Interaction between cosmic rays and early life-forms may be responsible for the fundamental property of chirality, or handedness, in biological molecules, according to a paper in The Astrophysical Journal Letters.Cosmic rays are constantly bombarding Earth. When they hit the atmosphere, they degrade into cascades of elementary particles.Many organic molecules such as DNA and RNA can be constructed in left-handed and right-handed versions. In the paper, the researchers propose that the prebiotic soup on ancient Earth produced both left and right-handed versions of these nucleic acids.The paper argues that charged particles from cosmic rays affected right and left-handed molecules differently, conferring an evolutionary advantage on one chirality. This led to life dominated by a single biological handedness.RUNDOWN SHOWS:1. Cosmic rays bombarding Earth2. Cosmic rays degrade into elementary particles in the Earth's atmosphere3. Ancient Earth produced both left and right-handed proto-lifeforms4. Charged particles from cosmic rays affected right-handed and left-handed molecules differently, offering an evolutionary advantage to one chiralityVOICEOVER (in English): In new research published in The Astrophysical Journal Letters, scientists from New York University and Stanford University speculate that the interaction between cosmic rays and early life-forms may be responsible for the fundamental property of chirality in biological molecules.Showers of highly energetic, charged particles from the Sun called cosmic rays are constantly bombarding the Earth. When they hit the Earth's atmosphere, they degrade into cascades of elementary particles.Many organic molecules such as DNA and RNA can be constructed in 'left-handed' and 'right-handed' versions that are mirror images of each other. In the paper, the researchers propose that the prebiotic soup on ancient Earth produced both left and right-handed versions of these nucleic acids.The paper argues that when charged particles from cosmic ray cascades reached the Earth's surface, they affected right-handed and left-handed molecules differently, giving an evolutionary advantage to one chirality. Over time this led to life dominated by a single biological handedness.SOURCES: The Astrophysical Journal Lettershttps://arxiv.org/pdf/1911.02525.pdfhttps://iopscience.iop.org/article/10.3847/2041-8213/ab8dc6


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