On Monday, Oct. 8, Austrian skydiver Felix Baumgartner will attempt to be the first human to break the speed of sound in free fall. He will do this by jumping from an air balloon 120,000 feet above Earth. That's three times higher than the typical cruising altitude of commercial airliners.
After leaping from the capsule, the 43-year-old hopes to reach 690 mph, or Mach 1.
Breaking the speed of sound means passing the speed that sound waves are produced in the air. Sixty-five years ago, Chuck Yeager famously broke the sound barrier flying a rocket plane. Baumgartner won't have the same luxury.