Astronauts with Hubble

Astronauts John Grunsfeld (left) and Richard Linnehan work on the Hubble Space Telescope during the last shuttle servicing mission in March 2002.

Courtesy NASA.

The stage is set for a showdown between NASA and the US Congress over the future of the Hubble Space Telescope (HST). On July 13th a congressionally mandated panel of the National Research Council recommended that the space agency keep open the option of sending another Space Shuttle crew to service and upgrade the orbiting observatory. This contrasts starkly with NASA administrator Sean O'Keefe's mid-January decision to cancel further shuttle missions to the telescope because of concerns about risks to the astronauts in light of last year's Columbia disaster.

O'Keefe's announcement was met with a tremendous outcry from astronomers, members of Congress, and the public. Eventually O'Keefe committed his agency to doing everything within its power and budget — short of flying a shuttle mission — to keep Hubble operating as long as possible. Without further servicing, the telescope will likely succumb to a battery or gyroscope failure sometime in 2007 or 2008. So NASA's chief agreed to look into the possibility of launching some type of robot to attach new power supplies and gyros. Meanwhile Senator Barbara Mikulski (D-Maryland), one of the telescope's strongest supporters on Capitol Hill, led a bipartisan effort to ensure that NASA's plans were subjected to a thorough review by independent experts.

The resulting high-level panel, the Committee on the Assessment of Options for Extending the Life of the Hubble Space Telescope, is chaired by Louis J. Lanzerotti of Bell Laboratories, Lucent Technologies, and the New Jersey Institute of Technology. In a letter to O'Keefe on behalf of the entire membership, Lanzerotti expressed concern that robotic space technology may not be ready in time to save Hubble. To service the telescope, a robot would have to rendezvous and dock with it, remove and replace complex equipment, and disconnect and reconnect electrical cables. None of these tasks have ever been done before robotically, though some are scheduled to be tested on a couple of Defense Department space missions over the next two years.

Moreover, says the Lanzerotti committee, replacing batteries and gyros isn't enough. Hubble "is arguably the most important telescope in history" because of its unprecedented scientific capabilities and its invaluable contributions to almost every field of astrophysics and planetary science. Many of the telescope's accomplishments have come from instruments installed by shuttle astronauts in the years since its 1990 launch. Two more new instruments — the Wide Field Camera 3 and the Cosmic Origins Spectrograph — have already been built at a combined cost of nearly $200 million and are expected to dramatically advance Hubble's scientific capabilities. In its July 13th letter, Lanzerotti's committee urged NASA to commit to installing these instruments during the next servicing mission, whether it ends up being carried out by humans or robots.

O'Keefe responded in a prepared statement: "We agree with the Committee's view that the Hubble Space Telescope is arguably the most important telescope in history. NASA is committed to exploring ways to safely extend the useful scientific life of Hubble." But he then went on to discuss only the robotic option. O'Keefe has consistently maintained that dispatching another Space Shuttle to Hubble is incompatible with his pledge to meet the requirements imposed by the Columbia Accident Investigation Board and the group overseeing the agency's return-to-flight efforts. Again, this contrasts with the view of the Lanzerotti committee, which wrote that "a shuttle flight to the HST is not precluded by or inconsistent with the recommendations from these two NASA advisory groups."

Lanzerotti's committee is continuing its study and expects to make a final report in late summer or early fall. The July 13th letter to O'Keefe was an interim report. Still, it has given astronomers hope because, as one insider put it, "it keeps HST in the 'game.'"

"I am delighted that a committee with such broad expertise in engineering and science believes the Hubble Space Telescope should continue its productive life through servicing," says Steven Beckwith, director of the Space Telescope Science Institute. "They identified two viable ways to service Hubble, and I hope very much that NASA will use one of these opportunities to keep Hubble at the scientific forefront for many years to come." Concerning the Lanzerotti panel's interim report, Beckwith adds, "This result is as definitive as I could have hoped for."


You must be logged in to post a comment.