Time dilation question

[d_stilgar]

If I were traveling out and back to Proxima Centauri at .9 times the speed of light, how would the time dilation work?

At .9x the SoL, time dilation is 2.294. Does that mean that the trip, for me, inside the ship would take about 10 years, but for those on Earth it would seem like almost 22 years? Or would it meant that, to me, inside the ship it would seem like 4.36 years but on Earth it would only be 10 years?

I think the right answer is the first one 10/22 years, but I'm not sure. Thanks.

[Luke122]

Bring me back a tshirt!

[d_stilgar]

The more I think about the more it only makes sense that it would be about ten years for us on earth, but that it would be 4.36 years in the ship.

[The Black Pumpkin]

When traveling near the speed of light, time is supposed to be slower for those at the speed of light than those outside, of course, as you show. But it would still take you 10 years to get there, it would just seem less to you. So I think it's the 4 for your, 10 for everyone else idea.

[BuzzKillington]

This made my brain hurt.

[progbuddy]

You would also have to factor in red shift, as the entire universe is expanding at the speed of light, and all the objects in it are moving apart. So it may take a bit longer than you think ;).

[d_stilgar]

Eh, estimates will do. Thanks guys. 4.3 for me and 10 for everyone else.

[simon275]

http://en.wikipedia.org/wiki/Time_dilation

It is weird but it is true. So if you went on a near light speed flight for a long time you would only age a few years but your kids could easily be in a old age home.