The company unveiled the design of SpaceShipTwo and WhiteKnight-Two, the two craft to be used for the space flights, at a recent New York ceremony. The former craft will release the latter at 50,000ft, with maximum planned sub-orbital space flight at 360,000ft. The journeys will last about two-and-a-half hours from beginning to end.

"The construction of the WhiteKnightTwo mothership, or carrier aircraft, is now very close to completion at Scaled Composites in Mojave, California, and is expected to begin flight testing in the summer of 2008," Virgin Galactic revealed in a press statement.

"It is the world’s largest, all carbon composite aircraft; it has a unique high altitude lift capacity, capable of launching SpaceShipTwo and its eight astronauts into sub-orbital space flight."