Confessions of a former fireball: How Earth became habitable

A group of researchers at Caltech and Yale have come up with a new theory on how Earth became a planet capable of sustaining life.

The rocks that interacted with seawater in the right way are covered in the theory.

Jun Korenaga is a professor of Earth and planetary sciences at Yale and co-author of a new study in the journal Nature.

The first author of the study is a former graduate student at Yale. The study is based on the final chapter.

The atmosphere on Venus was similar to that of Earth, according to most scientists. Its skies were filled with carbon dioxide, more than 100,000 times the current level of atmospheric carbon.

Scientists agree that life would not have been able to form under such conditions.

There is no rock record from the early Earth, so we set out to build a theoretical model for the very early Earth from scratch.

Their model was built using aspects of fluid mechanics, atmospheric physics and thermodynamics. They came up with the idea that Early Earth was covered with rocks that are not currently on Earth.

The rocks would have been enriched in a mineral called pyroxene, and they would have had a dark greenish color.

magnesium-rich minerals react with carbon dioxide to produce carbonates, which play a key role in sequestering atmospheric carbon.

The researchers suggest that as the molten Earth started to solidify, its hydrated, wet mantleconvected vigorously. The process of pulling CO 2 out of the atmosphere was sped up by the combination of a wet mantle and high-magnesium pyroxenites.

The researchers said the rate of atmospheric carbon sequestration would have been 10 times faster than with a mantle of modern-day rocks.

The rocks on the early Earth would react with the water to create a large amount of hydrogen, which is believed to be essential for the creation of biomolecules.

The effect would be similar to a rare type of modern deep-sea thermal vent, called the Lost City hydrothermal field, located in the Atlantic Ocean. The Lost City field is a prime location for investigating the origin of life on Earth because of its abiotic production of hydrogen and methane.

Our theory has the potential to address more than just how Earth became habitable.

More information: Yoshinori Miyazaki et al, A wet heterogeneous mantle creates a habitable world in the Hadean, Nature (2022). DOI: 10.1038/s41586-021-04371-9 Journal information: Nature Citation: Confessions of a former fireball: How Earth became habitable (2022, March 2) retrieved 2 March 2022 from https://phys.org/news/2022-03-fireball-earth-habitable.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.