Ever since the first moon mission of the 1960s, America has been prominent in outer space. But that era will draw to a close when shuttle Atlantis takes off for the last time. Liftoff is scheduled for Friday.
CBS News Aviation Correspondent Bob Orr reported from the Kennedy Space Center in Cape Canaveral, Fla., that it will be the grand finale of a 30-year space odyssey.
When Atlantis comes home, the shuttle program will be shut down.
So what's next for NASA?
Atlantis will ferry 8,200 pounds of supplies and equipment to the space station to keep it going through 2012.
Then, for the first time in 50 years, the U.S. will have no launch vehicle. And until a new one can be built -- perhaps in five years -- American astronauts will hitch rides from former space rival Russia, on Soyouz spacecraft.
Mike Griffin, a former NASA administrator, told CBS News, "Right now, we are dependent upon Russia, and I do find that unseemly for the United States. I find that unseemly in the extreme."
The Obama administration, Orr reported, insists the U.S. space program will go on with astronauts using commercially-built rockets to reach the space station, and ultimately, a new NASA-built spacecraft to go farther into deep space.
So the launch of Atlantis will be exciting, but bittersweet, Orr added, saying it will be a celebration marked by big questions about what comes next.
On "The Early Show" Thursday, NASA Administrator Charles Bolden Jr. told co-anchor Erica Hill criticism over the ending of the space program -- particularly without a back-up plan -- is misguided, saying NASA has spent seven years working on a "well-organized transition plan" for phasing out the shuttle and "moving on to the next era."
"We're excited about what President Obama is allowing us to do, working hard with the commercial entities," he said. "We hope to fly our first commercial cargo missions early next year. They will be American-made rockets flying cargo to the International Space Station, and we're already starting to work with commercial entities. (We) hope to release a request for proposal on commercial contracts to take crews to orbit; maybe three years after we let the contract, we'll have a capability."
Hill said, "A number of astronauts have spoken over the last few weeks (and) have said it seems like U.S.-manned space flight is really hanging by a thread. ... Mike Griffin said ... it doesn't seem like good national policy. And there's a lot of folks who say the next astronaut who goes up may not have a NASA badge on. Is it still an American space program if it's working out that way?"
Bolden responded, "With all due respect to (Griffin), American astronauts will continue to operate on the International Space Station at least through 2020, and we're actually certifying the station so we can operate beyond that, if that's what the nation and our international partners choose."
As for NASA after Atlantis lands, Bolden said the Kennedy Space Center will begin renovations of launch pads and facilities in preparation for commercial entities.
"We're talking to some of them about processing their vehicles here, about doing some tests here, so the future is actually bright," he said. "We're in a lull now, but we'll come back."It turns out the last launch could be delayed. While Atlantis is ready to go on launch pad 39A, the weather is dicey. NASA says the chance of a Friday morning liftoff is no better than 30 percent.
Shuttle weather officer Kathy Winters said, "We still do have a lot moisture in the atmosphere for the next few days, so it's certainly not 'clean and green.'"
Whenever Atlantis blasts off, it will be the 135th and final shuttle mission for a program that began in 1981. There have been stunning successes: The Hubble Space Telescope was carried into orbit by Shuttle Discovery, and over the last 12 years, 36 shuttle missions have built and supplied the International Space Station.
But the program has also been marked by twin tragedies that killed 14 astronauts -- Challenger in 1986 and Columbia in 2003. Orr noted they're dual reminders that exploration is never free.
Steve Wallace, a member of the Columbia Accident Investigation Board, said, "In the history of this program, we've lost going up and one coming down, and it is a tremendously risky endeavor."
While the Columbia accident did not immediately end the space program, Orr noted, it exposed significant risks. In 2004, the Bush administration ordered the eventual retirement of the aging shuttle fleet.
Looking at this mission, Bolden told Hill on "The Early Show" he hopes it will not be different from any other.
He said. "My post will be in the Launch Control Center, where I
usually am for launches. I'll be watching data like everybody else. I've
asked the team to stay focused, and if I'm going to be their leader I
need to remain focused. ... It's going to be just like every other
mission for me - hopefully. "