Gizmo

xantox writes "There are three strategies to travel 10.5 light-years from Earth to Epsilon Eridani and bring humanity into a new stellar system : 1) Wait for future discovery of Star Trek physics and go there almost instantaneously, 2) Build a relativistic rocket powered by antimatter and go there in 22 years by accelerating constantly at 1g, provided that you master stellar amounts of energy (so, nothing realistic until now), but what about 3): go there by classical means, by building a gigantic Ark of several miles in radius, propulsed by nuclear fusion and featuring artificial gravity, oceans and cities, for a travel of seven centuries — where many generations of men and women would live ? This new speculation uses some actual physics and math to figure out how far are our fantasies of space travel from their actual implementation."

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