A fusion-powered spacecraft could move up NASA's schedule for a manned Mars mission. This type of spacecraft could cut travel time to Mars by more than 50 percent, thus reducing the harmful exposure to radiation and weightlessness.
The building of a fusion-powered spacecraft would be the equivalent of developing a car on Earth that can travel twice as fast as any car, with a fuel efficiency of 7,000 miles per gallon. In rocket science, fuel efficiency of a rocket engine is measured by its specific impulse. Specific impulse refers to the units of thrust per the units of propellant consumed over time.