The apocalypse of Earth may not come from the death of the Sun or a galactic collision as predicted by astronomers, but rather from the planet reverting to a state prior to the Great Oxygenation Event.
This statement comes from a study recently published by the Georgia Institute of Technology (USA) and Toho University (Japan), featured in the scientific journal Nature Geoscience.
The research, which is part of the NASA NExSS project, aims to explore the habitability of planets beyond our own, but inadvertently reveals the future of Earth itself.
Earth may return to a deadly state billions of years ago – (Graphic by Christine Daniloff)
According to Science Alert, researchers ran computer models simulating Earth’s biosphere, calculating changes in solar brightness and the corresponding decrease in carbon dioxide levels as gases break down due to rising temperatures.
In the future, carbon dioxide levels will fall into a phase of significant decline, meaning the planet will have fewer photosynthetic organisms such as plants, resulting in reduced oxygen levels. In other words, the planet is “rewinding time” back to the period before the Great Oxygenation Event.
The new model, based on nearly 400,000 biosphere simulations, indicates that this impact will cause a mass extinction for all of us—if humanity still exists at that time—and for other organisms on Earth.
Earth scientist Chris Reinhard from the Georgia Institute of Technology stated in New Scientist that the drop in oxygen levels will be severe, with atmospheric oxygen concentrations being less than one-millionth of what they are today.
This scenario will not occur for at least another million years, but it is still much sooner than previously predicted extinction events, such as the increase in thermal radiation at the end of the Sun’s life that would evaporate all oceans, or the collision between the Milky Way and the Andromeda galaxy, both of which are expected to happen in about two billion years.
