High above New Mexico, aboard a balloon and gondola named Excelsior III, Air Force Capt. Joseph Kittinger floats up to near-space -- 102,800 feet, or nearly 19.5 miles -- and jumps out. It's part of a research effort to study the effects of high altitudes on the human body, as well as whether test pilots and astronauts could survive should they need to eject from their craft. Kittinger approaches the speed of sound during his descent; it takes him 13 minutes, 45 seconds to touch down.
* Earth's atmosphere, from top to bottom: @