Discovery in New Mexico caves changes understanding of the possibility of life on other planets
Kyiv • UNN
Microbiologists have discovered bacteria in dark caves that photosynthesize using infrared light. This expands the boundaries of the search for habitable worlds near red stars.
A scientific expedition to Carlsbad Caverns National Park has led to a sensational discovery that forces astrobiologists to reconsider the criteria for searching for extraterrestrial life. Microbiologists Hazel Barton and Lars Behrendt discovered cyanobacteria capable of photosynthesis without sunlight in the complete darkness of underground canyons. This discovery proves that life can thrive in conditions previously considered unsuitable for energy exchange. This is reported by the BBC, writes UNN.
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Researchers found bright green biofilms on the walls of deep niches. As it turned out, these microbes use not visible light, but near-infrared radiation. While ordinary plants rely on chlorophyll A, cave cyanobacteria use special forms - chlorophyll D and F.
The limestone rock of the caves absorbs the visible spectrum, but for infrared rays it works like a system of mirrors, conducting energy deep underground. Measurements showed that the level of near-infrared light in the most remote corners of the cave is 695 times higher than at the entrance.
The wall was bright green. It was the most vibrant green you've ever seen, and yet the microbes lived in complete darkness
New benchmarks for the James Webb Telescope
This discovery is of fundamental importance for the search for life on exoplanets. The most common stars in our galaxy - red dwarfs (type M) - emit predominantly infrared light. Previously, scientists limited the search area to planets that receive visible light (up to 700 nm), but cave microbes have proven the possibility of photosynthesis at wavelengths up to 780 nm.
Barton and Behrendt are currently preparing a proposal for NASA to determine the limiting light levels required for the survival of such organisms. The data obtained will allow astronomers to significantly narrow down the circle of potentially inhabited worlds among billions of stars, focusing the attention of the James Webb Space Telescope only on those objects where conditions correspond to the new photosynthesis parameters.