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FRIDAY, FEBRUARY 27, 2004

The cooling system in cosmonaut Alexander Kaleri's spacesuit malfunctioned during a planned five-and-a-half-hour spacewalk Thursday evening, forcing flight director Vladimir Solovyev to order an early end to the excursion. Read our full story.

0212 GMT (9:12 p.m. EST Thurs.)

The crew has found a kink in the cooling system tubing of Kaleri's spacesuit that could explain the problem experienced during the spacewalk, officials report. Once the kink was straightened, the water flow appeared to return to normal.

The Foale and Kaleri are examining the suit and backpack to determine why the sublimator device appeared to break down during the EVA. The sublimator maintains cooling and regulates humidity within the suit.

0145 GMT (8:45 p.m. EST Thurs.)

Russian flight controllers are instructing Mike Foale to remove his spacesuit first so he can perform an inspection of Kaleri's suit in an effort to troubleshoot the cooling system problem.

0131 GMT (8:31 p.m. EST Thurs.)

The airlock is being repressurized after the premature end of today's spacewalk. Russian officials cut short the EVA due to a cooling system failure of cosmonaut Alexander Kaleri spacesuit.

Activities that were not performed include relocation of laser light retro reflector devices from the aft end of Zvezda service module and the changing of sample packages in a Russian experiment to examine the residue from station thruster firings. The retro reflectors are being studied as navigation devices for the European Space Agency's Automated Transfer Vehicle, which will begin delivering cargo to the station in the spring or summer of 2005.

0121 GMT (8:21 p.m. EST Thurs.)

With the completion of today's spacewalk, the EVA time over 52 excursions outside the International Space Station now stands at 322 hours and 32 minutes since 1999. Of the 27 spacewalks to originate from the station itself (excluding shuttle-based EVAs), the elapsed time is 155 hours and 17 minutes.

0112 GMT (8:12 p.m. EST Thurs.)

The hatch is closed, officially ending today's spacewalk at 8:12 p.m. EST. The spacewalk lasted three hours and 55 minutes, about two hours shorter than planned.

0109 GMT (8:09 p.m. EST Thurs.)

Commander Mike Foale and Alexander Kaleri are back inside the Pirs docking module's airlock. They have been given approval by Russian flight controllers to close the hatch.

0100 GMT (8:00 p.m. EST Thurs.)

Here is how the problem was reported between the crew and Mission Control.

"I have rain inside the helmet," Kaleri told Russian flight controllers a little while ago. "I have water inside the visor."

"How much water? Could you estimate?" a controller replied.

"Well, quite some amount, a significant amount. It felt like rain," Kaleri said through a translator.

"It seems the sublimator has failed, according to our telemetry your sublimator has failed," the ground reported.

"You think so?"

"Tell me, can you feel which side the sun is shining, can you feel it on one side of your body?"

"Very insiginficantly. If I didn't know where it was, I couldn't very well guess," Kaleri replied.

"Well then it's not too bad."

"It's not like I'm baking on the beach."

0050 GMT (7:50 p.m. EST Thurs.)

Just past the three-and-a-half hour mark of today's spacewalk. The crew will be climbing back into the airlock and repressurizing, ending this EVA short of its intended duration. Several tasks will remain unaccomplished by this early termination of the spacewalk due to a spacesuit problem.

0042 GMT (7:42 p.m. EST Thurs.)

EVA TO END EARLY. The spacewalkers have been told to wrap up their current work with the Russian Replaceable Cassette Container experiments and return to the Pirs airlock due to a problem with cooling system on Kaleri's spacesuit.

0039 GMT (7:39 p.m. EST Thurs.)

"Everything had been proceeding by the book and on schedule until about 40 minutes ago when Alexander Kaleri reported that a couple of drops of water had formed on the inside of his visor and that his suit temperature was increasing slightly as well, not to a particularly uncomfortable level but to the point where additional humidity was beginning to form within the suit and within his visor," NASA spokesman Rob Navias reports.

"Russian flight controllers are indicating an apparent failure of a sublimator cooling device, which maintains cooling and regulates humidity within the suit itself."

0028 GMT (7:28 p.m. EST Thurs.)

There is a problem with the cooling system in Russian cosmonaut Alexander Kaleri's Orlan spacesuit. Officials are discussing whether to continue with the spacewalk or have the crew return to the airlock early.

Kaleri has been instructed to cycle the pumps in hopes of clearing the trouble.

The spacewalkers are currently working with another Russian witness plate experiment while waiting for a decision by officials.

0023 GMT (7:23 p.m. EST Thurs.)

Flight controllers are examining data from Alexander Kaleri's spacesuit. He is reporting floating water inside the suit and the temperature is warmer than desired.

THURSDAY, FEBRUARY 26, 2004
2357 GMT (6:57 p.m. EST)

The one MPAC-SEED package that is remaining outside the station has been reopened. The suitcase-like panels of the experiment were closed so the package could be relocated earlier in the spacewalk. With it now firmly attached to the new position and work completed in the surrounding area, the panels are open again.

The other MPAC-SEED experiment removed from the station hull today will be brought inside for later return to Earth.

2347 GMT (6:47 p.m. EST)

The European-sponsored Matroshka experiment has been mounted to Zvezda and umbilical lines hooked up. Inside the experiment container is a "phantom head and torso" resembling a human.

For the next year, the experiment will provide real-time radiation dosage measurements to a computer inside the service module. The information will be used to determine the amount of radiation that spacewalking astronauts experience.

"The levels of radiation inside the station are well documented though the levels experienced by astronauts outside of the ISS are still unclear. In order to determine precise measurements, Matroshka simulates the human body within a spacesuit as closely as possible," the European Space Agency says.

