Second spacewalk almost ready
Tuesday, March 5, 2002 at 1:10 a.m. EST

A quick update to say that the second spacewalk appears it will start in about 15 minutes.

Jim Newman and Mike Massimino are in their spacesuits, inside the airlock and ready to begin depressurizing.

You are invited to watch the spacewalk via our feed of NASA TV, available by clicking on the link above.

We will update again after the spacewalk begins and then every couple of hours after that.

What for the most part will be a very familiar spacewalk has begun in Earth orbit as astronauts Jim Newman and Mike Massimino are totally relying on their spacesuits for life support for the next seven hours.

The second of five planned spacewalks on this STS-109 mission officially began at 1:40 a.m. EST.

Nearly a repeat of Monday morning's spacewalk, this extravehicular activity will feature the replacement of the Hubble Space Telescope's port side solar array with new rigid solar wing that is slightly smaller, a little heavier and more efficient in generating electricity than its predecessor.

Unlike the first EVA, however, this morning's venture outside also will include the replacement of a Reaction Wheel Assembly, or RWA. The device helps Hubble point in space.

If you're watching this on NASA TV via our feed, which is available by clicking on the link above, you can tell the astronauts apart by the type of red stripe on their suits. Newman's will have broken red stripes, while Massimino's will have diagonal red stripes like an old-fashioned barber pole.

We will update this page again in about two hours.

The Hubble Space Telescope sports a new look now that both of its solar arrarys have been replaced.

Working outside in Columbia's cargo bay, spacewalkers Jim Newman and Mike Massimino have removed Hubble's old port array and physically connected a new wing. Electrical connections and initial tests of the solar wing will follow.

Taking advantage of lessons learned from Monday morning's spacewalk, today's pair of workers are moving along in their tasks easily and are about 30 minutes ahead of schedule.

Next major task ahead: replacement of a Reaction Wheel Assembly, or RWA. The device helps Hubble point in space.

We will update this page again once that task is finished.

Spacewalking astronaut Mike Massimino has finished installing a new Reaction Wheel Assembly (RWA) unit, replacing a suspect unit that had a momentary glitch several months ago but otherwise was working fine.

Use in precisely pointing the Hubble Space Telescope as it makes observations, the RWA's on Hubble are critical for mission success so a replacement was added to this servicing mission.

With this task complete, Massimino and fellow astronaut Jim Newman are about 20 minutes ahead of the timeline for their spacewalk, so Mission Control will probably add a "get ahead" task to this sortie, which will probably last about another two hours.

Stay tune to this page for updates.

Astronauts Jim Newman and Mike Massimino are safely back inside a repressurizing airlock after spending seven hours and 16 minutes working outside on the Hubble Space Telescope.

The first part of the spacewalk was similar to Monday morning's effort outside, with Newman and Massimino replacing one of Hubble's solar arrays with a smaller, yet more powerful, electricity-generating wing.

Then as Newman did some work below, Massimino -- working from the end of the shuttle's robot arm, which was piloted by Nancy Currie from Columbia's flight deck -- replaced a suspect Reaction Wheel Assembly unit that is critical to Hubble's ability to make precisely pointed observations.

With both of those tasks complete, the crew found themselves about 20 minutes ahead of the timeline, so Mission Control ordered some "get ahead" tasks be accomplished, one of which included installing some insulating blankets over one of the telescope's bays.

Those efforts were followed by the usual daily clean up and a return to Columbia, with an official spacewalk end time of 8:56 a.m. EST.

The third spacewalk, set to begin about 1:27 a.m. EST Wednesday, is the most critical of the mission and will feature the task of completely shutting down Hubble, risking that it will not start up again.

We will be here to provide timely updates beginning at 1 a.m. EST Wednesday. In the meantime, we will be posting our wrap-up story of today's spacewalk shortly and then we'll see you back here again tonight.

A small amount of water has dripped out of John Grunsfeld's spacesuit, prompting Mission Control to order that Grunsfeld get into a different spacesuit and re-start the pre-breathing of pure oxygen.

Mission commentator Rob Navias reports this could delay the start of this morning's spacewalk by about an hour.

Stay tuned to this page for updates.

An unexpected water leak in John Grunsfeld's spacesuit has not only delayed this morning's spacewalk by at least two hours, but also is prompting mission managers to consider a variety of options that include delaying today's planned work to Thursday and doing Thursday's tasks today.

Advertised as one of the most complex and critical spacewalks in U.S. program history, the original plan today calls for Grunsfeld and fellow spacewalker Rick Linnehan to remove and replace a Power Control Unit (PCU) inside the Hubble Space Telescope.

So important is the PCU to Hubble and so risky is the act of replacing it that managers have likened today's spacewalk to performing a heart transplant in a human. In fact, to support the swap out, Hubble will have to be completely turned off for the first time in more than 20 years. And while turning off the observatory is a relatively easy task, turning it back on raises any number of fears among NASA officials.

In the meantime, Grunsfeld is moving quickly into a new spacesuit and will repeat his pre-breathing. NASA mission commentator Rob Navias now reports the beginning of the third spacewalk could come around 3:30 a.m. EST, or about two hours later than planned.

A complicated number of variables are being considered and we will update this page again when NASA announces its plans for the rest of the morning.

Mission Managers have decided to press on with the original plan of spacewalkers John Grunsfeld and Rick Linnehan replacing the Hubble Space Telescope's Power Control Unit (PCU), a risky procedure akin to performing a heart transplant on a human.

The beginning of the spacewalk is roughly targeted for 3:30 a.m. EST, about two hours later than planned. All activity related to the spacewalk, including the overall crew day, will be slipped to the right. The astronauts will work a longer day today, then sleep in on Thursday before starting the fourth spacewalk.

