Endeavour closes in on station Alpha

For 8:15 a.m. EDT Saturday, April 21

Shuttle Endeavour is several thousand feet away from space station Alpha and is on course to dock with the orbiting outpost about 9:32 a.m. EDT.

Radio contact has been made between the shuttle and the station and spirits are high.

The shuttle's computers are essentially flying the orbiter right now, but soon after 9 a.m. commander Kent Rominger will take manual control of the flying duties and pilot the vehicle in for docking.

The Endeavour crew reported seeing the station for the first time more than an hour ago and Alpha now appears as a bright star at night and a beautiful spacecraft in the day.

For 9 a.m. EDT Saturday, April 21

Endeavour is now 430 feet away from the International Space Station and the gap is closing with every minute.

Docking of the shuttle and the outpost is now expected at 9:39 a.m. EDT.

Mission Control in Houston has given a formal go to the Endeavour crew for docking. Commander Kent Rominger is at the controls for this final phase of the approach.

For 9:40 a.m. EDT Saturday, April 21

The docking of Endeavour and station Alpha is taking a little bit longer than first planned. The two ships are now expected to be joined about 10 a.m. EDT.

There are no problems reported and shuttle commander Kent Rominger is under no constraints to dock at any specific time.

You can still watch the docking right here on SPACE.com.

For 10 a.m. EDT Saturday, April 21

Shuttle commander Kent Rominger safely docked Endeavour to the International Space Station this morning, bringing the two craft together for the ninth time as they circled some 243 miles above Earth.

The joining was officially marked at 9:59 a.m. EDT as the orbiting complex flew over the South Pacific.

This two-day chase of the space station began Thursday with Endeavour's launch from Kennedy Space Center and everything went well with the rendezvous and docking procedures.

Although now connected, the seven crewmembers aboard Endeavour will not join the three Expedition Two crewmembers aboard Alpha until Monday, after a scheduled spacewalk on Sunday to install a Canadian robot arm on the station is complete.

For 6 a.m. EDT Sunday, April 22

All is going well onboard shuttle Endeavour and the International Space Station, which were docked together without incident on Saturday.

The new Canadian robot arm is on the move this morning and preparations for the first spacewalk of the mission are on schedule.

Initial installation of the Canadarm2 using the shuttle's robot arm to connect a Spacelab pallet to the station is almost complete and the two spacewalkers are in their suits getting ready to begin a six-hour work sortie outside about 7:21 a.m. EDT this morning.

During this upcoming spacewalk Scott Parazynski and Chris Hadfield will continue with the Canadarm2 installation effort by manually unfolding the 57-foot-long arm. They also will help install a new UHF antenna onto space station Alpha.

You can watch NASA TV coverage of today's activities right here on SPACE.com.

For 6:55 a.m. EDT Sunday, April 22

The Spacelab pallet holding Canada's new robot arm is securely attached to space station Alpha.

Pilot Jeff Ashby operated the shuttle's robot arm to lift the pallet from Endeavour's cargo bay to an attach point on the Destiny science lab.

That repositioning took a little longer than expected, so today's spacewalk to continue installing the Canadarm2 is now expected to begin about 7:50 a.m. EDT or so, about a half-hour later than planned.

Canadian astronaut Chris Hadfield and Scott Parazynski will spend some six hours working outside Endeavour and Alpha.

You can watch NASA TV coverage of today's activities right here on SPACE.com.

For 8:10 a.m. EDT Sunday, April 22

Astronauts Chris Hadfield and Scott Parazynski officially began their spacewalk at 7:45 a.m. EDT and both EVA crewmen are now working outside, getting set up for the six hours of tasks ahead.

History already has been made: Canadian Space Agency astronaut Hadfield today becomes Canada's first spacewalker.

The two main jobs for the spacewalkers is to help continue with the installation and assembly of the new Canadarm2 -- which was attached to the Destiny science lab earlier this morning by pilot Jeff Ashby using the shuttle robot arm -- and the installation of a new UHF radio antenna on the station.

You can watch NASA TV coverage of today's activities right here on SPACE.com.

