Nasa are infamous for their dedication to expansion, with the constant introduction of new technology to get astronauts to space. The Obama administration is on the search for a company to run a shuttle taxi service to the International Space Station. "Launching American astronauts to the space station from US soil has also been a top priority of the Obama Administration, and we're making great strides toward certifying private companies to transport our astronauts into orbit," the White House said. This new venture will mark the 39th shuttle to the space station since its launch back in 2001. The USA retired from operating with their shuttle service in 2011, passing the power and responsibility to the Russians who have been ferrying astronauts up to the station on their behalf. Although taking a huge pressure from Nasa USA the fee they charge is pretty steep, charging around $60 million for each seat used on their shuttle. "With the first commercial crew flight scheduled for 2017, some had questioned the value of a commercial crew investment that would have lasted only three years. "Extending ISS to 2024, with a concomitant increased number of flights, will drive down the per-flight cost and make this investment even more attractive." Nasa is in talks with four companies over the crew contract: Boeing, Sierra Nevada, Blue Origin – run by Jeff Bezos of Amazon – and SpaceX. The companies have until May to complete the initial designs for the taxis, which must be capable of reaching an altitude of 230 miles and remaining in orbit for three days. "Nasa is looking for a contract with a company like SpaceX,'' explained Jonathan McDowell, a scientist at the Harvard-Smithsonian Center for Astrophysics. "Before Nasa can sign the contract, companies have to test the emergency abort system because you need something which can step in if the launch rocket goes bad and avoid the danger of killing the astronauts." So, would you take a ride in the new American space taxi?