This
story was updated at 7:52 a.m. EDT.
As NASA's
50th anniversary approaches, the agency finds itself at a crossroads between
the waning era of the U.S. space shuttle and serious hurdles ahead to build a
replacement spaceship while still keeping American astronauts flying.
The U.S. space
agency turns 50 years old on Oct. 1 with the last flight of its three aging
shuttles already set for May 31, 2010 aboard the orbiter Atlantis.
NASA
officials in charge of the developing the shuttle's replacement - the Orion
Crew Exploration Vehicles and their Ares I boosters - hope to have the
spaceship ready for manned flights by 2014, though unless Congress steps in
soon American astronauts will likely be grounded beginning in 2012 due to
restrictions on NASA's ability to buy seats aboard Russian spacecraft.
Meanwhile, the agency is simultaneously taking an academic look at what's
needed to extend shuttle missions through 2015 to be ready for any questions from
the new administration after November's presidential election.
"It's kind
of a unique juncture of history that we are engaged in at this point in time
with so many issues, and the tasks are pretty large and quite daunting," said
Roger Launius,
a former NASA historian and senior curator with the Division of Space History at the
Smithsonian Institution's National Air and Space Museum in Washington, D.C.
"It's time to move on."
Shuttle
to Orion
NASA's has
planned to retire its three shuttle fleet since 2004 under the Vision for Space
Exploration, which includes bringing Orion and Ares I online by 2015 and
sending astronauts back to the moon by 2020. The plan calls for Ares I rockets
to launch Orion capsules to orbit on flights to the International Space Station
or to link up with a lunar transfer stage and Altair moon lander lofted
separately atop a planned Ares V heavy-lift booster.
Budget
shortfalls and recent shuttle flight delays prompted NASA's Constellation
program to push back internal targets for test flying Ares and Orion crew
vehicles, though officials hit a milestone earlier this month when an
engineering panel signed off on the preliminary design for Ares I rockets.
"You're
always going to find out that there are things you don't know, which can be
fixed. So figuring out and fixing them is what we do," NASA Administrator Mike
Griffin said in a televised agency-wide update on Sept. 12. "Ares and Orion are
going very well for development projects on a scale that the agency has not
tackled for decades."
The agency
had hoped to launch the first Ares I test - dubbed Ares I-X - from the Kennedy
Space Center in Florida by April 15, 2009, under a plan to begin manned flight
tests as early as 2013. But delays to the next shuttle flight - Atlantis'
STS-125 mission to overhaul the Hubble Space Telescope - pushed the Ares
I-X test flight to no earlier than next June because NASA must hold the Ares
pad in reserve for a second shuttle, which is serving as a rescue ship in case
of an emergency.
The Hubble
flight is slated to lift off Oct. 10, after being pushed from an earlier August
launch date due to fuel tank delays.
Funding
constraints, meanwhile, have hindered design review plans for the Orion Crew
Exploration Vehicle. NASA is currently spending about $3 billion per year
through 2010 on Orion and Ares I, but could have been farther along if
additional funds were available, program managers said.
"We needed
about $1 billion for each of the next two years to really put us on the glide
path to make that a high confidence plan," said John Hanley, manager of NASA's
Constellation program overseeing Ares and Orion development, of the 2013 target
in a Sept. 10 briefing. "When that didn't materialize, we of course had to adjust
our schedule in order to allow the work to fit the money, and that's what we've
done."
New
spaceship hurdles
Challenges
in developing any new human spaceflight system are to be expected, and NASA's
Orion and Ares have their fair
share.
"I think
they're obviously making progress toward fielding a new vehicle, but they do
have enormous technical challenges," Launius said of NASA, adding that the U.S.
has not designed a manned spacecraft from scratch since the birth of the
shuttle fleet in the early 1970s. "We basically do this once a generation and
we're now at that point where we're doing it."
The current
Ares I design, a two-stage rocket that uses a five-segment version of the space
shuttle's solid rocket booster as a first stage, shakes too much. Engineers
have come up with a novel shock absorber plan to mitigate the excessive
vibration.
