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US space agency Nasa will announce the decision in February, ending plans to send a human or a robot repairman, the Washington Post reported. The service cost was expected to top $1bn, but has been cut from the federal budget request, sources told the paper. For 15 years Hubble has captured some of the most profound images of space. Previous services It was designed to be visited periodically by astronauts who would perform repairs and install new equipment. Astronauts have made servicing visits to the telescope several times, with a final servicing mission - now cancelled - due for 2006. Despite the funding cut, the telescope is not yet being shut down - just allowed to operate normally until wear and tear take their toll. Its original mission was supposed to last 15 years, and was extended to 20 years, with a projected end date of 2010. |
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Since its launch 15 years ago, it has captured some of the most profound - and widely distributed - images of the Universe. Its ethereal shot of a shimmering Eagle Nebula is as likely to be found on the side of a bus as in the pages of an astronomy textbook. And, like a celebrated icon, Hubble has now become the focus of controversy. Its future is up for grabs. And as scientists discuss how - even whether - to service the ageing telescope and prolong its life, the debate over using a human or a robot to do so has grown contentious. While the US space agency (Nasa) talks tentatively of sending robots to service Hubble, a panel of the National Research Council (NRC), the principal operating agency of the National Academy of Sciences (NAS), has recently recommended that astronauts make the repairs. Now, another vote has been cast in favour of sending humans to do the job. In a statement released on Tuesday, the American Astronomical Society (AAS), the largest professional astronomical organisation in North America, said it endorsed the NRC position. Nasa, it stated, should pursue a manned mission to repair Hubble and launch it as early as possible after the space shuttle is ready to fly again. The AAS called Hubble "a remarkable instrument for scientific discovery", and supported the NRC¿s conclusion that a shuttle mission presented the lowest risk. Is it safe? The NRC panel comprised a group of distinguished astronomers, engineers, former astronauts and Nobel laureates. Their December report concluded that an unprecedented robotic mission might not be developed in time to save Hubble, would be more technologically risky, and could critically damage the telescope. It also found that the differences between the risks faced by a crew to service Hubble and those of a single shuttle mission to the International Space Station (ISS) were small.
"[The NRC] came down very clearly saying that if you really care about the space telescope, then doing the shuttle mission is the best answer," Harvard University Astronomer and AAS President Robert Kirshner told the BBC News website. Congress directed Nasa to request a study from the NRC to look into HST servicing options after Nasa cancelled what was to be the fifth, and final, shuttle-servicing mission to the telescope. Nasa administrator Sean O'Keefe, citing safety concerns, announced the decision to cancel the shuttle flight shortly after President Bush announced his space initiative and said that shuttle flights would be used only to service the ISS, as a step to putting humans on the Moon and Mars. Since then, the space agency has looked at robotic options to repair Hubble's fading gyroscopes and batteries. The telescope is also slated for a new camera and spectrograph. With these repairs, Hubble's observing life could extend to 2013. Although it recently signed a contract with a Canadian firm, MacDonald Dettwiler (MD) Robotics, to develop a servicing robot, Nasa has not fully committed to a robotic mission. Hubble death At the AAS meeting in San Diego last week, in a session outlining the options for Hubble, Col Mark S Borkowski, Nasa Project Manager for Hubble Robotic Servicing, said that 2005 would be used to firm up a plan. "We have probably as many questions as you have about what is the future of Hubble, what is the best way to maximise the future of Hubble and what are our options," he said. The agency is investigating the feasibility and cost of developing a robotic mission, and also the alternative of leaving Hubble to its fate.
While the robotic technology developed by MD Robotics was encouraging, said Col Borkowski, it might neither justify its estimated $175-$300m price tag, nor be viable in time to save the telescope. A preliminary design review of the robot is scheduled for March, with a critical review to follow later in the year. Ultimately, he said, Nasa would decide whether a robot mission was worth it. Plan B is not to service Hubble and bring it down at the end of its observing life. In this case, a robot could also be developed to de-orbit the instrument. While Dr Borkowski stressed that the NRC recommendation of a shuttle flight would be a "key input" into the ultimate decision about repair, he also reiterated that Nasa had no plan to conduct shuttle servicing. A thorny subject This prompted pointed responses from some astronomers in the audience. Rodger Thompson, a University of Arizona astronomer and principal investigator of the Near-Infrared Camera and Multi-Object Spectrometer, which astronauts placed on Hubble in 1997, reiterated the cogency of the NRC finding. "I have to say that you - Nasa - have a solution in hand and you have not taken it. ' "You¿ve created your own problem by refusing to use the low-cost option with small incremental risk," Dr Thompson said. "It's really up to you to reverse that, and make the decision to do the shuttle mission." He later told the BBC News website that Hubble was specifically designed for shuttle servicing, and that four prior astronaut missions to the telescope were "very successful".
