One person who would like to see humans living outside the Earth in our lifetime is former astronaut Jeff Hoffman. The technology to reach nearby planets is possible, at least to make the first steps there.

Hoffman is one of around 500 people who have had a unique view of the Earth – he’s orbited the planet. Imagine this: while in space he could put his hand out and block the planet, so everything we know, all of humanity, every person who has ever lived was blocked by his hand. It shows how vulnerable we are. Hoffman thinks that for the long-term survival of our species, we have to become a multi-planet being. The idea of seeding Mars with life is almost an ethical imperative.

Space isn’t far away. If you are in London, you can literally say that space is closer than Paris. Of course you need to expend much more energy to get there. But it doesn’t necessarily have to be that expensive, and we are seeing things happening now, particularly in the private sector developing space transportation that could be the leading edge of a revolution.

Say you wanted to set up a long-term base on the Moon or Mars, what would you need? If it’s going to be sustainable we have to learn to live off the land. But what would that mean? If you take the carbon dioxide in Mars’ atmosphere and water which we know exists, and you combine that with a little bit of 19th Century chemical engineering, you have water to drink, oxygen to breathe, with the methane and oxygen you actually have made rocket fuel.

A lot of the forces that shape our society here on Earth would be fundamentally altered by living on another planet. You would set up new types of social situations, new types of philosophy, politics who knows what would evolve. Doing something like taking life from the earth and bringing it to other places would be an enormously revolutionary step, not just in human evolution but also in evolution in life.

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