Tardigrades could live there.
“Tardigrades are able to survive in extreme environments that would kill almost any other animal. Extremes at which tardigrades can survive include those of:
Temperature – tardigrades can survive:
A few minutes at 151 °C (304 °F)[51]
30 years at −20 °C (−4 °F)[52]
A few days at −200 °C (−328 °F; 73 K)[51]
A few minutes at −272 °C (−458 °F; 1 K)[53]
Pressure – they can withstand the extremely low pressure of a vacuum and also very high pressures, more than 1,200 times atmospheric pressure. Tardigrades can survive the vacuum of open space and solar radiation combined for at least 10 days.[54] Some species can also withstand pressure of 6,000 atmospheres, which is nearly six times the pressure of water in the deepest ocean trench, the Mariana trench.[22]
Dehydration – the longest that living tardigrades have been shown to survive in a dry state is nearly 10 years,[39][40] although there is one report of leg movement, not generally considered “survival”,[55] in a 120-year-old specimen from dried moss.[56] When exposed to extremely low temperatures, their body composition goes from 85% water to only 3%. As water expands upon freezing, dehydration ensures the tardigrades do not get ripped apart by the freezing ice.[57]
Radiation – tardigrades can withstand 1,000 times more radiation than other animals,[58] median lethal doses of 5,000 Gy (of gamma rays) and 6,200 Gy (of heavy ions) in hydrated animals (5 to 10 Gy could be fatal to a human).[59] The only explanation found in earlier experiments for this ability was that their lowered water state provides fewer reactants for ionizing radiation.[59] However, subsequent research found that tardigrades, when hydrated, still remain highly resistant to shortwave UV radiation in comparison to other animals, and that one factor for this is their ability to efficiently repair damage to their DNA resulting from that exposure.[60]
Irradiation of tardigrade eggs collected directly from a natural substrate (moss) showed a clear dose-related response, with a steep decline in hatchability at doses up to 4 kGy, above which no eggs hatched.[61] The eggs were more tolerant to radiation late in development. No eggs irradiated at the early developmental stage hatched, and only one egg at middle stage hatched, while eggs irradiated in the late stage hatched at a rate indistinguishable from controls.[61]
Environmental toxins – tardigrades are reported to undergo chemobiosis, a cryptobiotic response to high levels of environmental toxins. However, as of 2001, these laboratory results have yet to be verified.[55][56]
Outer space – tardigrades are the first known animal to survive in space. In September 2007, dehydrated tardigrades were taken into low Earth orbit on the FOTON-M3 mission carrying the BIOPAN astrobiology payload. For 10 days, groups of tardigrades were exposed to the hard vacuum of outer space, or vacuum and solar UV radiation.[3][62][63] After being rehydrated back on Earth, over 68% of the subjects protected from high-energy UV radiation revived within 30 minutes following rehydration, but subsequent mortality was high; many of these produced viable embryos.[54][64] In contrast, hydrated samples exposed to the combined effect of vacuum and full solar UV radiation had significantly reduced survival, with only three subjects of Milnesium tardigradum surviving.[54] In May 2011, Italian scientists sent tardigrades on board the International Space Station along with extremophiles on STS-134, the final flight of Space Shuttle Endeavour.[65][66][67] Their conclusion was that microgravity and cosmic radiation “did not significantly affect survival of tardigrades in flight, confirming that tardigrades represent a useful animal for space research.”[68] In November 2011, they were among the organisms to be sent by the U.S.-based Planetary Society on the Russian Fobos-Grunt mission’s Living Interplanetary Flight Experiment to Phobos; however, the launch failed. Tardigrades are one of the few groups to have survived Earth’s five mass extinctions.[69]
Composing members:
0
Composing members:
0
