But the technological hurdles, Kilston readily admits, aren't small. The biggest probably would be the engines. Kilston imagines some sort of powerful fusion rockets. Even at the Project's relatively slow speeds, speeding the spaceship up at the beginning of the voyage and slowing it down at its destination would consume more than 99.9 percent of its 8 million tons of hydrogen fuel. Powering the ship and keeping its 1 million people alive and happy for 10,000 years would take only the remaining 0.1 percent.
People ponder interstellar travel.
Basic research, a Mars colony lays the foundation. A detailed design for an interstellar spaceship is created. Prototypes of the fusion engines, repair robots and other technologies are built and tested. The 100 million tons of material necessary are gathered and construction begins. The completed spaceship takes a century-long test cruise through the solar system.