President Barack Obama is expected to deliver his budget request for fiscal year 2011 on February 1, but to hear many commentators tell it, the sky has already fallen on NASA.

On Wednesday the Orlando Sentinel reported that Obama's budget would essentially scrap the Constellation program, NASA's current plan to develop a successor to the space shuttle. The shuttle, which has just five remaining scheduled launches, will be retired this year or in 2011, and without Constellation on the horizon, the future of U.S. manned spaceflight is unclear but would likely require commercial providers to boost astronauts into orbit.

In a statement Thursday, former NASA administrator and die-hard Constellation champion Michael Griffin said that the rumored changes, if true, indicate that Obama "has chosen to recommend that the nation abandon its leadership on the space frontier," a decision that Griffin called "even worse" than President Nixon's termination of the Apollo program. Carolyn Porco, who leads the imaging team for the Cassini spacecraft, lamented the news on Twitter: "Looks like we're gonna pull out of the race."

Before the budget request becomes official, it's impossible to say with certainty what it contains. It's also impossible to project how Congress will act on that budget request. But it's worth considering: if things play out as it's feared they will, what are we really losing, and what was lost a long time ago?

Constellation is a Bush-era plan stemming from his 2004 Vision for Space Exploration, which was prepared in the wake of the Columbia accident. The original program: retire the shuttle by 2010, develop a new crew-launch rocket (later named Ares 1) for use no later than 2014, and return humans to the moon between 2015 and 2020.

In 2009, five years after Bush's announcement, the Obama administration convened an independent committee chaired by former aerospace executive Norman Augustine to take Constellation's pulse. What the panel found was an ever-widening chasm between stated goals and fiscal feasibility. The group concluded that the only aforementioned target reasonably within sight was phasing out the space shuttle—and even that would likely slide to 2011.

Within NASA's current budget, Augustine's panel estimated, returning to the moon with Constellation would be impossible until the 2030s at best—and even that would require dumping the International Space Station (ISS) into the ocean in 2016, just five years after its long-awaited completion. A brighter future for Constellation could be had if NASA de-orbited the ISS and got a significant budget boost from Congress. In that scenario, the Ares 1 crew launcher of the Constellation program could conceivably be ready in 2017, and U.S. astronauts could be back on the moon in the mid-2020s.

But what's the rush to get back to the moon, anyhow? The U.S. won that race and won it decisively—whatever nation reaches the moon next, whether Russia, China or some other contender, it likely won't do so within 50 years of Apollo 11. Many have argued that Constellation's moon deadline was a misguided goal from the start and that a more forward-thinking blueprint for space exploration would involve unprecedented feats, such as a manned mission to a near-Earth asteroid. Obama is said to favor this "flexible path" to space exploration.

Augustine's group laid out several possible paths NASA could take with its manned spaceflight program, some within the agency's current budget and some with a bit larger outlay. Only the two unsavory choices mentioned above spared Constellation's crew launcher, Ares 1. Every option that would accommodate the ISS required leaning on commercial entities to lift astronauts into orbit—the approach that Obama is rumored to favor. So why should that choice be so controversial now, when it has appeared almost inevitable since September, when the Augustine commission released its preliminary findings? (It seemed highly unlikely that Obama would ditch the ISS, which has cost a fortune and appears to have strengthened crucial ties with other nations' space agencies.)

NASA has relied on the private sector to launch satellites for years; even manned shuttle missions have had significant commercial involvement. I couldn't help but notice, in a Thursday preview screening of footage from the forthcoming documentary Hubble 3D, that the personnel suiting up the astronauts before the May 2009 STS-125 mission were wearing jumpsuits emblazoned with the United Space Alliance logo, not the familiar NASA blue meatball. (United Space Alliance is a corporation jointly owned by Boeing and Lockheed Martin.)

That's not to say that private companies are ready for the complexity and risks involved in manned launches, but Augustine's group estimates that they might be by 2016, a year ahead of Ares 1 in even the most favorable scenario. All of which underscores the point: Increased commercial involvement in human spaceflight is far from ideal on a number of levels, but what is the alternative? The rockets of the Constellation program are behind schedule, over budget, and can apparently proceed only at the expense of the International Space Station. Whatever space race still exists, the U.S. is unlikely to win it by waiting for the Ares rockets to pass muster. NASA has had years to develop a replacement for the aging space shuttle and has made little headway; perhaps it's time for someone else to give it a try.

Artist's conception of the Constellation program's proposed lunar lander: NASA