Archeology SCIENCE

The mysterious cycle of the Great Extinction

Scientists thought for decades that a mass extinction could cycle about every 27 million years but be forgotten.

Recently, this idea once again proved to be valid.

Immediately after the asteroid theory that caused the extinction of the dinosaurs was introduced, researchers began to wonder if it had only happened once.

The Late Cretaceous event is only the most recent of the five (or possibly six) of the extinction catastrophes in place.

Scientists have come up with the idea of ​​a distant planet, nicknamed Nemesis or Shiva, every 30 million years its orbit causes it to disturb the path of many comets in the Oort cloud. , causing many of them to crash into the Solar System so the rate of one of them hits the Earth.

Previous claims of cyclic mass extinction were mainly based on large-scale disappearances of marine life, where fossil records have more information than on land.

To be clear, New York University professor Michael Rampino was the one who searched scientific publications for reports of terrestrial extinction. In Historical Biology, he identified ten events from the past 300 million years, all of which matched a cycle of 27.5 million years. Eight of these are consistent with previously recorded marine extinctions.

Of Rampino’s ten mass extinctions, three date to coincide with the largest crater in 300 million years, consistent with the perturbation theory of comets. On the other hand, eight coincidence with volcanic eruptions may have wreaked havoc on Earth’s atmosphere and temperature.

The biggest challenge is to find an explanation of what mechanism can make these eruptions happen so often, let alone the impact of space.

Rampino and co-authors suggest that the Solar System crosses the galaxy’s mid-plane about every 26-30 million years. They speculate this could be the cause of increased exposure to dark matter, disturbing comet orbits, and possibly having some influence on Earth’s internal processes.

Leave a Reply

Your email address will not be published. Required fields are marked *