UPDATE: 1:45 p.m. ET — Baumgartner’s historic jump was scheduled for today, but has since been delayed due to high winds.  Australian daredevil Felix Baumgartner is set to step out of his fiberglass space capsule, 120,000 feet above the Earth, and jump.  But the biggest threat to Baumgartner is not his speed nor the hard crust of Earth — it’s space itself. At altitudes upwards of 63,000 feet, gas bubbles begin to form in the body’s fluids — a phenomenon known as ebullism — which can result in unconsciousness or even death.From there, he’ll fall for about five and a half minutes of free falling, at which point he’ll deploy his parachute and float down another 5,000 feet to the desert near Roswell, New Mexico (appropriately).  His speed during this leap from space? Perhaps as great as 720 miles per hour (Mach 1.1), which would make him the first skydiver to break the sound barrier.  What’s protecting Baumgartner from space then? His space suit, a specially designed piece of technology that should keep the pressure around his body something like what a human would experience at 35,000 feet. As Andrew Zaleski wrote in the July/August issue of The Atlantic:  Baumgartner’s suit, which was designed by space-suit specialists at David Clark Company, has four layers: an innermost comfort liner; a bladder, or gas container, fitted to his body; netting to keep the bladder in place; and an insulating exterior. … Baumgartner’s full-pressure suit maintains an internal pressure equivalent to that found at 35,000 feet.  The new suit has much in common with the full-pressure suits the shuttle astronauts wore, but it’s different in one critical and potentially life-saving regard: maneuverability. NASA space suits, which were intended to keep astronauts alive if the shuttle cabin lost pressure while entering or exiting orbit, were designed for sitting. They are extremely hard to move around in when fully pressurized. Jonathan Clark–the Stratos project’s medical director, a former NASA flight surgeon, and the widower of Laurel Clark, one of the astronauts who perished in the Columbia accident in 2003–told me that attempting to maneuver through a bailout hatch in such a suit would be nearly unthinkable.  And this is where Baumgartner’s suit represents such a leap forward. If he’s to have a decent shot at surviving the fall, his suit must be maneuverable. He needs to go from a pencil dive, when he first hops off his capsule’s platform, into a head-down “delta” position, with his arms at his side. If he flubs that hop–if he pushes off with too much force, say–he could tumble into an uncontrolled spin, the force of which could kill him. And so his getup, unlike NASA space suits, which come in 12 standard sizes, is custom-tailored.  As he dives down to Earth, he’ll be in radio communication with only one person: Joe Kittinger, now 84, who in 1960 set the current records for free falls, jumping 19 miles from a balloon. The suit Kittinger wore was only partial pressure. “Comparing my equipment to what Felix has is like comparing a Model T to a 2020 Ferrari,” he told Zaleski.  This article originally published at The Atlantic here.  The Atlantic is a Mashable publishing partner that is a multimedia forum on the most-critical issues of our times, from politics, business, urban affairs, and the economy, to technology, arts, and culture. This article is reprinted with the publisher's permission.
If the Australian skydiver is to survive his plunge, it'll be thanks in part to his specialized, pressurized protection.