A hardy life form called cyanobacteria can grow in otherwise inhospitable lunar soil, new experiments suggest. Future colonists on the Moon might be able to use the cyanobacteria to extract resources from the soil that could be used to make rocket fuel and fertiliser for crops.
NASA plans to send astronauts back to the Moon starting in 2020, with the ultimate aim of setting up a permanent lunar base. Sustaining such a base will be a major challenge, because it is so costly to fly food, fuel and other supplies there with rockets launched from Earth. Every kilogram of resources that could be produced on the Moon itself could therefore help cut costs, making such a base easier to maintain.
That is where cyanobacteria and their amazing abilities come in. Cyanobacteria grow in water-rich environments. They are technically a type of bacteria, but like plants, they produce their own food via photosynthesis. (Sometimes called 'blue-green algae', cyanobacteria are actually not related to the algae they resemble.)
Lunar soil is inhospitable to plants because many of the nutrients it contains are locked up in tough minerals that the plants cannot break down. "It will not be able to support the growth of tomatoes" or other food plants, says Igor Brown of NASA's Johnson Space Center (JSC) in Houston, Texas, US.
But experiments led by Brown show that some cyanobacteria are perfectly happy growing on lunar soil, if supplied with water, air and light.
Brown and his colleagues tried growing a variety of species of cyanobacteria on materials designed to approximate the lunar soil. The simulated soil contained lots of an iron-titanium mineral called ilmenite, for example, which is relatively abundant on the Moon.
The cyanobacteria were taken from hot springs in Yellowstone National Park in Wyoming, US. When put in a container with water and simulated lunar soil, the cyanobacteria were found to produce acids that are amazingly good at breaking down tough minerals, including ilmenite.