Design
teams have also been dogged by the Orion capsule's weight, which they have been
working to slim down for extra launch margin since the spacecraft will be used
for rides to the International Space Station and planned long duration treks to
the moon. The design review process for that component has been delayed to some
time next year.
Early work
is underway to modify the Ares I rocket's launch pad at the Kennedy Space
Center to ward off lightning and other hazards. Meanwhile, Ares I engineers are
tackling time-consuming, but not insurmountable problems like smoothing out the
rocket's stage separation and deciding to safeguard the booster to fly through
rain, hail or direct lightning strikes, said Ares project manager Steve Cook.
"We've
certainly got design challenges ahead, but if we didn't have challenges we
wouldn't need engineers," he added.
American
access to orbit
While
engineers tackle plans for Orion and Ares, NASA has already set the last
flights for each of its three remaining space shuttles - Atlantis, Discovery
and Endeavour.
Under the
current schedule, Atlantis would launch its last flight, STS-131, to the space
station on Feb. 11, 2010. Discovery and Endeavour would follow, lifting off on
April 8 and May 31 of that year, respectively.
NASA had
hoped to rely on Russian Soyuz spacecraft to launch American and partner
astronauts to the International Space Station between the shuttles' retirement
the first manned Orion flights.
But unless
Congress extends the agency's exemption from part of the Iran-North Korea-Syria
Non-proliferation Act (INKSNA) by year's end, American and NASA partner
astronauts will miss at least one of the space station crew rotation flights in
2012. Russia's recent military conflict with neighboring state Georgia in early
August has cast a pall over the waiver talks.
"I've been
putting every bit of political capital that I might have or can borrow behind
securing an extension of that wavier until we can get Ares and Orion flying,"
Griffin said last week. "But it's tough and the Hill is not of one mind on that
subject."
Some
supporters include Sen. Bill Nelson (D.-Fla.), who has been advocating a
waiver extension for astronaut seats, but has urged NASA to commit to U.S.
commercial launch services for station cargo. Others, like Rep. Dave Weldon
(R-Fla.), believe relying solely on Russia for U.S. access to space to be a
grave misstep.
"Laying off
thousands of experienced space program workers and relying on Russia to get the
U.S. into space was a bad idea then, and it is even a worse idea now," Weldon
said in a Sept. 12 statement. "By granting the Russians a waiver, as he now
advocates, we will guarantee thousands of pink slips to workers at KSC. Russia
continues to sell dangerous technologies directly related to weapons of mass
destruction to Iran, defies sovereign rights in Georgia, and threatens Poland
with intervention."
Shuttle
futures
Also
clouding the issue is the upcoming presidential election, which has prompted
NASA to take a second look at what steps would be required to extend its
space shuttle flights through 2015 in order to answer any questions from
the new administration.
Last month,
Republican presidential candidate John McCain (R-Ariz.) and other senators sent
a letter to President George W. Bush beseeching his administration from instituting
any policies that would prevent U.S. shuttles from flying beyond 2010.
Democratic presidential candidate Barack Obama (D-Ill.), too, has pledged to
continue the Constellation program and has said in the past that extra space
shuttle flights might be an option.
Griffin has
said that the odds of a loss of vehicle or crew failure during shuttle mission
will increase dramatically if the program is extended to fill the gap between
orbiter retirement and Orion operations in 2015. Adding two shuttle flights per
year would shift the odds from a 1-in-80 chance of a failure to 1-in-8 flights.
"That's the
facts. That's where we are," Griffin said this month. "I'd rather work toward
spending our money toward building a safer system."
And while
NASA has begun terminating some of its contracts that support space shuttle
missions, there is some flexibility as to what it might be able to do if
directed by the new administration. John Shannon, NASA's space shuttle program
manager, said earlier this month that while extending shuttle flights
through 2015 may not delay plans for Ares I launches, it would likely delay
Ares V rocket development that would support new manned missions to the moon.
"We have been aggressively retiring
thing that we do not need for the space shuttle program," Shannon said. "But we
haven't reached the point of no return."
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