An Atlas V rocket blasted off from Cape Canaveral yesterday carrying a mysterious and controversial military 'space plane'.
Boeing's X37-B is 196 feet long, robotic, and designed for long stays in space - it orbited for 469 days on its last mission, more than a year.
What is unclear is what is aboard the unmanned craft - or what it does in orbit.
News outlets and analysts speculated that the craft could have been built to spy on Chinese satellites.
Brian Weeden of the Secure World Foundation says that the vehicle is highly controversial in China, where the government views it as a 'space weapon'.
Reports from Chinese news agencies suggested that the Chinese were devloping their own rocket-powered space plane. In 2007, the Chinese tested an anti-satellite missile against one of its own weather satellites, destroying it in orbit.
No nation has ever used military force against another in space.
In Obama's first campaign for presidency, his campaign stated, "Obama opposes the stationing of weapons in space and the development of anti-satellite weapons."
The US Army provides few details of what the craft does.
"The focus of the program remains on testing vehicle capabilities and proving the utility and cost-effectiveness of a reusable spacecraft," Air Force spokeswoman Tracy Bunko
The plane resembles a mini space shuttle and is built to ‘fly’ back from space under its own power.
On its last mission, X37-B circled Earth at 17,000 miles per hour for 469 days before landing autonomously.
At launch and landing, the space plane was pictured with staff in biohazard suits, leading to speculation that there were radioactive components on board.
Manufacturer Boeing is typically tight lipped about the plane, saying that it operates in low-earth orbit, between 110 and 500 miles above earth.
The International Space Station orbits at about 220 miles.