What Happens to Time When You Travel Near Light Speed?

Imagine you're on a super-fast spaceship, like a rocket going almost as fast as light. When you go this fast, time moves more slowly for you than it does for someone who stays behind on Earth. So when you come back from your trip, you might have aged less than the people you left behind, even though you both think time passed normally. It's like watching a clock move slower while you're moving really fast.

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Examples

  1. If you zoom through space at almost light speed, you'll age more slowly than your friends back home.
  2. Imagine watching a clock in a fast-moving train, it seems to tick slower than one that's still.
  3. A spaceship traveling for what feels like a few days might actually be gone for decades on Earth.

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