flying up the replacement Soyuz -- Russian commander Yuri Gidzenko, Italian astronaut Roberto Vittori and South African space tourist Mark Shuttleworth -- will live on the station for seven days before piloting the old Soyuz back to Earth.

FRIDAY, APRIL 19, 2002

Commander Michael Bloomfield, making his first landing at the controls of a space shuttle, guided Atlantis to a smooth touchdown on Runway 33 at the Kennedy Space Center today to close out a near-flawless space station assembly mission. Landing occurred at 12:27 p.m. EDT (1627 GMT). Read our full story.

Video coverage for subscribers only:
   VIDEO: LANDING AS SEEN LIVE WITH FULL AUDIO QT or RV
   VIDEO: VIEW OF LANDING FROM VAB ROOF QT or RV
   VIDEO: SIDE VIEW OF ATLANTIS' TOUCHDOWN QT or RV
   VIDEO: REPLAY FROM CAMERA AT RUNWAY MID-POINT QT or RV
   VIDEO: TOUCHDOWN FROM SOUTH END OF RUNWAY QT or RV
   VIDEO: VIEW FROM NORTH END OF THE RUNWAY QT or RV
   VIDEO: CREW POST-LANDING COMMENTS QT or RV
   VIDEO: SHUTTLE PROGRAM UPDATE WITH LINDA HAM QT or RV
   MORE: COMPLETE SFN+ VIDEO INDEX

1735 GMT (1:35 p.m. EDT)

With all seven astronauts now off the shuttle, the motorized Crew Transport Vehicle is backing away from Atlantis. It is expected that at least some of the shuttle astronauts will make the traditional walkaround of the Atlantis on the runway shortly.

Later, all seven astronauts will be driven to Kennedy Space Center's Operations & Checkout Building to be reunited with their families and have dinner. The crew is scheduled to fly back to their homes in Houston tomorrow.

Atlantis will be towed off the runway to its hangar later this afternoon. The shuttle's next flight is the STS-112 mission in August that will launch the starboard truss segment S1 to continue building the station's backbone.

1658 GMT (12:58 p.m. EDT)

The Crew Transport Vehicle -- a modified airport "People Mover" -- has pulled up to the Atlantis' crew hatch for the astronauts to enter. The CTV features beds and comfortable seats for the astronauts to receive medical checks after returning to Earth's gravity from the weightless environment of space.

1645 GMT (12:45 p.m. EDT)

The main engine nozzles have been gimbaled to the "rain drain" position. And Atlantis' three Auxiliary Power Units will now be shut down.

1641 GMT (12:41 p.m. EDT)

The astronauts are going through standard post-landing safing of Atlantis following a smooth touchdown today. The body flap is being set and the external tank umbilical doors on the shuttle's belly have been opened. The side hatch and drag chute pyrotechnics have been safed, and the landing gear is reported safed. On the runway, workers have arrived with instruments to "sniff" the shuttle's exterior to check for any hazardous vapors.

1633 GMT (12:33 p.m. EDT)

Post-landing safing of Atlantis is underway by the astronauts following a smooth touchdown today.

Here are the preliminary landing times in Eastern Daylight Time and Mission Elapsed Time:

Main Gear Touchdown
12:26:57 p.m. EDT
MET: 10 days, 19 hours, 42 minutes, 38 seconds

Nose Gear Touchdown
12:27:09 p.m. EDT
MET: 10 days, 19 hours, 42 minutes, 50 seconds

Wheels Stop
12:28:07 p.m. EDT
MET: 10 days, 19 hours, 43 minutes, 48 seconds

1628 GMT (12:28 p.m. EDT)

WHEELS STOP. Atlantis is back home at its point of origination at the Kennedy Space Center after a successful mission that delivered the keystone truss structure to expand the capabilities of the International Space Station.

1627 GMT (12:27 p.m. EDT)

TOUCHDOWN! Main gear touchdown. Drag chute deployed. Nose gear touchdown. Space shuttle Atlantis rolls out on Runway 33 after traveling 4 1/2 million miles in 171 orbits of Earth over the past 11 days.

1626 GMT (12:26 p.m. EDT)

Landing gear down and locked. Standing by for touchdown on Kennedy Space Center's Runway 33.

1625 GMT (12:25 p.m. EDT)

Field in sight. Commander Bloomfield can see the runway as he pilots Atlantis to landing at Kennedy Space Center. The shuttle descending at a rate seven times steeper than that of a commercial airliner.

1624 GMT (12:24 p.m. EDT)

Atlantis is in the Heading Alignment Cylinder, an imaginary circle to align with Runway 33. The crew is piloting the shuttle through a 290-degree right-overhead turn. Altitude under 40,000 feet.