Dr Kirshner also asked the panel why, given that the best bet for saving Hubble was a shuttle mission, according to the NRC, "there was no planning at Nasa for a shuttle mission". "I didn't say there was no planning," said Col Borkowski, "I said there is no plan." If Nasa is parsing its words to both pursue a course of action for Hubble, and deftly keep its options open, it does so at time of great uncertainty and restructuring for the space agency. Nasa is shuffling priorities and funding to accommodate the President's back-to-the-Moon initiative and is in leadership limbo as Mr O'Keefe prepares to step down. Nasa officials said that the decision not to pursue a shuttle mission to service Hubble ultimately rested with Mr O'Keefe. "A new administrator will have final decision in where we go," said Nasa spokeswoman Susan Hendrix, of the Goddard Space Flight Center. Two out of three As the clock ticks for Hubble, the observing carries on. The telescope's science instruments are working well, with the exception of the Space Telescope Imaging Spectrograph (STIS), which shut down in August, said Rodger Doxsey, head of the Hubble Mission Office at the Space Telescope Science Institute (STScI), which operates Hubble for Nasa. While Hubble awaits its tune-up, Nasa scientists weigh options for battery and gyroscope conservation. "Our goal is to get the longest lifetime that we can," said Dr Doxsey. "We don't want to lose science waiting for the servicing to take place." The ultimate lifetime limiters for Hubble are its batteries, which, like those in a mobile phone, lose their ability to recharge over time. Without servicing, the batteries will give out in 2007-08. The gyroscopes keep the telescope stable, which anyone who has tried to steady a telephoto lens can appreciate. Hubble has six gyroscopes. Two have failed, but it needs only three to control it. Anticipating further failures, Nasa Goddard would test a control mode next month for science to proceed on two gyros, said Dr Doxsey. Astronomers petitioning for time with Hubble must consider the two-gyro mode in their proposals. Robotic dexterity Meanwhile, the plans for a robot mission are underway. The proposed candidate, designed by MD Robotics, is a slightly modified version of Dextre, the dexterous robot built to service the ISS. Looking like a human stick figure with arms akimbo and a long grapple arm in place of legs, the robot is designed for complex manoeuvres in space and has been tested at Goddard on a mock-up of Hubble. Its charge in space is to replace the telescope's batteries, change the connectors on the gyroscopes, and install two new instruments: the new Cosmic Origins Spectrograph, which is sensitive to very faint UV light, such as that from intergalactic gas in the early Universe, and the Wide Field Camera 3, optimised for infrared, ultraviolet and visible wavelengths. Dr Thompson said that, although he was impressed with the robot's performance at Goddard, an unprecedented robotic repair of Hubble was too risky to be pursued single-mindedly. Given that a return to flight was inevitable, he said, and that many flights were necessary to complete construction of the ISS, routing one to extend the life of a scientific instrument that has already proven so valuable was reasonable. "One flight to the Hubble Space Telescope will produce far more science than 25 flights to the ISS," he said. Great Hubble discoveries were still to come, agreed Dr Doxsey, and efforts should be made to encourage them. "We want to think twice about turning off a telescope that is in its prime," he said. |
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We have probably as many questions as you
have about what is the future of Hubble, what is
the best way to maximise the future of Hubble
and what are our options
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www.SaveTheHubble.com was established by University of Brasilia lecturer Fernando Ribeiro following the US space agency's decision to abandon the scope."I hope it will become a forum about Hubble's prospects and a launch pad (so to speak) for a campaign to save it." Left alone, Hubble, called the most important scientific instrument ever, could only survive another three years. Safety concerns Astronomers were stunned when Nasa's chief, Sean O'Keefe, decided on 16 January to cancel the fifth, and final, visit of the space shuttle to service the Hubble Space Telescope (HST). A service call is essential to ensure Hubble's smooth operation until the end of the decade. The telescope has only three working gyroscopes, down from its complement of six, and cannot afford to lose any more.
Dismayed astronomers understood O'Keefe's logic, but many pointed out that there would now be a gap of several years between the demise of Hubble and its replacement reaching orbit. They also wondered if there was any way to save the telescope. Noise from Brazil In Brazil, Fernando Ribeiro also wondered if Hubble could be saved. "The HST is such an important, complex, fascinating and cost/benefit effective instrument that it is hard to imagine someone could ever suggest it should be dumped into the ocean, let alone Nasa itself," he told BBC News Online.
