Freefalling at the speed of sound

Austrian base jumper Felix Baumgartner will attempt to become the first person to break the speed of sound in freefall this year, and in doing so smash a nearly 50-year old record. In a project called 'Red Bull Stratos' he will undertake a balloon flight up to 120,000 feet and then leap out in a bid to be the first human being to fall at supersonic speeds, before parachuting down to earth.

The current record is held by US Air Force Colonel Joseph Kittinger who in August 1960 stepped out of a balloon at the height of 102,800 feet (19 miles) over the New Mexico Desert, and fell for four and half minutes of speeds up to 614 miles per hour. He set records for the fastest freefall, longest freefall, the highest parachute jump and the highest manned balloon flight. Inscribed in the door of his gondola were the words "This is the biggest step in world." Kittinger then went on to serve in Vietnam where he was shot down an spent 11 months as a prisoner of war in the notorious 'Hanoi Hilton' prison.

Baumgartner will be trying to break three of the 50-year old records, aiming to fall at a speed of 700 miles per hour. A detailed analysis of the 'space dive' can be found in the recent issue of New Scientist.