Trade and Commerce

By virtue of proximity, Mars is uniquely positioned to support exploration and trade in precious metals from the asteroid belt. These might be recovered in large quantities without the environmental degradation that occurs when they are extracted on Earth. As Zubrin says, the main asteroid belt "contains thousands of small bodies that are far richer in platinum group metals than the best ore on earth."

Regarding Mars as a hub for commerce, in his book, The New World on Mars, Zubrin writes, "The sure way to make money in a gold rush is not to mine the gold yourself, but to sell blue jeans to the gold miners ... What Seattle was to the Yukon, Mars can be to the asteroids." With a sufficient degree of settlement and development, Mars can be the grocery and hardware stores of the asteroid belt, providing food, fertilizer, fuel, and even rocket propellant.

Mars lost a lot of water through the eons, but this had a side effect that will be commercially useful. Water containing the normal, lighter isotope of hydrogen was preferentially lost. As a result, water on Mars today is richer in heavy water, which contains the isotope of hydrogen known as deuterium. That will become important as fuel for fusion reactors.