Quote:
Originally Posted by renormalised
Hardly 
Yes, possible, but not feasible using present technology or any extrapolation of it. To propel a craft weighing one ton to the same speed would require more energy than the entire US uses in several thousand years. Well, at least that's the theory and what the maths tells you. |
I think once a speed can be attain how much energy does it require to stay at the same speed. From what I understand not a lot.
The Plasma rocket which I believe should be ready for testing soon can already predict a trip to Mars lowered to approx 39 days. A leap forward in technology.
http://www.voanews.com/english/news/...123960664.html
These kind of leaps could make near Light Speed possible in the 100years or so.