Just two days later, Mikulski appeared to have won an important battle when NASA agreed to an outside study of the Hubble issue lead by the National Academy of Sciences. But later that same day, during a meeting with reporters, NASA Administrator Sean OKeefe said that as long as he remains in charge of NASA, the chance that a shuttle will be launched to Hubble are slim to none.

I will not under any circumstances authorize the conduct of a mission like this thats not in compliance with the [Columbia Accident Investigation Board] recommendations, OKeefe said.

Mikulski, who is the ranking Democrat on the Senate Appropriations subcommittee that oversees NASAs budget, accused  OKeefe March 9 of making a unilateral decision to let the observatory die prematurely against the wishes of astronomers.

I believe that the future of Hubble should not be [decided] by one man in a NASA back room without a transparent process, Mikulski said, adding that she would continue working to bring the best advice possible to bear on possibly reversing the decision.

Mikulskis case for an outside review of the Hubble servicing mission was bolstered by none other than retired U.S. Navy Adm. Harold Gehman, the chairman of the Columbia Accident Investigation Board.

OKeefe, in an effort to mollify Mikulski, had asked Gehman in late January to review the Hubble matter and offer his unique perspective.

Gehmans offered that perspective in a five-page letter sent to Mikulski March 5.

In the letter, a copy of which was released to reporters March 11, Gehman concluded that a Hubble servicing mission may be slightly more risky then flying q shuttle to the International Space Station and said that only a deep and rich study of the entire gains/risk equation can answer the question of whether an extension of the life of the wonderful Hubble Telescope is worth the risk involved.

With Gehmans letter in hand, Mikulski and Sen. Kit Bond (R-Mo.), the chairman of the Senate Appropriations VA-HUD subcommittee, fired off a letter to OKeefe requesting that NASA contract with the National Academy of Sciences to conduct an independent review of the Hubble servicing mission and that in the meantime preparations for the mission continue. Mikulski and Bond also asked General Accounting Office, the investigative arm of Congress, to study NASAs decision to terminate the servicing mission and to report back on what it would cost to conduct such a mission in full compliance with the Columbia Accident Investigation Boards safety recommendations.

OKeefe, appearing before Bond and Mikulski during a March 11 NASA budget hearing, agreed to bring the National Academy of Sciences into the picture provided that the scope of the review be expanded to include an assessment of some of the proposals NASA has received for extending Hubbles life without flying a shuttle servicing mission.

NASA has been inundated with proposals for keeping Hubble in service beyond 2007 -- the telescopes current life expectancy based on the health of the its batteries and gyroscopes -- since putting out a call for ideas in February.

OKeefe also sought assurance from Mikulski as a precondition of commissioning the study that full compliance with the Columbia Accident Investigation Boards safety recommendations would guide any review of the Hubble servicing mission.

Mikulski told reporters after the hearing that while astronaut safety is paramount in any decision about Hubble, it is also her expectation that the National Academy will give the shuttle servicing mission a fair and full review, not rule it out from the start.

Back at NASA headquarters, OKeefe told reporters that he remains convinced that sending a shuttle to Hubble, given what NASA now knows about the vulnerability of the vehicle, would be fundamentally irresponsible.

He also gave his most detailed defense to date of his Hubble decision. A shuttle sent to Hubble, he said, has only one way to inspect itself for damage an instrumented boom that is still in development. Should that boom not work once on orbit, a Hubble crew would have no other way to ensure that their orbiter was not damaged during launch. A shuttle visiting the station, on the other hand, has a number of other inspection options at its disposal, including the possibility of conducting a spacewalk. OKeefe also said it deeply troubles him that a Hubble repair crew finding itself on orbit in a crippled shuttle beyond repair would have only one option for getting back home a never before attempted shuttle to shuttle rescue that would have two weeks at most to get off the ground. A crew stranded at the station, he said, would have 90 days to either repair their damaged shuttle or wait for a rescue.

OKeefe said he stands by his decision, hard as it is. Its the most unpopular decision I could have made but theres nothing here that says you do this job for popularity, he said.

Scientists and officials at the Baltimore-based Space Telescope Science Institute (STScI), which operates Hubble for NASA, applauded Mikulski for her support and said they have not lost hope even though some acknowledged it could take a miracle for Hubble to receive a stay of execution.

Mikulski is not alone in her crusade to save Hubble. Sen. Sam Brownback (R-Kans.), the chairman of the Senate Commerce science, technology and space subcommittee, said in a recent interview he favors repairing Hubble even if that means NASA has to cut back its space station plans to accommodate the mission.

