Fleeing earth at the speed of light

Pengwuino
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Ok i was wondering something. Whats the closest planet/moon capable (possibly with human interevention) of supporting life that isn't in our solar system? And If you age slowely nearing the speed of life, wouldn't we be able to leave our solar system and reach another planet if we can go near the speed of light (and we'd age much slower so we could actually live out journey)? I know mass has to go incredibly high but its just a mental excercise :)
 
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We have only begun to find other planetary systems in the last few years. There is virtually NO information about conditions on any of the planets found. So the only answer to your question is "We do not know".

and NO! Your mass would not change if you imbarked on a high speed interstellar journey.
 
Well i meant if we did find one and had to leave Earth and we sent over equipment to sustain life and all that. My main focus on would we make the journey in only a few years of our time even though it might be millions of light years away?

And why does everyone say as your speed -> c, mass - inf.
 
Pengwuino said:
Well i meant if we did find one and had to leave Earth and we sent over equipment to sustain life and all that. My main focus on would we make the journey in only a few years of our time even though it might be millions of light years away?

I think it would be the most cost-effective to colonize Mars. In terms of other habitable planets, however, my guess is that they wouldn't be that far. I would be very surprised, however, if we found one nearby capable of supporting us sans equipment.
 
Pengwuino said:
Well i meant if we did find one and had to leave Earth and we sent over equipment to sustain life and all that. My main focus on would we make the journey in only a few years of our time even though it might be millions of light years away?

And why does everyone say as your speed -> c, mass - inf.
Because they do not understand Relativity?

Suppose you were in a spaceship accelerating away from the Earth with a known constant force applied. To a stationary observer on Earth using the Laws of Newton, the ship's acceleration would appear to be reduced as it neared the speed of light AS IF ITS MASS were increasing. In fact the occupants of the ship may have been on a forced diet and actually lost mass as the journey progressed. The crew of the ship would not experience any reduction in their acceleration nor any change in mass nor would the operation of their lights change. They would note, however, that the Earth was not receding as fast as NEWTON would predict for their rate of acceleration.

The answer is that for relative velocities between 2 objects Newtons laws loose accuracy as you exceed a separation velocity which is a measurable fraction of c. At separation velocities greater then about .1c you must use the Lorentz transforms to correctly surmise the distance traveled.
 
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Pengwuino said:
And If you age slowely nearing the speed of life, wouldn't we be able to leave our solar system and reach another planet if we can go near the speed of light (and we'd age much slower so we could actually live out journey)?
Yes, in theory. See http://math.ucr.edu/home/baez/physics/Relativity/SR/rocket.html .
 
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