Virgin Galactic is to unveil its commercial spacecraft, SpaceShipTwo, today.
The craft will be the first commercial spaceship ever to be built. Around 300 wealthy wannabe astronauts have already paid a deposit for a $200,000 trip. The company is aiming for a fleet of five.
The design is based on the previous prototype, SpaceShipOne, which won a $10 million prize in 2004 by becoming the first privately operated manned craft to reach space. But it's twice the size, at 60 feet long, and can carry six passengers and two pilots. The rocket engine burns a combination of nitrous oxide and a rubber-based solid fuel.
Virgin Galactic has been testing the mothership, White Knight Two, for the last year. Test flights of SpaceShipTwo are expected to start next year.
Commercial flights will take place out of a spaceport in New Mexico. Flights will last about two and a half hours, including just five minutes or so of weightlessness.
SpaceShipTwo will piggy-back on the mothership and be released at 50,000 feet, from where it will climb to about 65 miles - high enough to clearly see the curve of the Earth. It will then return to the atmosphere and glide to a landing like a plane.