Nuclear powered LEDs may be key to exploring the universe
The cost of putting a pound of material of any sort in orbit is extraordinarily high. In fact, the cost is so high that simply getting enough food and water into space to support an extended expedition to the moon or Mars is a huge barrier to space exploration. Many scientists believe the only way we'll ever be able to spend extended periods on the moon or on the surface of Mars is for astronauts to be able to grow their own food.
The problem is that radiation levels on the surface of the moon, and the surface of Mars combined with other hazards would prevent astronauts from simply being able to grow the food on the surface. Scientists believe that astronauts would be able to grow food inside heavily shielded greenhouses or possibly inside lava tubes used as ready-made moon bases.
The key to growing food in such structures would be getting the sunlight for plants to be able to carry out the required photosynthesis. The answer to being able to have plants on the moon that can survive long winter nights could be nuclear powered LEDs. According to scientists, during the two-week long solar day, refracted sunlight can be funneled underground or into greenhouses to nourish plants. However, the nuclear powered LEDs would be needed to make it through the two weeks of night.
Scientists believe that a practical solution would be to use a radioisotope thermoelectric generator similar to what is powering the Mars Science lab to allow the LEDs the last two weeks. The plants would pull double duty for the astronauts providing food, scrubbing carbon dioxide from the atmosphere, and replacing it with oxygen to breathe. On Earth, 50 square meters of plant materials are needed to provide the required food and oxygen for one human. However, it's unclear if plants will grow on the moon even using nuclear LEDs at the same rate they grow on earth. Scientists hope that astronauts would be able to produce water on the planet, but if not it would have to be brought from Earth and continually recycled.
[via Forbes]