 At 0.1"c", Orion thermonuclear starships would require a flight time of at least 44 years to reach Alpha Centauri, not counting time needed to reach that speed (about 36 days at constant acceleration of 1"g" or 9.8 m/s2).At 0.1"c", an Orion starship would require 100 years to travel 10 light years.The astronomer Carl Sagan suggested that this would be an excellent use for current stockpiles of nuclear weapons.