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. 2300 - 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. Assembling this behemoth spaceship wouldn't happen overnight. The time line Kilston has sketched stretches over five centuries, including two centuries for design, one century for construction and one century for test driving the spaceship through the solar system.