Hubble remains fully powered up and ground controllers remain ready to support the PCU swap out plan as intended.

Today's spacewalk was delayed when Grunsfeld's spacesuit started leaking water, probably because of a problem related to a flow control valve. Water is moved through tiny tubes within the suit to keep the spacewalker and the spacesuit electronics cool.

We'll stand by now for the clean up work to conclude and the crew to reset for another attempt at beginning the spacewalk, so our next update will come about 3:30 a.m. EST.

Better late than never, astronauts John Grunsfeld and Rick Linnehan have begun the third of five planned spacewalks for this STS-109 mission about two hours later than planned because of an earlier problem that forced Grunsfeld to don a new spacesuit.

Official start time of today's spacewalk: 3:28 a.m. EST.

Very soon the Space Telescope Operations Control Center at the Goddard Space Flight Center in Greenbelt, Md., is expected to begin powering down the observatory for the first time in its history. The potentially risky milestone is required so the spacewalkers can swap out the electronic heart of the telescope.

This is the 16th spacewalk staged to service Hubble. Fourteen different astronauts have participated.

You are invited to follow the spacewalk via our NASA TV feed by clicking on the link above. During today's extravehicular activity Grunsfeld's suit will have red stripes, Linnehan's suit is plain white.

We will update this page every couple of hours or so as required.

For the first time since it was first deployed into orbit on April 24, 1990, the Hubble Space Telescope sits within Columbia's cargo bay as an inert piece of metal and glass -- no power running through its systems. Hubble was turned off at 4:37 a.m. EST.

"Hubble is without a heartbeat," said NASA mission commentator Rob Navias.

The clock is now ticking toward what is certain doom for the great observatory unless power is restored to the telescope within about 10 hours. That's when the instruments and systems within Hubble would become too cold to restart.

The key task now is for Grunsfeld and Linnehan to replace Hubble's heart, the Power Control Unit that helps distribute electrical power throughout the telescope. Thirty-six connectors must be undone, a new PCU put in place and the 36 connectors re-attached.

Complicating the matter is that the PCU is one of the few components aboard Hubble that was never designed to be replaced or worked on in orbit by spacewalking astronauts.

Stay tuned to this page for updates, or you can watch the NASA TV feed by clicking on the link above.

Hubble's original Power Control Unit has been removed from the telescope as this third spacewalk continues with little trouble -- except that it started two hours late.

The new PCU is being carried up to the telescope at this writing and should be installed within the next hour or so.

It appears that everything is going well and that Hubble controllers should be able to begin powering up the observatory in plenty of time to avoid any damage to the telescope's electronics.

Stay tuned to this page for updates.

With today's spacewalk now five hours in duration, all continues to go surprisingly well as astronauts John Grunsfeld and Rick Linnehan work outside to replace the Hubble Space Telescope's electrical heart, the Power Control Unit.

Success for the replacement was declared at 8:19 a.m. EST as Grunsfeld finished attaching 36 cables to the new PCU.

Still ahead for the spacewalkers are tasks involved with reattaching cables to some fuses and batteries, which should go relatively quickly. Then Hubble controllers on the ground can begin an hours-long process of turning the telescope back on, a scary process for the Hubble program because this has never been done before.

Although engineering analysis shows everything should work fine, who among us hasn't seen an appliance that has worked fine for years suddenly fail after you turned it off -- for maintenance, or maybe a long vacation -- and then back on again.

As of this update, Hubble has been without power for nearly four hours. Power needs to be restored within about 10 hours before the telescope is in danger of not working again.

Stay tuned to this page for updates.

Electrical power has begun flowing through the Hubble Space Telescope again, but it will be several hours before everyone can breathe a sigh of relief that none of its critical systems or science instruments were damaged by the power outage.

After spacewalking astronauts replaced the Power Control Unit, ground controllers began turning on Hubble at 9:02 a.m. EST to make sure the PCU would work OK. It did and then the spacewalkers re-connected all of Hubble's batteries and then power was fed into the observatory from the shuttle Columbia.

Still ahead is several hours of reviving the various systems and instruments, so while the patient has a new heart and is off life support, we still don't know yet if the patient can use all of its arms and legs yet.

Meanwhile, astronauts John Grunsfeld and Rick Linnehan are beginning to clean up their work outside Columbia's cargo bay before heading back into the airlock to wrap up this third extravehicular activity. The end of the spacewalk is expected within the hour.

Our next update will come after the spacewalk is officially finished.

It's three down and two to go for Columbia's spacewalkers.

The third spacewalk of the STS-109 mission is now one for the history books, officially concluding at 10:16 a.m. EST after lasting six hours and 48 minutes.

Billed as one of the most complex and potentially risky spacewalks ever attempted, astronauts John Grunsfeld and Rick Linnehan pulled off the effort with relatively few problems, making it look easy as they replaced the Hubble Space Telescope's electrical heart with a new device that will last the rest of the observatory's lifetime.

The spacewalk began two hours late because of a problem with Grunsfeld's spacesuit that forced him to don a new suit before heading out the airlock.

Once begun, however, everything worked like clockwork as first the old Power Control Unit was disconnected from the telescope, removed and then replaced with a new unit, which has since proved to be working fine.

The transplant required that Hubble be turned off for more than four hours, and although power has since been restored and everything looks good at this point, it will still be several hours before Hubble program managers can say for sure that the power outage hasn't caused some damage to any of the critical systems or science instruments.

The next spacewalk is scheduled for early Thursday morning, with a probable start time of around 2:30 a.m. EST.