ROSWELL, N.M. — A well-known computer scientist parachuted from a balloon near the top of the stratosphere on Friday, falling faster than the speed of sound and breaking the world altitude record set just two years ago.

The jump was made by Alan Eustace, 57, a senior vice president of Google. At dawn he was lifted from an abandoned runway at the airport here by a balloon filled with 35,000 cubic feet of helium.

For a little over two hours, the balloon ascended at speeds up to 1,600 feet per minute to an altitude of more than 25 miles. Mr. Eustace dangled underneath in a specially designed spacesuit with an elaborate life-support system. He returned to earth just 15 minutes after starting his fall.

“It was amazing,” he said. “It was beautiful. You could see the darkness of space and you could see the layers of atmosphere, which I had never seen before.”