This story was updated at 5:41 p.m. ET.
President Obama's plan for America's space program, according to early reports, represents a fundamental shift for human spaceflight, some experts say.
The reports suggest the Obama administration intends to move toward relying on commercially-built spacecraft, rather than NASA's own vehicles, to carry humans to low-Earth orbit. The plan would also involve extending the International Space Station's lifetime and abandoning current plans to send astronauts on moon missions by 2020.
"This is definitely a paradigm shift in the way the country will go about its space program," said John Logsdon, a space policy expert and professor emeritus at George Washington University in Washington, D.C.
A spokesperson for NASA's Constellation program overseeing the moon mission work at the Johnson Space Center in Houston told SPACE.com that it would be premature to make any comments on the agency's future until after NASA's spending goals are announced next Monday in Washington, D.C.
Boost to the private sector
The new reliance on the commercial spaceflight industry to take over the duty of ferrying humans back and forth from the space station is particularly significant, experts say.
On Wednesday, a senior White House official told two Florida newspapers (Florida Today and the Orlando Sentinel) that the administration would ask for an additional $6 billion over the next five years to help private companies develop this capability. So far, no commercial company has ever independently launched humans into orbit in its own spacecraft.
"The $6 billion shows that they are very serious about making it a successful and safe program," said Brett Alexander, president of the Commercial Spaceflight Federation, a private industry group. "I think what they're putting in place is bold and exciting. Bringing commercial and private [companies] into it will reinvigorate human spaceflight."
Alexander said he's confident that industry can rise to the challenge and meet this new task, and others agree.
"I think the commercial outfits ought to be given a chance to succeed," said Leroy Chiao, former NASA astronaut and member of a blue-ribbon panel President Obama put together last year to review NASA's plans. "The technology to get into low-Earth orbit has been around for almost 50 years ? it's nothing particularly new."
In fact, the Obama administration's plan is seen by some as following closely one of the possible paths put forward by the panel, which was headed by Norman Augustine, a retired Lockheed Martin chief executive.
The committee found that NASA was severely underfunded to accomplish its vision of replacing its space shuttle fleet with new Orion vehicles and Ares rockets. It also suggested that relying on commercially built spacecraft would allow NASA to focus on more ambitious human spaceflight missions, like expeditions to a nearby asteroid or the moons of Mars.
Not everyone agrees with the new plan, though. Former NASA administrator Michael Griffin, now an eminent scholar at the University of Alabama, Huntsville, sharply criticized the decision, questioning whether a commercial vehicle will be ready to carry humans to the station anytime soon.
"Today we have in orbit a $75 billion International Space Station, a product of the treasure and effort of 15 nations, and the president is recommending that we hold its future utility and, indeed, its very existence hostage to fortune, hostage to the hope that presently nonexistent commercial spaceflight capability can be brought into being in a timely way, following the retirement of the Space Shuttle," Griffin said in a statement.
And others are unhappy that the Obama space plan would potentially cause the loss of many NASA jobs if the business of launching humans into space is handed over to the private sector after the space shuttles retire.
"For Florida it would be devastating in the short term," Roger Handberg, a political scientist at the University of Central Florida who has written extensively on space policy. "If NASA goes into relative decline or suspension of manned launches, we're going to be in a hole.
Florida senator Bill Nelson (D-Orlando) has also come out against the plan, and other politicians from states that would lose jobs are also likely to fight the proposal. President Obama intends to officially announce his plans for space when he submits his federal 2011 budget request Monday, which will include his request for NASA funding.
Some say to wait until then to judge the plan.
"Most of what we're reading in the media right now are rumors and I think we really would do a disservice to ourselves if we jumped to conclusions," Chiao said.
What about the moon?
One of the major questions about the new plan is what will happen to the goal of returning people to the moon. Opinion is split on whether or not Obama plans to completely scrap the Constellation program, which is NASA's current vision for space exploration. Under the program, work has already begun to design a new rocket, Ares I, and crew capsule, Orion, to carry astronauts to the moon and beyond. The first test launch of that booster went off successfully in October 2009.
"I think it would be premature to say that Constellation is going to end," Chiao told SPACE.com. "What I think would be more probable is that there would be some variation on current plans."
But others take a dimmer view.
"Constellation is dead," Logsdon said. Yet he emphasized that that doesn't mean America won't go back to the moon. It just won't go back on the schedule and vision laid out by President Bush in 2004.
"The 'vision' to return to the moon that has been guiding NASA since 2004 was always an inadequately funded fantasy," said Joan Johnson-Freese, chair of the Department of National Security Studies at the Naval War College in Newport, R. I. "One of the goals of the Obama space plan appears to be to give NASA the opportunity to build and use enduring hardware ? rather than an impulsive and unrealistic return-to-the-moon on a shoestring plan."
While the shift in policy may take some adjusting to, some are hopeful that it will allow America to retain its leadership as a space-faring nation.
"Any large organization doesn't necessarily like change so it's not surprising that people are concerned and worried," Chiao said.
"But change always brings opportunity. I'm cautiously optimistic."
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