Mr Ribeiro first heard about Hubble's demise from the internet. "I sat in front of the monitor and stared at it for several minutes recollecting all the facts I knew about Hubble; its planning, building, the flawed mirror, the device to fix it, the book I had: Gems of the Hubble. I thought about the loss it meant to the whole human race." So www.SaveTheHubble.com was born. "I imagined that it could be a good idea to build up a site where people could voice their feelings and ideas about the whole story. My role would be to put together as many references as I could about the struggle to save the telescope. "There has been an exponential growth of the public outcry in favour of the instrument, and it is just the beginning. Since the matter is obviously political, public pressure will certainly play a big role, especially in an election year." The petition will be sent to Nasa and US politicians. "Let the voters say: 'We don't want to go to the Moon! We want to go to infinity and beyond!'," said Mr Ribeiro. |
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On 16 January, he said that because of astronaut safety there would be no more space shuttle missions to maintain and upgrade the orbiting telescope. No more servicing would limit Hubble's life to approximately three more years. Mr O'Keefe has now asked Harold Gehman, who led the Columbia accident inquiry, to look into the Hubble issue. Rigorous review Following Mr O'Keefe's decision Senator Barbara Mikulski, whose home state of Maryland hosts the Hubble Space Telescope Science Institute, sent a letter asking him to reconsider his decision. In reply, Mr O'Keefe wrote: "I have asked Admiral Hal Gehman, Chair of the Columbia Accident Investigation Board, to review the matter and offer his unique perspective. "[He] has agreed to undertake this review and offer his view in a thoughtful and expeditious manner." In a statement Senator Mikulski said: "When someone is told they need major surgery, any prudent person would get a second opinion. "That's what I told Administrator O'Keefe and that's what he has agreed to do. Hubble has made so many extraordinary contributions to science, exploration, and discovery," she continued. "We cannot prematurely terminate the last servicing mission without a rigorous review." Inspect and repair Mr O'Keefe made the controversial decision because he decided that flying the shuttle anywhere other than to the International Space Station (ISS) was too dangerous following the Columbia disaster. If anything went wrong on a flight, the shuttle's astronauts would at least be able to wait on the ISS until a way was found to bring them down safely to Earth. But astronomers pointed out that Nasa would also have to plan for a situation in which the space shuttle got into space but could not dock with the ISS. In this scenario, Nasa would have to ensure that astronauts could inspect the shuttle, and perhaps repair it, without help from the ISS. It follows, therefore, the astronomers argue, if the shuttle can go into space without visiting the ISS, it should also be able to visit the Hubble telescope as well. |
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Nasa requested the report through the US National Academy of Sciences after being criticised for the decision to ban future shuttle servicing flights. The ban was deemed necessary because of new safety rules brought in following the loss of the space shuttle Columbia. The report says it is vital to repair Hubble by manned or unmanned missions. Astronauts or robots Nasa's January decision to cancel the fourth shuttle mission to service the ailing Hubble Space Telescope (HST) led to a welter of criticism from, amongst others, US politicians; and this prompted the agency to seek a second opinion. The full report, produced by prominent scientists and engineers from the National Academy of Sciences, is due in the Autumn but the panel has released some of its early thoughts. It says that according to its interpretation of the recommendations of the Columbia Accident Investigation Board (CAIB), it does not believe that a shuttle flight to the HST has been completely ruled out. Consequently, it does not want Nasa to foreclose the shuttle option to service the HST.
The panel says it would be happy to see the servicing done by either a manned mission or by a robotic spacecraft - just as long the HST is saved. Without further servicing, say astronomers, the HST is unlikely to survive for more than three or four years. The panel says a further servicing mission should include both the replacement of the present instruments with the two instruments already developed for flight - the Wide Field Camera-3 and the Cosmic Origins Spectrograph - as well as engineering objectives, such as gyroscope and battery replacements. Such a servicing mission, the report continues, would extend the life of this unique telescope and maximise its productivity. 'National treasure' In a statement on the Hubble report, Nasa's Administrator Sean O'Keefe said he deeply appreciated the panel's comments - but he gave no indication he would change his mind on manned servicing. "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. "The challenges of a robotic mission are under examination and we'll continue our exhaustive and aggressive efforts to assess innovative servicing options," he says. "Nasa will evaluate proposals we expect to receive shortly. Along the way, we'll keep options open to assure the best possible outcome. "The Hubble Space Telescope is a national treasure. Just as we are committed to meeting the recommendations and findings of the CAIB and returning the space shuttle to safe flight, we're committed to doing everything possible to safely extend the scientific life of this valuable asset." |
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NASA Told To Focus On Destroying Telescope Safely ANN has learned that NASA Administrator Sean O'Keefe has been told there are no funds to maintain or upgrade the Hubble Space Telescope, and that the only funds available will be those set aside attaching a thruster to the telescope in order to ensure a safe re-entry... and destruction... of the Hubble.
O'Keefe has not gone public with this, but sources told members of the space media that he may make the announcement on February 7 when the agency announces its FY2006 budget request.
The Administrator apparently was given the news on January 13 in a White House meeting with administration officials. The robotic and shuttle-based options to maintain and upgrade the Hubble were both expected to cost in excess of $1 billion. O'Keefe was allegedly told that the Hubble maintenance mission could not be put into the budget given NASA's other commitments, including the return to flight of the Shuttle fleet.
O'Keefe has not informed Congress about this turn of events as of yet -- but there appeared to be rumors around Capitol Hill that this was to happen.
However, this may not be the end of the line for the telescope, as some in Congress have suggested that the initial decision is nothing but a negotiating ploy, and that Congress may simply turn around and appropriate the funds necessary to keep the Hubble in operation.
