Is it true that when people travel to space they lose age relative to the earth?

ie. time travel eg. if there were two people of exactly the same age, one travelled in space for a week, and the other remained on earth, would the one who had been in space be fractionally younger than the one on earth when they returned?

If so how is this possible?

as you speed up time passes more slowly for you. When you approach the speed of light you will barely age while back on earth everyone would have gotten years older. I think there was a twilight zone episode on it.

It's not time travel.

It's the effects predicted by Einstein's Special Theory of relativity.

Very, Very difficult to understand and explain.

In a very condensed explanation of how this works, travel at speeds close to light speed causes "time to slow down"

basically, if something is moving at speeds approaching that of the speed of light, the relativistic effects of time dilation occur.

You reference the "twin paradox."

If space travel got even anywhere close to light speed then we would definetly notice the effects.

That being said, anything that moves experiences time dilation, but on an everyday scale, its so ridiculously, incredibly negligible that we dont need to even think about it.

If you are still interested, there are plenty of books and resources on the web to learn about this stuff.

I would reccomend The New World of Mr. Tompkins by Gamow and Stannard.

You are referring to time dilation, which only happens in humanly measurable amounts if one could travel fairly close to the speed of light. In terms of space flight speeds that humans have attained so far, the differences are a matter of millionths of seconds.

you don't "lose" age so mauch as time slows down. The closer you get to the speed of light the more time seems to slow down.

kind of.

when you are in less gravity time travels more slowly for you, relative to someone else. time ALWAYS moves at the same speed for you. but if you had a calendar with you, and you spent a year in space (idk the exact length of time this would require), when you came back it might be a different date on earth because to them, less time has passed for you.

but no, you cannot go into space and return a year younger. you age less relative to someone on earth. but relative to yourself you feel no difference. if you lived your whole life in space you would live a normal live. but compared to what people lived on earth, it would be longer.

EDIT: other people are right too. speed does the same thing.

This does actually happen. I heard that it was calculated the astronauts that went to the moon are six minutes younger than everyone else. The gps system has to take this time difference into account otherwise they would be inaccurate