It (the Hadal zone) offers a glimpse of what life on Jupiter’s moon, Europa, might look like. A new species of archaebacteria, Pyrococcus CH1,was recently discovered thriving on a mid-Atlantic ridge within a temperature range of 80 to 105°C and able to divide itself up to a hydrostatic pressure of 120 Mpa (1000 times higher than the atmospheric pressure). Excedrin Migraine won’t help down there.
This discovery was made by an international team of microbiologists of the Microbiology of Extreme Environments Laboratory in partnership with the Institute of Oceanography of Xiamen (China) and the Earth Science Laboratory. This archaebacteria had been isolated from samples by a Franco-Russian team that explored the mid-Atlantic ridge for six weeks searching for new hydrothermal vents.
The piezophilic microorganisms constitute a subgroup of extremophiles. Discovered on the site “Ashadze”(2) at 4100 meters depth, the deepest vent field explored so far, the CH1 strain was successfully isolated and assigned to the genus Pyrococcus, within the Euryarchaeota lineage of the Archae domain. The discovery extends the known physical and chemical limits of life on Earth.
The reason scientists believed for so long that life did not exist in the deepest parts of the sea is because the oxygen that filters down is centuries old, having formed near the surface through photosynthesis by microscopic plants known as phytoplankton.
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