Month: September 2022

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NUCLEAR POWERED LIFE. “Such an organism can potentially thrive in subsurface environments on Mars, Moon, Europa or other planetary systems in the presence of radioactive substances.A comprehensive analysis on the availability of nuclear power for deep surface microbes has also been done.” https://royalsocietypublishing.org/doi/10.1098/rsif.2016.0459 View in LinkedIn

COSMIC RADIATION SOURCE. “In the light of these findings, it is reasonable to propose that instead of or in addition to in situ energy sources, the radiation (potentially supporting radiolysis-based life) can be of cosmic origin. Galactic cosmic rays (GCRs) are charged particles, mostly protons, originating beyond the Solar System. They have relatively lower flux but possess much higher energy than other radiation sources on Earth, and have noteworthy biological effects on terrestrial life and possibly on extrasolar planets.” https://royalsocietypublishing.org/doi/10.1098/rsif.2016.0459 View in LinkedIn

SUBSURFACE SECONDARY PARTICLES. “Upon interaction with a planetary atmosphere or surface, Galactic cosmic rays produce a cascade of secondary particles that include electrons, positrons, gamma rays, neutrons and muons. Muons can travel several kilometres deep below the surface depending on their energy. These secondary particles can induce radiolysis and as described later, possibly power a subsurface ecosystem.” https://royalsocietypublishing.org/doi/10.1098/rsif.2016.0459 View in LinkedIn

DEEP PENETRATION. “If a planet lacks an atmosphere, particles are able to directly strike the surface and the cascade of secondary particles is able to propagate underground. The secondary particles produced in the cascade, such as pions and kaons, are highly unstable, and quickly decay to other particles including beta particles (electrons and positrons) and gamma rays. It must be noted that beta particles and gamma rays are also produced during radioactive decay in underground rock. When charged pions decay muons are produced, and these can travel several kilometres deep depending on their energy.” https://royalsocietypublishing.org/doi/10.1098/rsif.2016.0459 View in LinkedIn

SURACE DESTRUCTION. “Energetic particles are capable of destroying organic materials present in the surface or subsurface environment of planets with thin atmospheres. A number of studies have been devoted to studying the impact of Galactic cosmic rays on the possible destruction of organic matter on Mars. Mars' surface radiation dose is several orders of magnitude higher than that of the Earth due to its thin atmosphere.” https://royalsocietypublishing.org/doi/10.1098/rsif.2016.0459 View in LinkedIn

TOLERANCE TO NUCLEAR RADIATION. “Exposure to high environmental radiation dose also leads to substantial energy expenditure in repairing radiation-induced damage. Bacterium Deinococcus radiodurans is the focus of numerous studies and is the most radioresistant microbe with a lethal dose (LD10) at 15 kGy.” https://royalsocietypublishing.org/doi/10.1098/rsif.2016.0459 View in LinkedIn

OTHER RADIATION EXTREMOPHILES. “Deinococcus radiodurans has a specialized recombination system for DNA repair from ionizing radiation. Interestingly, many fungal species also have very high radiation resistance. Many fungi have 10% survival chance or LD10 values exceeding 5 kGy. Other species, such as Ustilago maydis are also known to have extreme radiation resistance but have a different mechanism to cope with compared with radiation D. radiodurans. For comparison, mammals have very low radiation resistance and a dose between 5 and 10 Gy is lethal.” https://royalsocietypublishing.org/doi/10.1098/rsif.2016.0459 View in LinkedIn

MELANIN PROTECTION. “It has been found that the action of proteins is primarily responsible for the repair mechanism. An abundance of highly melanized fungal spores in the early Cretaceous period deposits has been uncovered, where other plant and animal species have died out. These types of fungi can be found in high-altitude terrains, Arctic and Antarctic regions, and in the Evolution Canyon in Israel.” https://royalsocietypublishing.org/doi/10.1098/rsif.2016.0459 View in LinkedIn

THRIVING ON RADIATION. “Radiotropism is a term used to describe the growth of fungi from exposure to radionuclides. Most radionuclides emit beta (electrons and positrons) and gamma (photons) radiation and studies have shown that exposure to both sources promoted directional growth of fungi. Exposure to 121Sn and 137Cs sources showed that the spore germination in species increased considerably, a phenomenon also known as ‘radiostimulation’.” https://royalsocietypublishing.org/doi/10.1098/rsif.2016.0459 View in LinkedIn