Source: Lockheed Martin
quote: Worth pointing out there's been basic designs for interplanetary ships for decades as well. If we weren't hung up on anything with the word "nuclear" in it, Mars suddenly becomes just a 2 or 3 week trip away.
quote: In fact, thats the main thing I think we lack between us and the original Enterprise or a Babylon 5 sort of Earth ship; energy so cheap as to be an afterthought. If it weren't so expensive to kick things in to orbit, then everything else for a ship that didn't care to leave the solar system is in place or close to in place.
quote: 4.24 light years / 100 years = 0.0424c = 12,711 km/sec.
quote: To put something into low earth orbit, you "only" need to reach about 8 km/sec. Energy goes as the square of velocity, so to get a spacecraft to the nearest star within 100 years, you'd need (12711/8)^2 = 2.5 million times as much energy as needed to put the craft into low earth orbit.