Should we leave the Earth? It’s the age-old question we have asked since we first gazed toward worlds beyond our own.
With 21st century technology, that reality is closer than ever to being realized. Critics of the idea will say that we have problems here on Earth to solve before we go out into the universe. They may have a point, but the reality is that we will always have problems on this planet, and with the current state of the world, now is a better time than ever.
Of where to go, Mars makes the most sense due to its relative proximity, thin atmosphere, and relatively strong gravity compared to other options. The Moon seems like a better option at a first glance, being closer to home, but it actually takes a similar amount of fuel to land on Mars, because its atmosphere can be used to assist in slowing down a lander. The Moon’s atmosphere is too thin to wear down the sharp, jagged dust particles that make up its surface, which could wreak havoc on the complicated machinery needed to keep a base up and running.
Now that we know that Mars is the most likely target for the second home of humanity, we have to know the risks involved with such a journey. One of the largest risks an explorer would face would be the radiation that comes from space. The easiest way to counter it would be burying the habitats under a layer of dirt to protect it. Solar flares are another radiation issue. Large solar flares can cause death from acute radiation exposure, so some kind of shelter would be required for the spacecraft during the transfer between Earth and Mars, and for the habitat on the surface in case of a solar flare.
Self-sustainability is a big issue, but isn’t as pressing of one, because initial colonies will almost certainly rely on getting supplies from Earth. One of the most important ways to become more self-sufficient is the Sabatier reaction, which uses carbon dioxide and water to produce methane and oxygen. Methane and oxygen can then used for fuel and breathing. Carbon dioxide can be found easily in the Martian atmosphere, and subsurface water is not uncommon.
Leaving our comfortable home for other worlds is an extremely difficult challenge, possibly the most difficult challenge of them all for humanity. If we do accomplish it, though, it would be the inspiration for a generation to strive past their individual issues, and work towards a greater good, much like the moon landing was. When you look into it, the biggest obstacle to us going out into the universe isn’t radiation, supplies, or anything other than funding. The real question is: can we afford to leave the Earth? Not “should we?”