1623 GMT (12:23 p.m. EDT)

Commander Mike Bloomfield has taken manual control of Atlantis. The sonic booms have been heard in KSC area, announcing the shuttle's arrival.

1622 GMT (12:22 p.m. EDT)

Now five minutes from landing at the Kennedy Space Center. Mission Control has given the crew a "go" for normal drag chute deployment after main gear touchdowm. Range to touchdown 67 miles. Speed 950 mph.

1620 GMT (12:20 p.m. EDT)

Seven minutes to touchdown. Range to the runway 70 miles. Speed currently 1,800 mph. Altitude 85,000.

1619 GMT (12:19 p.m. EDT)

Air data probes have been deployed from the shuttle's nose to feed air speed, altitude and angle of attack information to the computers for navigation.

1618 GMT (12:18 p.m. EDT)

Atlantis has made landfall over southwestern Gulf shore of Florida.

1617 GMT (12:17 p.m. EDT)

Touchdown is now 10 minutes away. The shuttle, just a glider during its return to Earth, is right on the planned ground track.

Altitude 27 miles, speed 4,700 mph, 250 miles from the runway.

1616 GMT (12:16 p.m. EDT)

Atlantis remains on the proper track for landing in 11 minutes at Kennedy Space Center. Distance less than 400 miles.

The Merritt Island tracking station at the Cape, called MILA, has locked on to signal from space shuttle Atlantis. This provides more detailed navigation data for tracking the spaceplane as it streaks to touchdown at Kennedy Space Center. And the TACAN navigation units aboard Atlantis are now receiving data from beacons located at the ground.

1614 GMT (12:14 p.m. EDT)

Atlantis is now crossing the Gulf of Mexico. The shuttle is about to begin banking back to the left. Altitude 33 miles, speed 8,100 mph.

1612 GMT (12:12 p.m. EDT)

Now 15 minutes until landing. Speed currently 10,500 mph. Range to the runway about 850 miles.

Touchdown will occur on Runway 33 at the Kennedy Space Center -- the southeast to northwest strip of the Shuttle Landing Facility. Upon arrival at the heading alignment circle in skies over KSC, commander Mike Bloomfield will make a 290-degree right-overhead turn to align Atlantis with the runway. Touchdown is expected at 12:27 p.m. EDT at 195 knots some 2,600 feet down the runway.

The Shuttle Landing Facility was built in 1975. It is 300 feet wide and 15,000 feet long with 1,000-foot overruns at each end. The strip is located about three miles northwest of the 525-foot tall Vehicle Assembly Building.

1610 GMT (12:10 p.m. EDT)

Now 17 minutes from landing. Atlantis has made landfall over southern Mexico. The current altitude is 40 miles.

1608 GMT (12:08 p.m. EDT)

Atlantis is now reversing its bank to the right to further reduce speed.

1607 GMT (12:07 p.m. EDT)

Now 20 minutes from landing. Atlantis is 1,800 miles to the runway with an altitude of 228,000 feet and speed of 14,400 mph.

1602 GMT (12:02 p.m. EDT)

Atlantis is 3,020 miles to touchdown, speed 16,400 mph, altitude 250,000 feet.

The roll control jets on the shuttle are being turned off and the aerosurfaces on the spacecraft now able to be used as the vehicle continues descent into the atmosphere. All the wing flaps will be active shortly with the exception of the rudder, which won't be useful until the shuttle slows to Mach 5.

1600 GMT (12:00 p.m. EDT)

Altitude 49 miles. Atlantis is about to begin the first of four banks to scrub off speed as it plunges into the atmosphere. These turns basically remove the energy Atlantis built up during launch. This first bank will be to the left at 82 degrees.

1558 GMT (11:58 a.m. EDT)

Mission Control has just decided to switch ends of the runway for Atlantis' landing today. Instead of using the northwest end of the Shuttle Landing Facility, Atlantis will head to Runway 33 -- the southeast to northwest approach. This will mean the commander Bloomfield will make a 290 degree right-overhead turn to align with Runway 33.

The change was made to ensure sun glare isn't a problem for Bloomfield and given acceptable winds for both approaches.

1555 GMT (11:55 a.m. EDT)

ENTRY INTERFACE. The protective tiles on the belly of Atlantis are now feeling heat beginning to build as the orbiter enters the top fringes of the atmosphere -- a period known as Entry Interface.

The shuttle is flying with its nose elevated 40 degrees, wings level, at an altitude of 400,000 feet, passing over the southern Pacific Ocean, about 4,400 nautical miles from the landing site, at a velocity of Mach 25, descending at a rate of over 500 feet per second.

Touchdown is set for 12:27 p.m. EDT at Kennedy Space Center in Florida.

1553 GMT (11:53 a.m. EDT)

Altitude 88 miles. Now about two minutes away from Entry Interface.

