On orders from the White House, NASA's next budget reportedly will scuttle as too costly all proposals to repair and upgrade the Hubble Space Telescope with a manned shuttle mission or robots.
If upheld by Congress, the decision would mean that the space observatory is likely to suffer gyroscope breakdowns or battery failures that would cripple it by 2007.
Sen. Barbara A. Mikulski, a Maryland Democrat who has strongly supported the space telescope program, vowed over the weekend to continue her fight to save the Hubble.
NASA Administrator Sean O'Keefe announced a year ago that he was canceling the planned fifth and final shuttle servicing mission to Hubble because of safety concerns raised by the Columbia Accident Investigation Board, chaired by Adm. Harold W. Gehman Jr.
The mission would have extended the space telescope's expected lifetime until 2012 and greatly expanded its scientific capabilities.
In August, in a pep talk that drew cheers from NASA and contract workers at the Goddard Space Flight Center, O'Keefe urged scientists and engineers there to press ahead with development of a robotic mission to save the Hubble. An interim report on the feasibility of the plan is due in March.
According to a report first published last week by the online specialty publication Space.com, however, the White House has scrapped those plans as too costly in light of the National Aeronautics and Space Administration's efforts to get the shuttle fleet flying again and to complete the International Space Station.
Cost estimates to launch a manned or robotic rescue mission to the Hubble have ranged from $1 billion to $1.6 billion.
Instead, NASA will fund only a mission to safely deorbit Hubble as part of NASA's 2006 budget, which will be announced Feb. 7, according to the Web report, which cited unnamed government and industry sources.
"We have to wait and see what the president's budget has in it. We can't react until then," said Steven V.W. Beckwith, director of the Space Telescope Science Institute in Baltimore, which works with Goddard in controlling Hubble's scientific operations.
Beckwith said he is optimistic that support to save the telescope will swell again. Calls of support from Congress and the public have beaten back previous attempts to shelve the 15-year-old telescope.
"Hubble has gotten a lot of support since Mr. O'Keefe's announcement last year," Beckwith said, referring to the announcement to cancel a shuttle mission to service it.
The Space.com report said O'Keefe was told during a Jan. 13 budget meeting at the White House to scuttle the Hubble rescue effort. His official announcement, perhaps at his Feb. 7 budget presentation, would probably be one of the administrator's last official acts. O'Keefe announced last month that he will resign his NASA post to become chancellor of Louisiana State University, departing as soon as his successor is named.
Mikulski led a drive in Congress last year to save the Hubble telescope and to put the question to a panel of experts appointed by the National Academy of Sciences.
In December, the group issued a report concluding that the Hubble's capabilities are "unmatched by any other optical telescope currently operating or planned." A shuttle mission to repair and upgrade the orbiting observatory, the panel said, was the safest way to extend its exploration of the universe, with a greater chance for success than unproven robotics.
Congress then allocated almost $300 million to NASA to continue planning a Hubble rescue.
"It is essential that we have a safe and reliable servicing mission to Hubble that is consistent with the Gehman Commission and the National Academy of Sciences," Mikulski said. "I will continue to advocate for this mission. ... This is what the American people expect and deserve."
According to an analysis by the trade publication Science News, the Hubble is the top producer of discoveries among NASA's projects.
"Every time a high-level committee looks at this issue of servicing Hubble, each one says that this is feasible," Beckwith said, referring to the National Academy of Sciences report. "I am optimistic that when Congress takes a close look at NASA, they will determine that Hubble is well worth it."
Sun staff writer Frank D. Roylance contributed to this article.