Should We Colonize Mars?

Two Planets That Look Alike and Aren't

Five minutes of writing on what you already think, then the numbers. Mars has about a third of Earth's gravity, an average temperature of −60 °C, and roughly a hundred times the surface radiation. Earth's air is 21% oxygen; Mars's is 0.1%.

Then the history — Sputnik in 1957, Gagarin and Kennedy's challenge in 1961, Apollo 11 in 1969, the first lander on Mars in 1976, the Challenger disaster, the space station, SpaceX.

And then the reason people take this seriously. An asteroid ten kilometres across ended the dinosaurs 66 million years ago, and impacts like it have historically arrived on something like a 26-million-year cycle. Four other mass extinctions have happened in the last 500 million years. Yellowstone sits on a supervolcano that erupts roughly every 600,000 years and last erupted about 600,000 years ago. The argument for Mars is that everything we are is currently stored in one place.

Three Positions, Not Two

You'll work in a small group around one of these:

• Colonize. One planet is one point of failure. And space programs have a track record of producing things we use here — LASIK eye surgery, water purification, solar cells, GPS. Neil deGrasse Tyson's version: it's worth it if it pulls an entire generation into science, and "the next generation of astronauts to land on Mars are in middle school now."
• Explore, but don't move in. Perseverance has been driving around a Martian crater since 2021 with nineteen cameras, two microphones, and a helicopter — looking for exactly the evidence of ancient life we say we want. Maybe we don't need to live there to find it.
• Don't go. Too expensive, too dangerous, and no life worth living at the end of it. A study found that establishing a colony is currently infeasible: some of the necessary technology doesn't exist, there's no workable plan for growing enough food, and the first colony's cargo would take more than thirteen heavy rocket launches.

What living there would be like: underground most of the time because of the radiation, almost no direct sunlight, gravity under half of Earth's — which means muscles waste and bones thin — mostly freeze-dried food shipped from Earth, very little privacy, and a small group of people a very long way from everyone else.

The question at the centre of the week: should we care whether humanity still exists millions of years from now? Almost everyone says yes immediately. Try to explain why — it's harder than it sounds, and that difficulty is the interesting part.

Open the Discussion

• Why do humans explore at all? Why do we accept the risks?
• Would you sign up to be one of the first colonists? Would going be anything like being one of the first settlers at Jamestown?
• How seriously do you take the risk of an asteroid, a supervolcano, or a nuclear war? Should we be preparing harder — and is Mars a sensible way to prepare?
• If we go: a joint mission of many countries, an American race like Apollo, or private companies competing? And should any part of Mars belong to whoever gets there first?

Before you leave, find a resource of your own to bring on Thursday.

What Could Be Lost

Share what you found, then take the hardest question of the week: what are the downsides of trying to colonize Mars? What could we lose by going?

Think about the money not spent here, the people who wouldn't come back, the scientific value of a planet nobody has contaminated, and whether treating Mars as a backup makes us careless with the planet we have.

And one more: what would actually change for humanity if we found evidence that something once lived on Mars?

Score Your Own Week

What went well, what to improve, what you learned, and whether anything you believed changed. Then the participation matrix. Be honest with yourself.