Attention, Frisbee fanatics: Your beloved airborne disk is dangerously close to fizzling out as the high-flying king of fling. Gliding onto the scene is the "Astonishing Flying Ring"—also known as Aerobie—a plastic circle that has already broken the Guinness World Record by sailing 1,046 feet, 11 inches (nearly a fifth of a mile), the longest distance any object heavier than air has ever been thrown.

The creator of the ring is Alan Adler, 47, a Palo Alto inventor and high-tech consultant. Last December his company, Superflight Inc., began distributing the Aerobie along with the offer of a $1,000 prize for the first documented record-breaking throw. Before Adler could say ETA, the bright orange rings were zooming over Silicon Valley campuses. A month later Scott Zimmerman, a computer programmer from Pasadena and a four-time World Frisbee Champion, threw the Aerobie to its record distance. Later Zimmerman stood in the Rose Bowl and threw several Aerobies out of the stadium for astonished newsmen.

The Aerobie's brisk sales (120,000 so far, at $7.95 per) represent vindication of a sort for Adler. A tinkerer all of his life, he holds more than 20 patents for parts of nuclear reactors, jet engines and computers, and has designed his own sailboat, but he has never had such a popular success. "I don't own a jet engine or a nuclear reactor, so my inventions really had no aesthetic appeal to me," he says. "I really wanted to make something I and others could use and have fun with."

In the early '80s he created the Skyro, a forerunner of the flying ring. Parker Bros, marketed it with moderate success, but Adler was never happy with its flight pattern; at speeds too high or low it tended to veer off course. Last year he went back at it and, after consulting with NASA and aerodynamicists at Stanford (where he lectures in mechanical engineering), he added an outside circle of rubber that brought the ring into balance.

Adler, who is married and has two grown children, is now working on a new flying toy. He won't say what it is but hints: "It will fly very slowly to provide the illusion of levitation, which I find particularly intriguing. It will have a magical quality."