Cosmic rays left an indelible mark on young Earth

Cosmic rays left an indelible mark on young Earth – in particular, on ancient proto-organisms. This conclusion was made by researchers at Stanford University, whose work was published in the journal Astrophysical Journal Letters.

In a new work, researchers hypothesize that cosmic rays are responsible for the chirality of biological molecules that existed on the early Earth. Chirality is the absence of symmetry characteristic of all animals with respect to the right and left sides.

Like the left and right hand, two chiral forms of one molecule reflect each other but do not line up if stacked together. If the mirror version of a molecule replaces the normal version in a biological system, the system will often malfunction or completely stop functioning. Louis Pasteur discovered chirality in 1848 – scientists have since debated whether it was caused by chance or by any determinative influence.

“We assume that the biological orientation that we are now observing on Earth is due to evolution under conditions of magnetically polarized radiation, where a tiny difference in the speed of mutations could contribute to the evolution of DNA-based life, rather than its mirror reflection”.

Noemi Globe, lead author of the research

If the scientists hypothesis is true, then all life in the Universe has the same chirality – since it is formed under the influence of cosmic rays.