For Matthew Tibbetts, a Franklin & Marshall College senior and astrophysics major, large scale is the only way to consider building human habitats on Mars.
"There are plenty of concepts on the first Mars base we're going to build and they tend to be very conservative in scale, very tiny pods just dropped on the surface, enough for just six or seven people for a short period of time," said Tibbetts, whose research project is designing and building a base model.
Tibbetts, who this fall will begin a five-year, graduate-school program in aerospace engineering at Washington University in St. Louis, said there are four stages for establishing human inhabitation of Mars.
"The first stage is putting humans on the planet, the second stage is sustainability, which is a huge leap, the third stage is population growth, and the fourth stage is self-governance," he said.
In deciding on the size of the Mars base he would design, Tibbetts said, "I wanted to do something a little more ambitious since I had no real-world constraints at all. So, I decided to go with the second stage."
To build a facility where sustainability is already achieved on a planet 249 million miles from Earth, Tibbetts researched the various ideas scientists have proposed over the decades about Mars habitation.
"There were a lot of competing theories, but I locked onto one paper from the late 1990s that argued the traditional idea of domed cities was inefficient in terms of materials," he said. "The best way to build a base is to build mostly torus, or donut-shaped, buildings."
Tibbetts said his model for a Martian "test colony" would have six torus buildings, the structures of which would be half submerged into the planet's surface and the bottoms filled with regolith or Martian dirt.
How to survive on Mars without getting constantly resupplied from Earth? Tibbetts said he has relied on several theoretical ideas such as a nuclear cell and solar panels to provide energy.
"To make air, water and food, you can strip hydrogen from the dirt and bring oxygen from Earth," he said. "My model would have a greenhouse, and house 150 scientists for three years to research, experiment and explore."
His buildings also would have one feature he said is vital for humans – a small dome so people can see the Martian sky.