For 12:15 p.m. EDT Sunday, April 22

Endeavour's first spacewalk is now four-and-a-half hours old and so far things are going very well, with only a couple of small problems.

Astronauts Chris Hadfield and Scott Parazynski started their spacewalk at 7:45 a.m. EDT and quickly went to work installating a new UHF radio antenna and unfolding the Canadarm2.

Things slowed down a bit when Hadfield's left eye began watering, possibly because a speck of some anti-fog soap might have floated into his eye. Increasing the airflow into the helmet helped alleviate the trouble.

And in the past few minutes there was some trouble reported with tightening some bolts that will make the Canadarm2 rigid in its fully deployed position. But that difficulty appears to be solved and the banter between the spacewalkers is upbeat and playful.

There is some talk of adding some additional tasks to today's spacewalk to get ahead on work planned for Tuesday's spacewalk.

You still can watch NASA TV coverage of today's activities right here on SPACE.com.

For 3:00 p.m. EDT Sunday, April 22

The first of two planned spacewalks during shuttle Endeavour's stay at the International Space Station is complete and astronauts Chris Hadfield and Scott Parazynski are safely inside the orbiter airlock.

The pair spent seven hours and 10 minutes working around space station Alpha installing a new UHF radio antenna and deploying the new Canadarm2 robot arm, which is now operating under the command of the Expedition Two crew and was first moved on its own power at 2:54 p.m. EDT.

Everything went extremely well during the extravehicular activity. What few problems came up were quickly handled and the spacewalkers were able to complete all their tasks. A second spacewalk is planned for Tuesday.

On Monday a series of additional tests will be performed on the Canadarm2, including the first "step off" maneuver in which the arm will grab a special fixture on the Destiny science laboratory and then release itself from the other end.

Meanwhile the shuttle robot arm will be used to lift and attach the Italian Raffaelo supply module into place against the Unity module.

Also planned for Monday is the first official hatch opening and greetings between the Endeavour and Alpha crews.

For 5:30 a.m. EDT Monday, April 23

All ten humans flying in space right now finally got their chance to greet each other with warm hugs this morning as the hatches between shuttle Endeavour and space station Alpha were opened for the first time at 5:25 a.m. EDT.

The ten include representatives from the United States, Canada, Italy and Russia.

First order of business was a safety briefing to the shuttle crew by Expedition Two commander Yuri Usachev.

That will be followed by planned work today that includes the first major tests of the newly installed Canadarm2 and the attachment using the shuttle's robot arm of the Raffaelo supply module to the station's Unity node.

Later today the hatches will be closed again so that the shuttle can lower its air pressure in support of a second planned spacewalk on Tuesday.

The critical Canadarm2 tests are expected to begin within the next hour or so.

For 12:30 p.m. EDT Monday, April 23

It's been a busy and productive morning for the crews of space shuttle Endeavour and space station Alpha.

Following the hatch opening between the two vehicles at 5:25 a.m. EDT and a hearty round of welcoming hugs and handshakes, the ten crewmembers went off in different directions to complete the two major tasks of today.

The first was a check of the robot arm dubbed Canadarm2 that was installed yesterday. Today the space station crew opened up the arm and tested its various joints, and then grappled a fixture on the side of the Destiny science lab that will be the arm's new anchor point for the next year or so.

Later in the mission the other end of the arm will pick up the Spacelab pallet it is attached to and hand the pallet off to the shuttle robot arm after performing another series of tests.

The second main job accomplished today was the attachment of the Italian Raffaello supply module to an open port on the station's Unity node. The shuttle's robot arm was used for this effort in lifting the canister from Endeavour's cargo bay and attaching it to the station about noon.

The module contains about a ton of supplies for the crew as well as some new equipment racks for Destiny. The unloading is scheduled to begin tomorrow just a couple of hours before a second spacewalk is scheduled.

Because of the spacewalk, the hatches between Endeavour and Alpha will be closed again later today so that Endeavour's cabin air pressure can be lowered to support the spacewalk. This makes it easier by taking less time for the two spacewalkers to pre-breathe pure oxygen before stepping outside.