Atlantis' onboard computers have switched to the OPS-304 program, which governs entry phase of the mission.

1549 GMT (11:49 a.m. EDT)

Altitude 123 miles as Atlantis nears the final orbital sunrise of this mission. Now 38 minutes from touchdown.

All three auxiliary power units are running to supply pressure to the shuttle's hydraulic systems, which in turn move Atlantis's aerosurfaces and deploy the landing gear. One unit was started prior to the deorbit burn; the others just a few moments ago. The units are only activated during the launch and landing phases of the shuttle mission.

1541 GMT (11:41 a.m. EDT)

Altitude 183 miles. Excess propellant has been dumped from two jets on the forward reaction control system of the shuttle.

1536 GMT (11:36 a.m. EDT)

Atlantis is now at an altitude of 219 miles.

The shuttle's track home will take the craft above the Pacific Ocean on northeastward track towards Kennedy Space Center. The shuttle will make landfall above southern Mexico, then skirt along the northern shore of the Yucatan Peninsula before crossing the Gulf of Mexico. Atlantis will arrive in the skies of Florida on the southwest coast and continue across the central portion of the state, flying just south of Orlando. Once in the vicinity of KSC, Commander Bloomfield will perform a wide, sweeping 245-degree left-overhead turn to align with Runway 15 -- the northwest to southeast three-mile strip.

1530 GMT (11:30 a.m. EDT)

Atlantis is now passing over the southwestern tip of Australia at an altitude of about 245 miles.

1525 GMT (11:25 a.m. EDT)

Onboard guidance is maneuvering Atlantis from its heads-down, tail-forward position needed for the deorbit burn to the reentry configuration of heads-up and nose-forward. The nose also will be pitched upward 40 degrees. In this new position, the black tiles on the shuttle's belly will shield the spacecraft during the fiery plunge through the Earth's atmosphere with temperatures reaching 3,000 degrees F. Atlantis will begin interacting with the upper fringes of the atmosphere above the South Pacific in about a half-hour.

1521 GMT (11:21 a.m. EDT)

DEORBIT BURN COMPLETE. Atlantis has successfully completed the deorbit burn, committing the shuttle for its journey back to Earth. Landing is scheduled for 12:27 p.m. EDT at Kennedy Space Center in Florida.

Today's landing will be the 59th to occur at Kennedy Space Center in the history of space shuttle program. Dating back to May 1996, this will mark the 37th of the last 41 shuttle missions to land in Florida. KSC is the most used landing site for the shuttle. Edwards Air Force Base in California has seen 48 landings and White Sands in New Mexico supported one.

1519 GMT (11:19 a.m. EDT)

DEORBIT BURN IGNITION. Flying upside down and backwards above the east-central Indian Ocean, northwest of Australia, Atlantis has begun the deorbit burn. The firing of the two orbital maneuvering system engines on the tail of the shuttle will last two minutes and 19 seconds, slowing the craft to slip from orbit. The retro-burn will send Atlantis towards a touchdown at 12:27 p.m. EDT on a runway just a few miles from the Kennedy Space Center launch pad where the shuttle lifted off 11 days ago.

1514 GMT (11:14 a.m. EDT)

Pilot Steve Frick has activated one of three Auxiliary Power Units in advance of the deorbit burn, now five minutes away. The other two APUs will be started later in the descent to provide pressure needed to power shuttle's hydraulic systems that move the wing flaps, rudder/speed brake, drop the landing gear and steer the nose wheel. NASA ensures that at least one APU is working before committing to the deorbit burn since the shuttle only needs a single unit to make a safe landing.

1507 GMT (11:07 a.m. EDT)

Atlantis has maneuvered to the deorbit burn attitude. The shuttle is flying upside-down and backwards with its tail pointed in the direction of travel. The shuttle's vent doors have been closed and final configuring of the onboard computers has been completed.

1456 GMT (10:56 a.m. EDT)

GO FOR THE DEORBIT BURN! With very favorable landing weather today at Kennedy Space Center, entry flight director Leroy Cain in Mission Control has given space shuttle Atlantis' astronauts the "go" to perform the deorbit burn at 11:18:59 a.m. EDT for return to Earth.

The upcoming two-minute, 19-second retrograde burn using the twin orbital maneuvering system engines on the tail of Atlantis will slow the shuttle's velocity just enough to slip the craft out of orbit and begin the plunge back into the atmosphere.

Atlantis is headed to a landing at 12:27 p.m. EDT on Runway 15 at KSC. The landing will conclude the 10-day, 19-hour, 43-minute STS-110 mission.

1448 GMT (10:48 a.m. EDT)

Entry flight director Leroy Cain is polling his team in Mission Control and receiving a final update on weather before making the decision on the deorbit burn.

