[sacred_numbers]

Mars will certainly be challenging to colonize, but it has some major advantages that I believe outweigh the disadvantages.

First, water is pretty abundant almost everywhere on Mars.

Second, carbon is abundant and nitrogen is abundant enough to make food and plastic production viable.

Third, Mars has an atmosphere which is thick enough to provide some protection from radiation and meteorites but thin enough that conductive heat loss isn't too big of a concern. Also, aerobraking massively decreases the amount of fuel required to get to Mars.

Fourth, Mars probably has enough gravity to prevent most of the health risks associated with low gravity.

I don't think either Mars, the Moon, or asteroids are dead ends for colonization. In the long, long run I think more people will live in rotating habitats in cis lunar space than on Mars, and more people will live on Mars than the Moon, but I think there are enough resources for millions or perhaps billions of people to live on Mars.

[WalterBright]

What Mars lacks is a source of power. The solar incidence may be too weak to support much of anything. No fissile materials have yet been discovered there.

The Moon has plenty of solar to harvest.

[qayxc]

> What Mars lacks is a source of power. The solar incidence may be too weak to support much of anything.

Says who? The solar constant on Earth is about 1360 W/m².

Due to the atmosphere, only about 1025 W/m² actually get to the surface.

Mars, just from applying the inverse-square law has an average solar constant of about 589 W/m². Due to the lack of clouds and thin atmosphere, most of that reaches the surface.

So basically you get more than half the energy per unit area than on Earth. Coupled with batteries or power-to-gas and even wind power, I see no major power problem on Mars.

It's not as if there's a lack of usable land for solar arrays or big stacks of batteries on Mars...

[Symmetry]

The battery issue really cuts against most places on the Moon. Getting through 12 hours of night is a lot easier than getting through 2 weeks of night. There is the peak of eternal sunlight on the Moon's south pole where the sun marches around the horizon forever[1] but the lunar night is a big challenge everywhere else.

[1] And right next to an eternally shadowed crater we know has hydrogen, probably in water.