If the human race is to survive in the long-run, we will probably have to colonise other planets. Whether we make the Earth uninhabitable ourselves or it simply reaches the natural end of its ability to support life, one day we will have to look for a new home.
Hollywood films such as The Martian and Interstellar give us a glimpse of what may be in store for us. Mars is certainly the most habitable destination in our solar system, but there are thousands of exoplanets orbiting other stars that could be a replacement for our Earth. So what technology will we need to make this possible?
We effectively already have one space colony, the International Space Station (ISS). But it is only 350km away from Earth and relies on a continuous resupply of resources for its crew of six. Much of the technology developed for the ISS, such as radiation shielding, water and air recycling, solar power collection, is certainly transferable to future space settlements. However, a permanent space colony on the surface of another planet or moon adds a new set of challenges.