In order to learn more about Mars and the origins of life, astronauts will have to stay on the planet for long periods. But will it be possible for humans to live on Mars?
　One of the biggest challenges will be to transport materials to Mars to build living facilities there. Transporting heavy construction materials from Earth will be far too difficult and expensive. So some architects, including a Japanese couple, came up with the idea to use the large supplies of underground water on Mars. If the water is brought up to the very cold surface, it will quickly freeze and become solid ice. The astronauts can then use the ice to build houses. In this way, only items such as drilling equipment and 3D printers will be necessary to shape buildings from the ice.
　In 2015, this idea won NASA’s contest for the best way to construct buildings on Mars.