I have always been interested in the possibility that life could be found beyond the Earth. Science has now found many planets around other suns. It appears that at least some of them may harbor life similar to life on Earth. Chemical building blocks for life have been found in gas nebula. Here on Earth we have found microbial life in very extreme conditions, some of which are miles below the surface of the Earth. Some life forms seem to be able to able to live on a flow of electrons. Other primitive life forms are able to survive high levels of radiation. There may be forms of live vastly different than ours but the possibilities of life similar to ours out in the cosmos look very promising.
In 1991, robots were being used to explore inside of the abandoned Chernobyl Nuclear Power Plant in Ukraine which suffered a catastrophic nuclear accident back in 1986. One surprise was the discovery of black fungi on the inside of the containment vessel. Although most forms of terrestrial life would be damaged by intense radiation levels inside Chernobyl, the fungus seemed to be doing quite well and was especially lush near higher radiation areas.
More than ten years later, Professor Ekaterina Dadachova, then at the Albert Einstein College of Medicine in New York, and her team obtained a sample of the fungus from Chernobyl. One of their discoveries was that the Chernobyl fungi grew faster than other types of fungus when all were bathe in radiation. There were three different species of fungi in the Chernobyl sample including Cladosporium sphaerospermum, Cryptococcus neoformans and Wangiella dermatitidis.
All of these had high amounts of melanin which is a pigment found in many places in nature including the skin of human beings. People with a darker skin tone have higher amounts of melanin. Melanin absorbs sunlight and dissipates ultraviolet radiation. This correlates with people whose ancestors lived in tropical regions that get a lot of sunlight. In the Chernobyl fungi, the melanin also seemed to be absorbing radiation and converting it into chemical energy for biological processes.
In order to discover more about the Chernobyl fungi, the Jet Propulsion Laboratory collected eight species of Chernobyl fungi and sent them to the International Space Station in order to see how they would react to the high radiation environment in space where there is forty to eighty times the radiation found on Earth. The researchers hoped to discover some of the chemical processes that the fungi used to survive and thrive in the high radiation. They might be able to use some of the molecules in the fungi to assist astronauts to survive in space. The results of the experiment have not been published yet.
In a 2008 paper, Dadachgova said that the fungi discovered at Chernobyl are probably not the first of their kind. She wrote, “Large quantities of highly melanized fungal spores have been found in early Cretaceous period deposits when many species of animals and plants died out. This period coincides with Earth’s crossing the ‘magnetic zero’ resulting in the loss of its ‘shield’ against cosmic radiation.” This raises the possibility that somewhere in the universe there might be organisms with high levels of melanin surviving in high radiation environments.