Meanwhile, pilot Steve Frick has completed the auxiliary power unit prestart, which positions switches in the cockpit in the ready-to-start configuration.

1419 GMT (10:19 a.m. EDT)

Now one hour away from the deorbit burn. The firing of Atlantis' twin orbital maneuvering system engines on the tail of the shuttle will begin at 11:18:59 a.m. EDT and last for two minutes and 19 seconds, slowing the ship by just over 250 feet per second. The braking will drop the shuttle from orbit, putting Atlantis on course to fall back into the atmosphere for the hour-long glide to the Kennedy Space Center landing site. Touchdown is expected at 12:27 p.m. EDT on Runway 15. However, the runway selection could change to Runway 33 to lessen the sun glare for commander Bloomfield today.

1338 GMT (9:38 a.m. EDT)

The weather conditions at Kennedy Space Center remain favorable for Atlantis' return home today at 12:27 p.m. EDT.

The crew is scheduled to spend a few minutes right now going over the game plan for entry. The commander and pilot will then begin suiting up in the day-glow orange launch and entry suits before strapping into their seats. The rest of the crew are slated to begin suiting up in a little more than a half an hour.

The "go/no go" decision for the deorbit burn by entry flight director Leroy Cain is expected at about 11 a.m. EDT.

1253 GMT (8:53 a.m. EDT)

Atlantis' clam-shell-like payload bay doors have been closed and locked in preparation for today's fiery descent into Earth's atmosphere and landing at Kennedy Space Center.

There are no problems to report this morning. The weather forecast for Florida is favorable and expected to remain acceptable today.

Also, Mission Control has given commander Mike Bloomfield a "go" to transition Atlantis' onboard computers from the OPS-2 software used during the shuttle's stay in space to OPS-3, which is the software package that governs entry and landing.

And Atlantis will soon maneuver to a new orientation in space to improve the communications link with NASA's orbiting data relay satellites.

Meanwhile, the Flight Dynamics Officer in Mission Control has revised the start time for the deorbit burn that will slow the shuttle and drop it from orbit. The two-minute firing of the twin orbital maneuvering system will now begin at 11:19 a.m. EDT. The landing time has been tweaked to 12:27 p.m. EDT.

FRIDAY, APRIL 19, 2002

After a trouble-free space station assembly mission, space shuttle Atlantis and her crew of seven astronauts are headed home today to wrap up an 11-day voyage. Touchdown at Kennedy Space Center's shuttle runway is scheduled for 12:26 p.m. EDT (1626 GMT).

The weather is expected to favorable with a "Bermuda high" dominating the Cape area. Forecasters are calling for scattered clouds at 4,000 and 20,000 feet, easterly winds 6 to 10 knots and a temperature of 81 degrees.

The astronauts will begin their deorbit preparation timeline at 7:20 a.m. EDT. Atlantis' payload bay doors will be closed at 8:40 a.m. as the crew readies the ship for the fiery plunge back into Earth's atmosphere.

If the weather cooperates and there are no technical issues, Entry Flight Director Leroy Cain will give his "go" for the deorbit burn around 11 a.m.

The two-minute, 14-second engine firing by Atlantis starting at 11:20:27 a.m. will slow the ship by about 253 feet per second, just enough to slip from orbit to begin the trek home.

Atlantis will hit the top of the atmosphere at period called Entry Interface at 11:55:01 a.m. at an altitude of 400,000 feet and 4,300 miles from the runway over the Pacific Ocean.

Landing on KSC's Runway 15 is expected at 12:26:21 p.m. EDT.

If the weather prevents an on-time homecoming, Atlantis will remain in space and target a second and final landing opportunity of the day in Florida. That would begin with a two-minute, 16-second deorbit burn at 12:58:50 p.m. to slow the shuttle by 257 feet per second. Touchdown would follow at 2:02:39 p.m.

Given the good forecast, NASA has opted not to call up the backup landing site at Edwards Air Force Base in California on Friday. The shuttle has enough onboard consumables to remain aloft through Monday.

Watch this page for live updates of Atlantis' entry and landing throughout day.

THURSDAY, APRIL 18, 2002

Entry flight director Leroy Cain says the shuttle Atlantis is in good shape for landing Friday and with forecasters predicting ideal weather, the astronauts appear to be on track for an on-time Kennedy Space Center touchdown at 12:26:21 p.m. EDT (1626:21 GMT). Read full story.

WEDNESDAY, APRIL 17, 2002

With pilot Stephen Frick at the controls, the shuttle Atlantis undocked from the international space station today at 2:31 p.m. as the two spacecraft raced across the North Atlantic Ocean at five miles per second. Read full story.

Read our earlier status center coverage.