For 7:30 p.m. EDT Monday, April 23

Anxious to get started on unpacking the Italian Raffaello supply module, the crew aboard the International Space Station opened up the hatches to the canister tonight instead of when planned tomorrow morning.

Expedition Two flight engineer Jim Voss reported that ingress into the Multi Purpose Logistics Module -- one of three provided by the Italian Space Agency -- was complete at 7:13 a.m. EDT, according to NASA spokeswoman Eileen Hawley.

Although jumping into the unstowage work early, tomorrow's plans for when the second planned spacewalk is to begin won't change, she said. The spacewalk remains scheduled to start shortly after 9 a.m. EDT.

Raffaello was carried into orbit inside Endeavour's cargo bay and then today was lifted by the shuttle's robot arm into place against the Unity node of the space station Monday afternoon. The original timeline called for ingress at 5:26 a.m. EDT Tuesday.

Meanwhile, Endeavour's crew have returned to the shuttle and closed the hatches between the orbiter and station to support Tuesday's spacewalk.

Among the crewmembers is Italian Space Agency (ASI) astronaut Umberto Guidoni, who before launch received a special blessing from Pope John Paul II, according to an ASI news release:

"The Supreme Pontiff takes joy in sending you his cordial salute, which he extends to the whole crew. Especially, he sends you a wish of peace, hoping that through such a courageous enterprise, it will reach space and contribute to increase real progress and ever more brotherhood and solidarity to humanity. With these sentiments, he gladly sends you his blessing, and will make special mention in his prayers for all."

For 7:15 a.m. EDT Tuesday, April 24

Preparations for this morning's planned second spacewalk are moving along more quickly than anticipated and NASA mission commenatator James Hartsfield reports that the EVA now is expected to begin about 8:30 a.m. EDT, almost an hour early.

Spacewalkers Chris Hadfield and Scott Parazynski are to spend more than six hours working outside connecting cables associated with the new Candarm2, disconnecting a no-longer-needed radio antenna and installing some spare electronics to the side of the station.

There was some consideration given to having the pair attempt a fix of a balky pin that was hindering operation of the electricity-generating solar arrays, but Mission Control reported to the crew this morning that trouble was taken care of through ground commands.

Meanwhile everything is going well inside Endeavour and the station, where the Expedition Two crew has begun unloading the Italian supply module after opening the hatch to Raffaello before going to bed last night.

For 8:45 a.m. EDT Tuesday, April 24

Astronauts Chris Hadfield and Scott Parazynski have moved outside Endeavour's airlock and have begun their second spacewalk of this STS-100 mission.

Official start time was 8:34 a.m. EDT.

Their first task is to connect some power, data and video cables to the attach point where the new Canadarm2 is fastened on the side of the Destiny science laboratory.

During the next six hours or so they will also remove an unneeded radio antenna and install a spare electronics box on the outpost's exterior.

You can watch the spacewalk live on NASA TV right here on SPACE.com. During the EVA, you can tell the two spacewalkers apart because Hadfield's suit has red stripes.

For 4:20 p.m. EDT Tuesday, April 24

The second of two planned spacewalks during Endeavour's STS-100 mission has concluded and Chris Hadfield and Scott Parazynski are safely inside the shuttle's airlock.

Official ending time was 4:15 p.m. EDT making the spacewalk duration 7 hours and 39 minutes.

Although taking an hour more than planned, the pair were able to complete all the objectives of the spacewalk, including hooking power, data and video cables to the new Canadarm2 on the end where the arm is attached to the Destiny science lab, removal of an unneeded radio antenna and the installation of a spare electronics box outside the outpost.

The next major event of the mission is set for tomorrow when both the new station Canadarm2 and the shuttle's robot arm will be operated together to pass the Spacelab pallet that carried the new arm into space back into the cargo bay of Endeavour.

The event will mark the first such dual-use of robot arms in space.

At the same time work will continue to empty an Italian supply module that is temporarily attached to the station.

For 8:30 a.m. EDT Wednesday, April 25

A problem with a computer inside Space Station Alpha is delaying plans to further test the new Canadarm2 that was installed at the outpost this week by the visiting crew of Space Shuttle Endeavour.

