[meteorite-list] Speed-of-light question

[Darren Garrison]

On Wed, 26 Aug 2009 08:55:35 -0600, you wrote:

>Engines capable of steady acceleration are not impossible or fictional. They 
>are real and already in use. It is a mere <g> engineering problem to produce 
>one that can operate long enough to reach another star.
>

But the closer an object gets to the speed of light, the higher your inertial
mass becomes-- so you are constantly having to use more and more energy, pushing
harder and harder just to maintain that constant rate of acceleration.  To get
an object with a rest mass infinitely close to the speed of light would take an
infinite amount of energy.  To get a ship merely very close to the speed of
light would take much less energy, say the total energy output of a few galactic
clusters, give or take...