By Meghan Bialt-DeCelie ’19

Whether the world ends in asteroids or radiation, the big question is what, if anything, will survive. Researchers lead by Dr. David Sloan from the University of Oxford assessed the resilience of species when against three astrophysical catastrophes (asteroids, supernovas, and gamma-ray bursts) that could sterilize the planet.  These events threaten the survival of species with radiation and by deterioration of the ozone layer that is meant to protect life forms from such radiation.

One of the most resilient species found on earth is Milnesium tardigradum, commonly known as the tardigrade. This species can survive with scarce resources, extreme climates, and radiation. The researchers analyzed direct effects of the natural catastrophes that would likely end life such as boiling off the ocean. Taking into account factors such as asteroid mass, ocean volume, and planet density, they were able to use mathematic equations to predict the survival of tardigrades. Because of this incredibly resilient species, researchers predicted that complete destruction of all life on the earth is highly unlikely with a 10-7 chance per billion years.

Even though the sterilization of the planet is not a likely occurrence in the near future, this study can still give insight on how other potential life forms can exist beyond the earth.

References:

1. D. Sloan, R. Batista, A. Loeb, The Resilience of Life to Astrophysical Events. Scientific Reports 7, 1-5 (2017). doi: 10.1038/s41598-017-05796-x
2. Image retrieved from: https://commons.wikimedia.org/wiki/File:201703_tardigrade.svg