For something a bit more realistic, we are still studying nuclear propulsion in fits and starts since we halted its development in the 60s: http://www.nasa.gov

For something a bit more realistic, we are still studying nuclear propulsion in fits and starts since we halted its development in the 60s: http://www.nasa.gov/topics/technology/features/ntrees.html#.U5cQ6i8ikUs http://www.nasa.gov/topics/technology/features/ntrees.html#....