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Science: Fountain of Youth

2 minute read

Not only did time seem to pass slowly for Astronauts Frank Borman and James Lovell aboard Gemini 7 last month. Time actually slowed down for them, says Rice University Space Science Professor Robert C. Haymes. While orbiting the earth for 330 hours, figures Haymes, the astronauts aged a thousandth of a second less than men on earth.

Haymes calculated Gemini 7’s time slowdown by using a formula from Einstein’s 1905 Special Theory of Relativity. According to the theory’s “time dilation effect”—which has since proved true for high-velocity nuclear particles —time slows down for an object as its speed increases. At Gemini 7’s orbital velocity of about 17,500 m.p.h., Haymes explains, the effect on the astronauts was “not biologically detectable.” But at velocities approaching the speed of light (186,000 miles per second), the slowdown would become more dramatic.

At a constant speed of 170,000 miles per second, says Haymes, a future astronaut would need more than nine years for a nonstop round trip to the star nearest the sun, Proxima Centauri. Because of the high speed, however, time would be slowed aboard the spaceship, and only a little more than two years would pass during the trip. On his return to earth, the astronaut would actually be about seven years younger than a twin brother he had left behind.

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