Some Surprising Results of What it Would Take to Transport a Million People to Mars

Elon Musk of SpaceX has said he wants to send one million people to Mars. What would it take in terms of the transport side of the equation to actually make this happen?

My good friend Jeffery Greenblatt analyzes emerging technologies to answer questions exactly like this; for example, he recently published a scientific paper in Nature Climate Change on the impact of autonomous cars on greenhouse-gas emissions.

He has now turned his attention to the transport side of getting a large population to Mars:

"We perform the first comprehensive assessment of the energy, resource and infrastructure requirements of a large-scale human transport system between Earth and Mars. In it, we develop credible mass estimates for a system consisting of four appropriately-sized reusable spacecraft to move humans, and four additional types of reusable spacecraft for moving propellant (hydrogen/oxygen and methane/oxygen) from the Moon and Mars to in-orbit depots. Human consumables (air, water, food) and cargo mass estimates were included in the analysis. We base our estimates on public sources, and develop scenarios of infrastructure scale-up to achieve a Mars settlement size of 1 million people by the first half of the 22nd century. We do not examine the requirements of the Mars settlement itself."

His result uncovers some surprising repercussions of such large-scale transport; see his blog post and the paper itself for more details.