The addition of moss has produced sprouts of peppers, radishes and lettuce on the black carbonaceous chondrite mock substance.
Not only designers, engineers and astrophysicists, but also biologists are preparing for the future exploration of the solar system. In order to maximally provide the inhabited space bases and crews with everything they need for life, they are learning to grow cultivated plants in orbit, on lunar and even Martian soil. And they have recently succeeded in showing that even asteroids can be 'harvested'.
Sherry Fieber-Beyer and colleagues at the University of North Dakota have used a carbonaceous chondrite mimic. Chondrites are the most common type of meteorite falling to Earth and contain rounded silicate inclusions. Carbonaceous ones are not as common and make up less than five per cent of the total number of chondrites. However, they are particularly diverse, containing carbon, nitrogen, potassium and phosphorous, and sometimes simple organic compounds.
Theoretically, when humans start exploiting asteroids' mineral resources, carbonaceous chondrites could provide the soil for growing fresh herbs and vegetables. This has been demonstrated with romaine lettuce, radishes and chilli peppers, plants which have previously managed to grow on board the ISS. Experiments have shown that they grow best if sphagnum moss, which creates numerous water-retaining pores in the ground, is added to the chondrite mimic.
Biologists plan to continue the experiments and will now try to grow mossy peas 'on the asteroid'. The plant is not consumed in large quantities as food but is widely grown to feed grazing animals and to improve field yields. Scientists intend to let them grow, die and decompose in such soil - it is assumed that such a supplement will be more useful than sphagnum. In addition, sending a cargo of pea seeds to a distant asteroid will be easier and cheaper than green moss.
