(AP) – NASA is facing a critical deadline to make its biggest decision in a generation: whether to go forward with plans to retire the space shuttle fleet and replace it with a new mode of space travel. But the agency still has no chief to make the $230 billion call. NASA seems so far off the White House radar, said one presidential expert, that it might as well be on Pluto. “As each day goes by, the need for these decisions becomes greater and greater, and the absence of an administrator becomes more and more an issue,” said John Logsdon, a member of the NASA Advisory Council who also advised President Barack Obama’s campaign.

Obama’s science adviser has said that crucial decisions on the shuttle and a new spacecraft to carry astronauts back to the moon will not be made until NASA gets a new administrator. In an interview two weeks ago, John Holdren did not know when that would be. A key deadline is April 30, when a congressional rule governing the shuttle’s infrastructure expires. After that date, NASA will be free to start taking apart the shuttle program if it chooses. But some in Congress want the shuttle to fly longer because retiring the fleet would force the U.S. to rely on Russia for trips to space for nearly five years. Obama has said he wants at least one more shuttle flight beyond those already planned. And that’s not all. A Congressional Budget Office report concluded that NASA cannot carry out its current plans on its existing budget. The report outlined options that include delaying the flight of the new spacecraft, spending more money to meet the current schedule or drastically cutting back on science.

NASA also has an extra $1 billion in stimulus money, but little direction in how to spend it. In past new administrations, the lack of a permanent boss might not have been such a big concern. The space program has typically focused on shuttle flights needed to complete construction of the international space station. But NASA today is in the early stages of a once-in-a-generation transition that will affect how Americans get into space and where they go. No other federal agency has faced such a large financial decision without a permanent chief. A report last month by the Government Accountability Office, the auditing arm of Congress, said the program that would replace the shuttle, return humans to the moon and perhaps send them to Mars is expected to cost more than $230 billion.

So far, the Obama administration has nominated nearly 200 officials, including an undersecretary of agriculture for rural development, an assistant labor secretary for veterans employment and training, and actor Kal Penn as a White House liaison. But at NASA, Obama has not nominated a single manager who requires Senate confirmation. “I think that tells you something,” said New York University public policy professor Paul Light, an expert in presidential appointments. “The lack of announced appointees is a sign of its priority within the administration.” And how low is NASA? “NASA has got Pluto status right now,” Light said. “As you know Pluto is no longer considered a planet.”

It’s tough to find a good NASA administrator even in the best of times because NASA is the government’s third-largest source of contracts to industry. That makes finding someone without a conflict of interest difficult, Light said, and right now the economy is a higher priority. “Some major decisions have to be made,” said Jack Burns, another member of the NASA Advisory Council and a planetary science professor at the University of Colorado. “And there isn’t too much time.” Burns said that in February.

NASA could continue down the path set by President George W. Bush and retire the shuttle by Oct. 1, 2010, choosing instead to pour money into new space vehicles that would be ready sometime in 2015. If the White House does not order changes, NASA would probably begin dismantling parts of the shuttle program on May 1, according to George Washington University space policy director Scott Pace, a former NASA official in the Bush administration. The space agency declined to say whether it would do so, but it did say that retiring the shuttle “is a matter of national policy.”

In his brief budget request in February, Obama said he would fly the shuttle through 2010 and continue with plans to go to the moon. He did not get into specifics about the somewhat controversial design of new moon-mission spacecraft. The space agency could scrap or delay the shuttle retirement plans and change or dump the new spaceship system. “My expectation is that NASA will be given marching orders and that they won’t be the same as that of the Bush administration,” said Rice University physicist Neal Lane, White House science adviser to President Bill Clinton. “They are still working on the old plan, and the clock is ticking.”

So what will NASA do? NASA referred questions to the White House, but acting Administrator Chris Scolese did say in a statement: “All NASA missions and programs are proceeding uninterrupted.” The White House would not answer specific questions about the space agency’s future. “The White House is fully engaged with NASA,” White House spokesman Nick Shapiro said in an e-mail. “As with all government agencies, it is important that NASA’s programs are properly matched to available resources.”

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