Two jumps down, one to go for Felix Baumgartner, the 43-year-old Austrian who is trying to become the first human to break the speed of sound while in freefall and live to tell the tale.
After weather delayed his second test jump for two days, Baumgartner jumped from 18 miles—about 96,640 feet—above the Earth's surface on Wednesday. Next month, Baumgartner will push that up to 120,000 feet, which would break Joseph Kittinger's long-standing record for highest skydive of 102,800 feet, set in 1960 as part of an U.S. Air Force research project. In March, Baumgartner successfully jumped from 71,581 feet above the Earth's surface as a warm up for next month's jump.
Baumgartner fell for nearly four minutes before deploying his parachute. He was wearing a newly-designed fully-pressurized suit that researchers hope could allow astronauts to re-enter the atmosphere without a spaceship in case of emergency.
At altitudes above "Armstrong's Line," about 60,000 feet above Earth's surface, water boils at human body temperature, making any unsuited exposure fatal within a few seconds.
Baumgartner, who first jumped out of a plane at age 16, says he's long had his sights set on Kittinger's record. Now it's within reach.
"When you're a skydiver for so long, you're always looking up at the benchmark Joe Kittinger set in the 60s," he said in a May interview with U.S. News.
Dubbed the Red Bull Stratos project, Baumgartner and the team of scientists supporting him have been preparing for the jump for nearly five years. Baumgartner has an impressive skydiving and BASE jump resume, having jumped off Rio de Janeiro's Christ the Redeemer statue, off a series of skyscrapers, and into a pitch black cave in Croatia.
"At a certain point [what I was doing] wasn't challenging anymore," he says. "I felt kind of lost because jumping off another 'highest building,' the preparation is always the same. Now, everything is fairly new—it's a new mountain to climb."
Kittinger is part of Baumgartner's team and says he's excited to see the record fall.
"I had no idea it'd be 52 years [before the record was broken]," Kittinger says. "Felix is the perfect guy to do it. He's an incredible, trained professional athlete, and he's dedicated to making a scientific contribution."
Jason Koebler is a science and technology reporter for U.S. News & World Report. You can follow him on Twitter or reach him at firstname.lastname@example.org