Science: 100 Million-Mile Test

At the World Congress of Flight, which the Air Force assembled last week among the slot machines of Las Vegas, Nev., Dr. Edward Teller described a scheme to explode a nuclear charge 100 million miles away from the earth. The purpose would be to test a key assumption of Einstein's theory of relativity: that every kind of electromagnetic radiation (light, infrared, ultraviolet, radio waves, X rays and gamma rays) travels at the same speed—186,000 miles a second.

If the nuclear charge is exploded 100 million miles from the earth, it will release all kinds of radiation at the same instant. According to relativity theory, the waves should still be traveling together when they reach the earth nine minutes later. But if gamma rays, for instance, prove to travel measurably faster than infrared through the vacuum of space, relativity, the supreme law of the universe, will have to be revised.

This spectacular experiment is not scheduled, only talked about. But it should not be too difficult to perform. A powerful nuclear charge need only be blasted free of the earth and set in orbit around the sun. Since its speed will not be the same as the earth's, it will move steadily away. When it gets far enough, it can be exploded by a radio signal or a timing mechanism.