Carried by balloon to above 99 percent of the Earth's atmosphere, Stearns will wear a customized pressurized space suit. Her freefall velocity may exceed the speed of sound, heading toward Mach 1.3. Maintaining a head down position will get her through transonic, and supersonic speed regimes. But as she begins to enter heavier atmosphere, a dangerous transonic phase comes again. At this point, her skydiving skills are to be tested in order to maintain stability until parachute deployment.

The jump is tentatively set for over New Mexico, perhaps in October 2001.

First of all, high-altitude skydiving is on the cutting edge, said Mark Norman, an instructor with Freefall Adventures in Williamstown, New Jersey. "Certainly, they are challenging themselves, that's for sure. They are definitely pushing the envelope without any shadow of a doubt," he told SPACE.com.

	Images
	Air Force Captain Joseph Kittinger, Jr. jumps from Excelsior III balloon gondola in 1960 test, freefalling toward Earth for over 4 minutes.
	A concept poster for Moose.
	To use Moose, an astronaut first would climb inside a big, foam-filled plastic bag.
	Eventually a parachute would cushion the astronaut's drop to land or water on Earth.
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Norman said that high-altitude skydivers much think safety first, with regards to oxygen and pressurization issues. "So it lends itself to a lot of difficulties and a lot of impracticalities that we don't necessarily need to deal with in the commercial, mainstream skydiving industry," he said.

Building a business on people swooping down from the edge of space doesn't seem too practical at the moment, Norman said.

But Geoff Sheerin, team leader of the X Prize entry, the suborbital, passenger-carrying Canadian Arrow, believes what is taking place is an early form of spacediving.

"A rocket can take a spacediver to any altitude desired in just minutes, resulting in less time exposed to the dangers of vacuum and cold," Sheerin said. "I think this will ultimately lead to suborbital vehicles being the transport of choice for spacediving. Anyone using a rocket for spacediving can demolish any balloon record ever made," he said.

"If you look at the lower energies involved for suborbital flight, compared to orbital speeds, you realize that material and technology of today can turn spacediving from a suicide jump into a very survivable extreme sport," Sheerin said.