Tech-mogul Elon Musk says he knows exactly how long it would take to set up the first city on Mars.
PC Mag and TechCrunch report that Musk says it would take 20 years, and around 1,000 starships, to get the one-million tons of cargo he thinks it would take to build a self-sustaining city on Mars.
It could happen faster except for the fact that Earth and Mars are only lined up right every two years to make such a trip.
Musk himself has said he wants to move to Mars, even though it could be a one-way trip.
He would be in his 70's by the time a Mars city would be ready to live in.