This image of space shuttle Atlantis was taken shortly after the rotating service structure was rolled back at Launch Pad 39A, Thursday, July 7, 2011. Atlantis is set to liftoff today, Friday, July 8, on the final flight of the Space Shuttle Program. NASA

Earlier this week, shuttle from NASA's space shuttle program lifted off into space for the final time.

Atlantis became the final shuttle to launch into space as part of a program which began in 1981. The shuttle is currently in the midst of a 12-day mission. Once it returns from space, the shuttle era will be over.

The next time a shuttle launches from U.S. soil with astronauts on it? No one knows exactly but NASA does have some plans to make sure U.S. manned space missions don't become a thing of the past.

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 failure is not an option, Charles Bodden, NASA's Administrator, said in a recent speech.

The space agency is working on designing and building new space modules, which will send astronauts to asteroids, back to the moon and even on Mars. NASA has a goal of sending a man to Mars by the 2030s.

We will soon announce the design for the heavy-lift Space Launch System that will carry us out of low Earth orbit. We are developing the technologies we will need for human exploration of the solar system, including solar electric propulsion, refueling depots in orbit, radiation protection and high-reliability life support systems, the space agency said recently on its website.

For the next generation of manned space travel, NASA is working with the private sector. The agency has awarded contracts to companies like Lockheed Martin to built new age space crafts. Other companies like Blue Origin, Sierra Nevada Corporation, Space Exploration Technologies (SpaceX) and The Boeing Company were awarded NASA contracts for this project.

With NASA's support, SpaceX will be ready to fly its first manned mission in 2014, SpaceX CEO and Chief Designer Elon Musk said recently.

SpaceX is working on a spacecraft it has called the Dragon. The company says it can carry seven astronauts at a time to the space station at a cost of $20 million a seat. Spacex's Falcon 9 became the first non Shuttle rocket to be man-rated for space exploration in 2010.

Until this private/public partnership launches, NASA will rely solely on the Russian Soyuz to ferry astronauts to and from the International Space Station (ISS). This will cost $753 million a year - about $63 million per seat.

There are also other private companies looking to get into space all on their own without help from NASA. Billionaire mogul Richard Branson is one of the men leading this charge with his company Virgin Galactic. The company has already sent rockets to the moon and is looking to help create a space tourism industry. In a previous interview with CBS News, Branson said he was inspired by the moon landing.

It was one of those momentous moments in your life. I was absolutely sure I would go to the moon sure thereafter and the years ran by, it seemed clear NASA hadn't really got a big interest in sending you or me or Joe Public up into space, and so I was determined to do something about it, Branson said.

Follow Gabriel Perna on Twitter at @GabrielSPerna

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