Apparently the computer that is to control the next series of robot arm checks cannot access the files needed to execute the plan.

Two other computers are available and can be configured for the work, but that effort will take at least another 90 minutes or so, according to mission commentator James Hartsfield.

So as Mission Control troubleshoots the problem and replans the rest of the day, the crew aboard the outpost have turned their attention to other tasks, including the continuation of unpacking the Italian supply module.

For 11:45 a.m. EDT Wednesday, April 25

Tests of the new Canadarm2 and the handoff of a Spacelab cargo pallet from the new arm to the shuttle arm are still on hold while flight controllers continue to troubleshoot a problem with a computer on the space station.

It is increasingly likely that the robot arm operations will be delayed until Thursday to give controllers time to solve their problem, which is now more widespread than first believed.

Apparently the computer network onboard the station cannot access a collection of programs and files that are necessary to run many of the outposts systems, including the robot arm.

There have been communication glitches between the station and the ground as a result of this problem.

As if that weren't enough, the Russian carbon dioxide removal system has shut down on the station -- a problem unrelated to the computer difficulty, yet still a concern. Back up lithium hydroxide canisters in the station and shuttle are scrubbing the unwanted gas from the air.

Managers expect to make a decision shortly.

In the meantime, other operations are continuing including unloading the Raffaello supply module and eventually an orbit-raising maneuver using the shuttle Endeavour's steering thrusters.

For 8 p.m. EDT Wednesday, April 25

Mission Control is working overtime tonight to solve a computer problem on the space station that is forcing changes in the flight plan and prompting managers to begin considering adding another day to Endeavour's mission.

The trouble with the computer is complicated, both for journalists to explain -- let alone understand -- and for NASA's team of flight controllers to solve. So far little progress is being made by either group.

The problems first started about 24 hours ago when telemetry coming from the station suddenly stopped. It is this lack of communication from the computers that seems to be the most serious symptom of the difficulty.

The computers in question are the main command and control devices for the U.S portion of the station, obviously something that is critical to the health of the crew and the station that you don't want failing.

Flight controllers reported tonight that if the problem could not be solved before Endeavour departs -- or if a shuttle had not been present at all -- the crew would be in no danger and they could safely live and operate the outpost from the Russian modules.

With the initial discussion of adding a day to the mission, the logical result of that move -- if eventually approved -- might result in a one-day delay to the launch of the Soyuz taxi flight from the Baikonur Cosmodrome in Kazakhstan.

Interest in that otherwise routine mission is high because of the presence on the Soyuz crew of U.S. businessman Dennis Tito.

If controllers are successful in solving the problems while the crew sleeps tonight, the main task for Thursday will be to continue testing the new Canadarm2 -- the so-called "Big Arm" compared to the shuttle's "Little Arm. The operation would include using both arms to hand a cargo pallet from one to the other in another space first.

More should be known when the crew is awakened about 3:40 a.m. EDT.

For 7 a.m. EDT Thursday, April 26

Things are looking brighter on the joined shuttle and station complex this morning as Mission Control is making progress on solving the computer problems that have thrown the mission into a mode of replanning and troubleshooting.

About an hour after the crews were awakened about 3:40 a.m. EDT, the ground was able to restore the situation to near normal, although they still do not understand what caused the problem in the first place.

If things remain stable and controllers have confidence they are making progress on figuring out what happened then today's mission plan will include the robot arm operations originally planned for Wednesday.

That plan includes the new Canadarm2 -- or Big Arm -- handing a cargo pallet off to the shuttle's robot arm, now called the Little Arm, about 9:20 a.m. EDT or so.

Everything remains tenatative, however. We will continue to update this page first as events warrant.

For 8:30 a.m. EDT Thursday, April 26

Mission Control has radioed up a proposal to the Endeavour and Alpha crews that would call for another 24-hour delay in working out the new Canadarm2 on the station so that troubleshooting and confidence-building can continue with the outpost's three command and control computers.

