By Joel Achenbach
Washington Post Staff Writer
Saturday, May 23, 2009
NASA's triumphant mission to repair the Hubble Space Telescope this week has cracked open a policy rift within the space agency, with a top NASA scientist saying that the United States is on the way to losing the capability to do what it has just done so dramatically.
David Leckrone, the senior project scientist for the Hubble, said NASA's new strategy for the post-space-shuttle era does not include servicing scientific instruments in space, and he fears that vast amounts of accumulated knowledge and technical expertise will quickly vanish.
"It just makes me want to cry to think that this is the end of it," Leckrone said at a news conference earlier this week. "There is no person out there, there is no leadership out there, there is no vision out there to pick up the baton that we're about to hand off and carry it forward."
His words, streamed around the planet via the NASA Web site, ruffled the agency and incited rebuttals from headquarters. But Leckrone, who plans to retire in October, is not backing down, and yesterday he reiterated his case.
"I feel like NASA's doing what it's done before -- it comes up with a great capability and, for political or budgetary reasons or whatever, it abandons it," Leckrone told The Washington Post. He added: "I've been besieged by NASA people thanking me for saying what they think needed to be said."
NASA released a statement saying Leckrone's comments reflect a faulty assumption about the design of the next generation of spacecraft. "There is nothing about the architecture that would preclude satellite rescue work," said NASA spokesman Grey Hautaluoma.
The dispute has created a rift between Leckrone and the head of space science at NASA, Edward Weiler. The two scientists have devoted much of their long NASA careers to the Hubble -- they hugged after the successful shuttle launch last week in Florida -- but Weiler, from his perch at agency headquarters, has a dim view of sending astronauts to fix things in space.
"Servicing was great on Hubble, but it cost a few bucks," Weiler said. "The Hubble program has cost about $10 billion."
He said the agency is conducting a $20 million study to see how orbital servicing might be included in future missions. But he noted that none of the many instruments currently in orbit, other than the Hubble, were designed to be serviced.
"What are you going to service? There's nothing up there that's serviceable," Weiler said.
Leckrone responded that the shuttle and the Hubble were designed with each other in mind. That could be the template for the next generation of spacecraft and orbiting instruments, he said. For example, the next big optical telescope, which might be launched in the early 2020s, should be designed with servicing in mind.
This policy dispute reflects deeper questions over what, exactly, is the purpose of human spaceflight. NASA is in the midst of a difficult and awkward transition as it retires the shuttle and changes its sights. The Constellation initiative promises to send astronauts to the international space station in low Earth orbit, but the real target is the moon -- and perhaps Mars at some point down the road. NASA's new strategy doesn't envision playing Mr. Goodwrench with fancy telescopes, even one as beloved as Hubble.
Among those sharing Leckrone's unhappiness about that strategy is Frank Cepollina, deputy associate director for the Hubble Space Telescope Development Project at NASA's Goddard Space Flight Center. Cepollina, whose bio calls him "the father of on-orbit servicing," would like to see still another servicing mission to Hubble. He says he thinks it is wrong to launch expensive scientific instruments that cannot be fixed if they have a glitch.
"God, it's a mistake. It's a terrible mistake. It's a mistake to the taxpayer," Cepollina said. The NASA officials rushing to complete Constellation, he said, "can't be bothered or distracted with anything other than getting to the moon and back."
Constellation's "architecture" resembles that of Apollo, with a capsule called Orion perched on top of a rocket. That will remove much of the hazard associated with launching the shuttles, nestled as they are next to powerful solid rocket boosters.
But Orion is much smaller than the shuttle. It lacks a robotic arm like the one used by the shuttle in its Hubble repair job. Orion will have nothing comparable to the shuttle's payload bay. And although Orion astronauts will be able to conduct a spacewalk, that is more of an emergency capability, one requiring depressurization of the entire spaceship.
"If we develop a new vehicle, damn it, that vehicle should have all the capabilities that [the shuttle] has," Cepollina said.
Former NASA administrator Michael Griffin, responding by e-mail to Leckrone's comments, said Orion will be capable of servicing missions. And he pointed out that the Hubble's successor, the James Webb Space Telescope -- scheduled for launch in 2014 and destined for an orbit a million miles from Earth -- will have a docking ring in case it needs to be fixed robotically, or even by astronauts.
If the money spent on the recent Hubble mission were spent on an Orion servicing mission, Griffin said, it could fix a telescope.
"It is all just budget," Griffin said.