As the final space shuttle headed toward the International Space Station, back on Earth debate was raging about what the future of the US space programme holds. NASA has faced harsh criticism from some prominent names, including first man on the moon Neil Armstrong, for the lack of a clear path moving forward, but others see a bright, if dramatically different future.
Amid tight budgetary constraints, President Barack Obama killed plans by his predecessor George W Bush to build a spacecraft to return to the moon. Instead he wants the space agency to focus on building a rocket that can take astronauts into deeper space and turn over much of the routine work of ferrying astronauts into low-Earth orbit to commercial firms.
"Today's launch may mark the final flight of the space shuttle, but it propels us into the next era of our never-ending adventure to push the very frontiers of exploration and discovery in space," Obama said in a statement after Friday's launch of the shuttle Atlantis.
"We'll drive new advances in science and technology. We'll enhance knowledge, education, innovation, and economic growth. And I have tasked the men and women of NASA with an ambitious new mission: to break new boundaries in space exploration, ultimately sending Americans to Mars. I know they are up to the challenge - and I plan to be around to see it." But critics say the new plans do not offer a clear vision and have no realistic, near-term goal.
"NASA's human spaceflight programme is in substantial disarray with no clear-cut mission in the offing," Apollo astronauts Armstrong, Jim Lovell and Eugene Cernan wrote in a USA Today editorial in May. "After a half-century of remarkable progress, a coherent plan for maintaining America's leadership in space exploration is no longer apparent." NASA officials faced questions Friday about how they will ever convince the American public of their plans, if even some of their own supporters aren't convinced.
Kennedy Space Centre director Bob Cabana thinks it's only a matter of time - once the plans for the next-generation craft are publicised there will be something for people to rally around. "I don't see it as end. I see it as a transition," said Bill Gerstenmaier, NASA's associate administrator for space operations, noting the end of the shuttle programme will allow a more clear focus on what comes next - operating the International Space Station and developing the next-generation spacecraft.
That system now known as the Multi-Purpose Crew Vehicle is based largely on the spacecraft called Orion that was part of Bush's plans to return astronauts to the moon. Up to four astronauts will be able to live for 21 days aboard the cone-shaped craft, which is designed to be 10-times safer than the soon-to-be-retired space shuttle fleet. Scott Pace of the Space Policy Institute at George Washington University however thinks that ending the Bush-era plans to return to the moon was a mistake because Obama's objective of reaching an asteroid or Mars isn't feasible in the near-term.
The move also leaves many international partners cut off from the US-led space programme with little chance that developing nations, like India can take part in the effort. "By neglecting the moon," he said. "It actually undercut areas for international co-operation, particularly with Asian countries." Others fear US leadership in space will slip, with astronauts reliant on Russia for rides to the ISS and China showing no signs of slowing down its burgeoning space programme.
"I think other countries will step in and take our place, which is sad because we were one of the leaders along with Russia, and I think it's a shame to relinquish that," said tourist Judy Clavelli as she toured the National Air and Space Museum in Washington this week. But what that leadership looks like is a matter of opinion with advocates of commercial spaceflight pointing to a renewed commitment that will spur a new American industry.
"This week, we welcome the arrival of the Commercial Space Age," John Gedmark, executive director of the Commercial Spaceflight Federation, said in a statement. "In fact, thanks to commercial spaceflight, the next decade will see more flights to space than in any previous decade of the Space Age. This marks a historic milestone."
NASA Administrator Charlie Bolden stressed that US leadership in space will not end with the shuttle. "American leadership in space will continue for at least the next half century because we've laid the foundation for success, and for us at NASA failure is not an option," he said.