Space Daily May 18, 2026 • 00:38

The ISS travels at 17,500 miles per hour, which means astronauts inside it are aging measurably slower than people on the ground, and by the time Scott Kelly returned from his year in orbit he was 5 milliseconds younger than his identical twin brother Mark. - Space Daily

The ISS travels at 17,500 miles per hour, which means astronauts inside it are aging measurably slower than people on the ground, and by the time Scott Kelly returned from his year in orbit he was 5 milliseconds younger than his identical twin brother Mark. - Space Daily

At 17,500 mph, the ISS produces real relativistic time dilation. After 340 days in orbit, Scott Kelly returned roughly 5 milliseconds younger than his identical twin brother Mark, a tiny but measurable confirmation of Einstein's special relativity in human fl…

Scott Kelly came home from 340 days on the International Space Station in March 2016 fractionally younger than the brother he had left behind. Not metaphorically. Measurably. By the calculation NASA … [+9662 chars]

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