As NASA preps for its final Space Shuttle mission, people are wondering whether the Atlantis lift-off is a time to celebrate or mourn. Read what NASA's Charles Bolden says about outsourcing low-orbit to the private sector.

NASA's final Space Shuttle mission countdown is underway and the handwringing over a manned flight hiatus is picking up. The big question: Does the last Shuttle mission signal weakness or a necessary transition to a better way?

The Atlantis is scheduled to lift off for a final mission on Friday, but weather may delay the launch time. The last mission is essentially a final supply run to the International Space Station. After that, NASA -- and the U.S. space program -- is in a manned flight limbo of sorts as private sector picks up the space travel baton.

A sampling of recent press coverage highlights some of the reality behind the final Shuttle mission.

An Associated Press account rounds up how NASA legends Neil Armstrong and John Glenn are leading a group of critics who say that the U.S. space program is ignoring a long-held belief that there should be a backup plan. Indeed, the end of the Shuttle program leaves a manned flight vacuum.

The Wall Street Journal notes that the International Space Station now depends solely on Russia, the historic rival to the U.S. in the space race. The U.S. and European Space Agency will depend on Russia's Soyuz for a lift. In other words, Russia has a monopoly on manned space flight. Jean-Jacques Dordain, director of the European Space Agency, is quoted as saying that the situation is "uncomfortable" and a "collective mistake."

The end of the Shuttle means the loss of jobs and specialized expertise in space, CBS News notes.

So where is NASA headed? President Obama said on his Twitter town hall that NASA needs a new frontier. NASA Administrator Charles Bolden defended NASA, its plan to move forward and shot down critics over a backup plan. Bolden said:

As a former astronaut and the current NASA Administrator, I'm here to tell you that American leadership in space will continue for at least the next half-century because we have laid the foundation for success - and for NASA failure is not an option. Once again, we have the opportunity to raise the bar, to demonstrate what human beings can do if we are challenged and inspired to reach for something just out of our grasp but not out of our sights.

In many respects, Bolden noted that the U.S. needs to outsource low-orbit to the private sector.

When I hear people say - or listen to media reports - that the final Shuttle flight marks the end of U.S. human spaceflight, I have to say . . . these folks must be living on another planet. We are not ending human space flight, we are recommitting ourselves to it and taking the necessary - and difficult - steps today to ensure America's pre-eminence in human space exploration for years to come.

But we have to do things differently. For one, we have to get out of the business of owning and operating low Earth orbit transportation systems and hand that off to the private sector, exercising sufficient oversight to ensure the safety of our astronauts.

We need to focus on deep space exploration, while empowering today's innovators and entrepreneurs to carry out the rest. This new approach to getting our crews and cargo into orbit will create good jobs and expand opportunities for the American economy.

And let me be crystal clear about this: I believe that American companies and their spacecraft should send our astronauts to the International Space Station, rather than continuing to outsource this work to foreign governments. That is what this Administration is committed to, and that is what we are going to do.

Along with supporting the ISS and commercial crew transportation, NASA will pursue two critical building blocks for our deep space exploration future - a deep space crew vehicle and an evolvable heavy-lift rocket. And we will make the technology investments required to begin the era of deep space exploration today.

In other words, the future of manned flight will depend on companies like SpaceX, Lockheed Martin and Boeing.

If the U.S. can go through the transition to private low-orbit vehicles, maintain leadership and keep focused on going to Mars and deep space perhaps this three-year hiatus is worth it. In the meantime, many folks will wonder if that Atlantis lift-off is a time to celebrate or mourn. Related:

This post originally appeared on SmartPlanet, a sister site of TechRepublic.