Cosmic rays may be the source of biological 'handedness'

  • Tuesday 26, May 2020 08:48 PM
Sharjah24 – Reuters: 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 pre-biotic 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.