NASA, in collaboration with other leading space agencies, aims to send its first human missions to Mars in the early 2030s, while companies like SpaceX may do so even earlier. Astronauts on Mars will need oxygen, water, food, and other consumables. These will need to be sourced from Mars, because importing them from Earth would be impractical in the long term. In Frontiers in Microbiology, scientists show for the first time that Anabaena cyanobacteria can be grown with only local gases, water, and other nutrients and at low pressure. This makes it much easier to develop sustainable biological life support systems.