Tuesday, October 23, 2007

Space Jumping

Forget about bungee jumping and hang gliding. The next adrenaline pumping daredevil stunt will be hurtling back to Earth by "space diving," if entrepreneurs and extreme sports enthusiasts have their way.

They are preparing skydives from the edge of space to beat a record set by Captain Joe Kittinger of the US Air Force in 1960, who jumped from an altitude of 20 miles, reaching a speed of around 700 miles per hour in his 13 minute descent to the ground.

They aim to start with a jump from 22 miles to break Kittinger's record, then build up to 57 miles, which would be the first true space jump. If everything works as planned, paying customers might be able to start their fiery descent from space as early as 2009.

Instead of jumping from the gondola of a helium balloon, as Kittinger did, New Scientist reports today that they will be bailing out from the nose-cone of a rocket ship, one of half dozen or so being developed to loft paying passengers into the heavens for a few minutes of weightlessness and a spectacular view of the Earth.

Armadillo Aerospace of Mesquite, Texas, has been developing a computer controlled vertical take-off, vertical-landing spacecraft for the tourist trade, and the Space Diver team thinks the craft could offer the perfect jumping-off point.

The diver would trigger an airbag, springloaded seat, or a small parachute to move away from the spacecraft as fast as possible, so as to avoid a collision as he tumbled into the abyss. Then it would be up to the spacesuit to make sure the he copes with frigid temperatures and near vacuum to return safely.

At an altitude of 20 miles, the air is so thin that there will be no rushing of air and little impression of falling. Gradually, as the air becomes denser, pressure against the diver's body will increase and air friction will heat the suit, which will contain a circulating liquid cooling system.

One problem under study is how to prevent divers from going into a spin, which could leave them unconscious. The team is still debating whether a head-first posture or the traditional spreadeagled horizontal position is likely to work best. Once within a mile or so of the ground, the main parachute will deploy automatically.

The craft will be commanded from the ground, so after the diver has ejected it will return to Earth automatically. By early next year, Space Diver aims to begin low-altitude tests with dummies, then people, starting at a modest altitude of about two miles. "We need to show that we can leave the vehicle safely," Tumlinson tells New Scientist.

Ultimately, Tumlinson aims to develop technology to allow astronauts to bail out of orbiting craft and return safely to Earth, for instance in small inflatable "lifeboats".

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