As the Atlantis space shuttle blasted towards Space today, NASA laid to rest its famed Space Shuttle Program and entered what some in Congressional space committees are calling a "critical period" and "uncertain era." Experts just call it "The Gap."
"With the retired Shuttle Program, America's legacy as the unrivaled world leader in space exploration enters a new and uncertain era," House Space and Aeronautics Subcommittee Chairman Steven Palazzo said in statement today. "NASA faces many new challenges to sustain America's leadership in space, especially during this difficult budgetary time."
After decades of American dominance in space exploration, the Atlantis shuttle flight brings the country into the first significant stretch of time in decades during which the U.S. will be unable, on its own, to put astronauts into space.
"I don't like it at all," Rep. C.A. Dutch Ruppersberger, a Maryland Democrat who has led oversight of the space program, said in May. "The previous administrations have not made space a priority. It's expensive. Now we're in this situation."
If the fears of some in Congress come true, a period of unprecedented drift for the space program could follow today's final Shuttle launch.
"With the retirement of the Space Shuttle, NASA will face a critical period and will need Congress's support and direction to focus its limited resources on sustaining America's leadership in space," House Science, Space and Technology Committee Chairman Rep. Ralph Hall said today.
With no American vehicle capable of carrying astronauts into space, the U.S. will be forced to pay the Russians a steadily escalating price -- eventually hitting $62.7 million per seat -- to carry Americans and international partners to the International Space Station through 2016.
The public posture of NASA officials has been to focus on a modernized program that relies far more on private companies to handle the increasingly routine work of hoisting satellites and servicing the space station, while dedicating U.S. government resources to planning the more complex task of taking astronauts deeper into space.
But a June report from the Office of the Inspector General found that "NASA faces multiple challenges and risks as it expands its Commercial Crew Transportation program."
The report detailed a litany of challenges that come with relying on commercial companies to carry crews of astronauts into space.
"The commercial human spaceflight industry is in its infancy," the NASA inspector general found. "Many of the risks associated with achieving anticipated cost savings are largely out of NASA's control."
Also, privately, political leaders are bemoaning what could be a deeply unsettling period during which the U.S. will have no way to put humans into space -- and efforts to reach more distant destinations appear hazy and uncertain. Some told ABC News they are worried that without a clear destination or proven spacecraft to get there, it could be a long, long time before a manned U.S. rocket heads for the heavens.
"What used to be a gap is now a cliff," former NASA administrator Michael D. Griffin said in May. "What really is happening here is the destruction of an American institution that has been preeminent in the world for the past 40 years. I believe it's tragic."