While Felix Baumgartner and his team in Roswell, N.M., have had a couple of disappointments and weather-related cancellations this week, the Austrian daredevil will attempt the supersonic leap from the edge of space again today.
When the 43-year-old skydiver and Base jumper takes the leap from 23 miles in the air, he will break the world record for the highest skydive. He will accelerate from zero to 690 miles per hour in 35 seconds, and become supersonic for almost a minute of the roughly 10-minute leap.
"I practiced this for so many years," Baumgartner said. "This is my biggest dream."
Baumgartner was set to take the leap Tuesday, Oct. 9, but winds at 20 miles per hour at the top of the 55-story helium balloon that was to lift him into the stratosphere were far faster than the safe 3 mph limit.
It will take three hours for the balloon to rise to 120,000 feet today, which is also the 65th anniversary of when legendary pilot Chuck Yeager broke the sound barrier.
Baumgartner's attempted feat could ordinarily be accomplished only by a supersonic jet, or perhaps the space shuttle. Before the jump, Baumgartner said he was confident he could do it.
The pressure is so low at 120,000 feet that if Baumgartner's suit fails, his lungs would burst and his blood would boil. But the most dangerous moment of the jump will come when Baumgartner opens the capsule door and leaps.
Luke Aiken, the designer of the parachute Baumgartner will be using, said the stunt is even more dangerous than it sounds.
"There's virtually no air. He's in a vacuum. He has no control. If he steps off goofy, if he pushes harder with one foot, it could induce a turn, and that's where we could get into thing that everybody talks about - this flat spin," said Aiken.
Threats of extreme cold, extreme temperature fluctuations and the possibility of an uncontrolled flat spin, which could hit 220 rpm, are all potential dangers of the stunt. The braking parachute could also fail, the spacesuit could puncture and the life support systems could break down.
Baumgartner has successfully leaped twice from lower altitudes, but 120,000 feet will shatter the record set 52 years ago by former Air Force pilot Joe Kittinger, who is now 84 years old.
Baumgartner said he wasn't doing this only to set a record. He's also doing it for science, as the jump could help NASA design better and stronger spacesuits for astronauts.
If his mission succeeds, Baumgartner will shatter several records, including:
First Human to break the speed of sound in free-fall (Mach 1 more than 690 mph)
Highest free-fall altitude -120,000 feet (Joe Kittinger hit 105,000 feet in 1960)
Highest manned balloon flight at 120,000 feet (previous record was 113,740 feet in 1961)
Longest free-fall (Baumgartner's team expects 5 minutes, 35 seconds; Kittinger's was 4 minutes, 36 seconds in 1960)
WATCH THE JUMP LIVE RIGHT NOW: http://www.redbullstratos.com/live/