"The Matroshka experiment facility consists of several different layers, hence the reason for naming it after the famous Russian matrioshka dolls. The simulated human element of the experiment is called the Phantom. It is composed of natural bone and a material, which closely resembles natural tissue. A lower-density material is used to simulate the lungs. These 'tissue' layers are covered with a simulated skin layer. The Phantom is itself housed in an external container, which represents a spacesuit.

"Radiation sensors are placed in and around the Phantom at different key organ locations such as the stomach, lungs, colon, eyes and skin and also within the spacesuit element. Knowing the radiation doses suffered by sensitive body organs is crucial for assessing the hazards from cosmic radiation."

2317 GMT (6:17 p.m. EST)

Now two hours into today's spacewalk. The spacesuits are functioning properly, Mission Control says, based upon data received during the most recent Russian ground station pass.

The second MPAC-SEED package has been moved.

The crew is now preparing to install the Matroshka radiation monitoring experiment on Zvezda.

2305 GMT (6:05 p.m. EST)

The panels on both MPAC-SEED experiment packages have been closed by the spacewalkers. They have since removed one package from the holding bracket on Zvezda and temporarily stowed on a handrail. Now, the spacewalkers are moving the second package from its location to the bracket just freed up.

2247 GMT (5:47 p.m. EST)

After enjoying a brief rest period while the International Space Station was flying through orbital darkness, the spacewalkers are resuming activities to remove one of the Japanese Micro-Particles Capture and Space Environment Exposure Device (MPAC-SEED) material experiments and moving another to a different bracket on the Zvezda module's hull to continue its exposure. These are suitcase-sized panels that have been outside for a couple of years.

MPAC is designed to capture tiny bits of space debris and micro-meteoroids for scientists to study the size, composition and impact energy of such objects in the space station's orbit.

SEED is exposing different materials to space to help future spacecraft builders in understanding the environment's effects.

2217 GMT (5:17 p.m. EST)

Russian flight controllers have temporarily disabled jet thrusters on the Zvezda service module to protect the spacewalkers as they work on the space station's exterior. The spacewalkers have made their way from the Pirs module to Zvezda where several experiments will be either removed, relocated or new ones installed.

2155 GMT (4:55 p.m. EST)

Astronaut Michael Foale and Alexander Kaleri began a planned five-and-a-half hour spacewalk today, leaving the international space station vacant in the first such outing since crew sizes were reduced in the wake of the Columbia shuttle disaster. Read our full story.

We will continue to post periodic updates on the spacewalk's progress on this page throughout the evening.

2147 GMT (4:47 p.m. EST)

Now 30 minutes into today's spacewalk by the International Space Station's Expedition 8 residents. Foale and Kaleri got down to business in swift order, exchanging a Replaceable Cassette Container experiment package on the Pirs module that has exposed candidate materials to the space environment for analysis.

A bundle of other experiments has been brought out of the airlock for transport to the Zvezda service module. The various packages, including the Matryoshka torso radiation experiment, will be installed by the spacewalkers over the course of the next few hours.

Space station systems are functioning normally, Mission Control says, as the complex operates without anyone side during this spacewalk.

2118 GMT (4:18 p.m. EST)

Expedition 8 commander Mike Foale has opened the hatchway on the Pirs docking module leading to the vacuum of space, officially marking the start of the spacewalk at 4:17 p.m. EST. This excursion by Foale and Russian cosmonaut Alexander Kaleri is expected to last more than five-and-a-half hours as the two men exchange experiment packages and move equipment outside the International Space Station.

2105 GMT (4:05 p.m. EST)

The crew has been given approval to switch their Orlan spacesuits to internal battery power.

2053 GMT (3:53 p.m. EST)

Mission Control reports that the airlock depressurization continues smoothly. Checks of the spacesuits have been peformed without trouble. All of the spacewalk preparations have progressed well today.

2008 GMT (3:08 p.m. EST)

The International Space Station will be unoccupied for several hours today as the two residents step outside for a spacewalk to work on external experiments and equipment. The EVA by Expedition 8 commander Michael Foale and flight engineer Alexander Kaleri begins at 4:14 p.m. EST (2114 GMT) and is scheduled to last five-and-a-half hours.

The crewmen have donned their the Russian Orlan spacesuits and commenced depressurization of the Pirs docking module's airlock for the spacewalk. The spacewalk officially begins at hatch opening.

The to-do list for this spacewalk, the 52nd in the life of the space station and 27th to originate from the orbiting lab, is quite extensive with many chores outside the Russian segment of the complex.

The spacewalkers will remove one suitcase-sized package and relocate another -- both part of the Japanese MPAC-SEED experiment. This experiment is studying micro-meteor impacts and material exposure in the space environment. This experiment was deployed by Expedition 3 in October 15, 2001.

One new experiment that will be attached to the outer hull of the Zvezda service module is a Russian experiment named Matryoshka, which will provide data on radiation exposure to the human body during spaceflight.

Laser light retro reflector devices from the aft end of Zvezda will be removed. The reflectors are being studied as navigation devices for the European Space Agency's Automated Transfer Vehicle, which will begin delivering cargo to the station in the spring of 2005.

They also will change sample packages in a Russian apparatus that is used to study the residue created from station thruster firings.

Michael Foale, making his fourth spacewalk, is designated EV1. He is wearing the spacesuit with blue stripes. Alexander Kaleri, making his fifth spacewalk, is designated EV2. He is wearing the spacesuit with red stripes.

This will be the first International Space Station spacewalk since the resident crews were reduced from three to two people in the wake of the Columbia accident. Therefore, no one will be inside the station during the spacewalk. Space station managers have established a list of rules that would terminate the spacewalk and get the crew back inside to deal with failures of station systems should that occur.