NASA Poised To Focus Hubble Work on Deorbit
A preliminary design review of the proposed robotic mission to service the Hubble Space Telescope did nothing to convince NASA to go forward with that option for refurbishing the popular spacecraft and installing two new instruments.
A NASA official said the agency still is moving forward with plans to conduct a so-called de orbit mission, deployment of a robotic spacecraft that would be used to equip Hubble so it can be guided into the ocean when the agency decides to retire it.
NASA Administrator Sean O’Keefe promised in 2004 to study the possibility of robotic servicing mission to Hubble after members of Congress and the scientific community complained bitterly about his decision to cancel a planned space shuttle mission to refurbish the popular space telescope.
The intensive preliminary design review for the proposed robotic servicing mission, which was held at the NASA Goddard Space Flight Center in Greenbelt, M d., involved volumes of technical data and more than 200 experts from NASA and aerospace industry contractor teams.
Intensive work has been underway at Goddard since last year to develop the tools, technology and procedures for a tele robotic servicing of Hubble. That NASA-contracted effort has been led by MD Robotics of Brampton, Ontario and Lockheed Martin Space Systems of Denver.
“The NASA position is [that] we are not contemplating continuing the tele robotic servicing mission,” said Mark Borkowski, the space agency’s program executive for the Hubble Robotic Servicing Mission, who also led the review, which was conducted the third week of March. “We are planning to convert to a de orbit-only mission.”
The de orbit mission would involve sending a robotically-controlled liquid-fueled motor to dock with the telescope. Once ignited, the engine would push the huge observatory into a controlled nose-dive into a remote ocean spot.
Senior NASA and industry officials involved in the Hubble program said that the de orbit mission is expected to cost $600 million to $700 million. Estimates for robotic servicing, the same officials said, are $1.3 billion to $1.5 billion.
Borkowski said the Goddard and industry team did a “super job” preparing for the preliminary design review. But he also noted that the view of an earlier review of Hubble servicing options by the National Academy of Sciences had already concluded that the chance of success for a robotic makeover of Hubble was remote.
“Now we’re going to go through a very deliberative decision process here [at NASA Headquarters]. We will listen to what people have to say,” Borkowski said.
“We don’t want to sound like we’re irrationally inflexible,” he added, “but at this point we don’t see a likelihood that there is some new information out there that’s going to cause us to have a revelation. What we saw was impressive, but not revelatory.”
Borkowski said the review will enable NASA to make an informed decision about how to proceed.
“We now have a job here in the agency to collect all that information and to make a good comprehensive, deliberative decision about how to convert the mission to deorbit only,” he said.
Insiders close to the Hubble servicing effort, however, said that significant progress has been made in readying telerobotic gear. Furthermore, adding more time onto Hubble’s life by finessing gyroscopes and better battery management adds up to less pressure in readying a robotic visit.
A preliminary design review is normally NASA’s first formal assessment of a program’s progress before approving the start of detailed design work. But in the case of the Hubble robotic servicing effort, NASA conducted the review after already deciding against saving the telescope. NASA’s 2006 budget request, sent to Congress in February, included no money for a Hubble repair mission of any kind. NASA officials said at the time that the agency would concentrate instead on preparing a de orbit-only robotic mission.
But a protest by Sen. Barbara Mikulski and Rep. Steny Hoyer, two Maryland Democrats who wield considerable influence over NASA’s budget, threw a new twist into the Hubble saga, as did President George W. Bush’s nomination of Mike Griffin to become the next NASA administrator.
Mikulski and Hoyer, both senior members of the Senate and House appropriations committees respectively , warned NASA in March that they expect the agency to heed the wishes of Congress and keep working toward a Hubble rescue. Congress late last year directed NASA to spend $291 million in 2005 preparing a Hubble repair mission. Until NASA hears otherwise from Congress, Mikulski reminded the agency, it is obligated to spend every penny of that amount as directed.
Senior NASA officials, including Borkowski, said a formal redirection of the Hubble robotics work is not expected before May.
Griffin is expected to be sworn in by then (his Senate confirmation hearing is slated for April 12), and industry sources who know him said the incoming administrator does not share O’Keefe’s view that sending a shuttle crew to Hubble is too dangerous. Whether that means Griffin will reinstate a shuttle servicing mission, they said, remains to be seen.
Without servicing, Hubble is expected to last perhaps until mid-2008, when its gyroscopes are predicted to fail.
To reach that 2008 date, there is now talk of turning one of Hubble’s three working gyros off. A two gyro option appears workable, while maintaining the telescope’s roster of science looks into the universe. That third gyro would be placed in storage mode, brought on line in the event that one of the operating gyros breaks down. Senior Goddard officials recently signed off on the change, which is now awaiting NASA Headquarters’ approval.