A resolution introduced in the House of Representatives by Rep. Mark Udall (D-Colo.) to save Hubble continues to attract co-sponsors. Five more members have signed on since Udall introduced the resolution with seven co-sponsors March 3. And Rep. Dana Rohrabacher (R-Calif.), chairman of the House Science Committee, although he has not signed on to Udalls resolution, said he wants to see NASA go through with the mission.

Meanwhile, Hubble made its own case March 9  for its unsurpassed ability exploring the universe. STScI Director Stephen Beckwith unveiled the deepest photographs ever taken of the cosmos, the results of the Hubble Ultra-Deep Field. Researchers said the images likely contain the most distant galaxies ever recorded, and clearly visible are a host of baby galaxies in odd shapes and strange contortions that astronomers around the world are racing to comprehend.

Unlike many scientific results, which are hoarded while a handful of deeply involved scientists scrutinize them for well-deserved rights to first publication, Beckwith released the data to all scientists at once, and essentially told them to have a ball.

At Beckwiths side was Mikulski, who sent a letter Jan. 21 asking OKeefe to reconsider his Jan. 16 decision not to conduct Servicing Mission 4, which in 2006 would have extended Hubbles life to the end of the decade and even improve its capabilities with the installation of new instruments.

Instead, with its batteries dwindling and gyroscopes failing, Hubble could be rendered useless as early as this year or, more likely, sometime in 2007 without a servicing mission.

I think its just amazing, Mikulski said of the new photograph, which contains about 10,000 galaxies, a handful of which probably date back to when the universe was a mere 300 million to 500 million years old.

This is why I will continue to stand up for Hubble, Mikulski said.

Mikulski echoed the concerns of astronomers that OKeefe made his decision to cancel the servicing mission without taking the pulse of the astronomical community. Though OKeefe said the decision was based solely on astronaut safety, astronomers have suspected that Hubble is instead the first casualty of U.S. President George W. Bushs announced vision to reinvigorate human spaceflight, and that the endeavor to put humans back on the moon will come at the expense of science.

Mikulski, who had previously said she would accept Gehmans recommendation, changed that stance March 9.

I wont stop there, Mikulski said. I will continue to pursue getting the best advice possible.

Beckwith said he was pleasantly surprised at Mikulskis renewed determination. All of us were tremendously encouraged, because this is a big shift in the direction of, I dont care what Gehman says, he said of Mikulskis comments.

Beckwith is also amazed at the public support shown for Hubble and the fact that reporters keep writing news articles and editorials about the observatorys planned demise many, many news cycles into the situation.

And hes encouraged by a bill introduced in the U.S. House of Representatives last week by Rep. Mark Udall (D-Colo.), urging NASA to establish an independent panel of experts to review the Hubble decision.

Things are going our way right now, Beckwith said. A lot of people at this institution still think a miracle could happen.

He is realistic, however, knowing that the decision rests with NASA. His team is busy planning how to maximize Hubbles observations on the assumption that it has just two to four years left. They are also working on ways to extend battery life and operate on two gyroscopes instead of three, in an effort to ensure Hubbles productivity into at least 2007.

Beckwith stressed, though, that scientists are working on ways to keep the telescope under control even if the batteries dwindle beyond the point of supporting useful science, and that engineers have not yet figured out what would actually happen when the batteries fail.

I think its just too early to know, he said. But he added: Within the project, all of us who know this telescope are scared to death that it will wind up in a tumbling state that would be exceedingly challenging to retrieve under any circumstances."

The March 9 unveiling of the Ultra Deep Field images underscored just how important Hubble is to scientists. (The announcement was planned in December, prior to OKeefes decision about the fate of Hubble).

These sorts of results show how spectacular and unique Hubble is, Garth Illingworth, an astronomer at the University of California, Santa Cruz, said in an interview.

In fact, the photograph was made possible only because astronauts journeyed to the observatory in 2002, repairing its infrared camera and affixing a new visible-light camera, Illingworth points out. The two instruments were combined to make images of the identical space in the new project.

They made Hubble way better than its ever been, he said of the astronauts. Its a whole new spacecraft. Thats what these servicing missions are about.

A planned upgrade to Hubbles infrared camera would be 10 times more powerful than the current one, and the instrument is already built.

If the servicing mission could somehow be resurrected, as Illingworth and other astronomers hope, the new infrared capability would allow researchers to re-survey the Ultra Deep Field to characterize the distant galaxies. Instead of just knowing how big they are, astronomers could learn what they are made of. The new camera would also allow a broader look at the very distant universe, through additional surveys, helping theorists better understand how those early galaxies formed and evolved.