Flight controllers appear to be well on their way to solving the computer problems that first cropped up late Tuesday and has since scrambled everyone's plans for the week. A key moment came this morning about 4:40 a.m. EDT when station flight engineer Susan Helms used a laptop to check on the station's systems and found that one of the three computers was working normally.

Subsequently, Mission Control was able to restore their insight into the computer system, apparently by establishing a link through Helms' laptop. Troubleshooting moved quickly from that point and the situation has dramatically improved.

Nevertheless, mission managers would like to take today to make sure everything continues to operate well and that more research is done to understand why the trouble happened in the first place.

As a result, it is likely that the duel robot arm operations will be delayed another day to Friday and in the meantime work will wrap up in the Raffaello supply module, its hatches closed and the shuttle's robot arm be used to return the canister to Endeavour's cargo bay late this afternoon.

That's the thinking at this hour, but events have evolved rapidly this morning so stay tuned to this page for the latest.

For 12 p.m. EDT Thursday, April 26

Here's the way NASA is explaining the latest developments onboard the joined shuttle-station complex:

Good news greeted space station flight controllers this morning when, shortly after awakening, Expedition Two flight engineer Susan Helms reported that the International Space Station computer systems may be returning to normal.

Working at a laptop computer aboard the station that serves as the crew's primary interface with the station's United States' command and control computer system, Helms relayed the good news about 3:45 a.m. Shortly afterward, Helms performed a series of troubleshooting steps that restored the ground's ability to monitor and send commands to the station's U.S. systems.

Space station flight controllers then sent commands that have put the station's systems in a better configuration in the event computer problems recur today. They also sent commands that transmitted data to the ground from the station computers to allow technicians to thoroughly analyze their hardware and software as part of the investigation that is under way to determine the cause of the computer problems.

Today, the astronauts and cosmonauts aboard Endeavour will continue joint work to reload the Raffaello logistics module with unneeded station equipment and supplies for return to Earth. The crews have completed unloading the 4,000 pounds of equipment that Raffaello carried to the station. While the reloading of Raffaello takes place, flight controllers will continue their analysis of the station computers. The station command and control computer brought on line early this morning has continued to be fully functiional and operate normally throughout the day. Controllers are working to bring another such computer online as a backup system later today. The recovery of the one command and control computer during the night is believed to have resulted from an automatic sequence aboard the station that powered each of the three command and control computers on and off in an attempt to bring them on line. The other two computers remained off line, however.

Given continued success with the computer recovery, the shuttle and station crews will resume work with the station's new Canadarm2 and the shuttle's robotic arm on Friday, handing off a 3,000-pound Spacelab Pallet from the station arm to the shuttle arm to store the pallet back in Endeavour's payload bay. A practice run with the new station arm to rehearse moves the arm must make during the next shuttle assembly mission to the station to attach a new airlock also will be conducted on Friday.

A second reboost of the station's altitude remains planned for later today. It will be an hour-long jet firing by Endeavour that will raise the complex's altitude by almost 41/2 miles. The two spacecraft are now orbiting the Earth every 92 minutes at an altitude of 243 statute miles. The next status report will be issued this evening at the end of the crews' day or as events warrant.

For 8 p.m. EDT Thursday, April 26

NASA mission managers have extended shuttle Endeavour's stay at the International Space Station by one day.

Landing, as a result, is also delayed one day. Endeavour is now scheduled to return to the Kennedy Space Center on Monday, May 1.

Based on earlier words from mission officials a single extension day of the shuttle mission would not delay launch of the Soyuz taxi flight at 3:38 a.m. EDT Saturday.

We will post more information as soon as we are able.

For 8:30 p.m. EDT Thursday, April 26

The news seems to change with every orbit around the Earth.

Mission Control has just informed the crew they plan to extend Endeavour's stay at the International Space Station a total of two days.

Undocking now will come on Monday and landing back in Florida on Wednesday.

Based on earlier comments from flight managers it's all but assured that the Soyuz taxi flight that includes space tourist Dennis Tito will also be delayed at least a day, but there is no official word yet from the Russians on that delay.

We will be posting a new wrap up story within the hour.