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The Earth swallowed another planet and (maybe) that's why life exists

The ancient collision that gave rise to the moon may have brought with it all the ingredients needed for life, a new study has shown.

Over 4.4 billion years ago, a Mars-sized body collapsed into a primitive earth and launched our moon into a permanent orbit around our planet.

However, a new study shows that this event could have had a much greater impact than previously thought. Scientists reported today (23 January) in Science Advances (2365) that the collision would have pervaded our planet with the carbon, nitrogen and sulfur that life needs to form. At that time, Earth was a bit like Mars today. It had a core and a coat, but its non-nucleated content was very poor in volatile elements such as nitrogen, carbon, and sulfur. [Science Fact or Fantasy? 20 Imaginary Worlds]

Elements in the non-nuclear parts of our planet called the "bulk silicate earth" can mix with each other, but they never interact with the elements of the nucleus. Although some volatiles were present in the nucleus, they could not get into the outer layers of the planet. And then there was a collision.

One theory is that special types of meteorites, so-called carbonaceous chondrites, collided with the earth, giving the voluminous silicate earth these volatile elements. This idea is based on the fact that the ratios of different versions ̵

1; or isotopes – of nitrogen, carbon and hydrogen correspond to those of meteorites. The proponents of the theory argue that the meteorites must be the source of these elements.

But there is only one problem: the ratio of carbon to nitrogen is eliminated.

While the meteorites have about 20 parts of carbon to one part of nitrogen, the non-core material of the earth, contains about 40 parts of carbon per part of nitrogen. According to study author Damanveer Grewal, a PhD student in the fourth year. Student in the Department of Earth, Environmental and Planetary Sciences at Rice University, Houston, Texas.

The group of study authors therefore decided to test another theory: what if another planet brings the goodies? 19659002] "Earth could have collided with many different planets," Grewal told Live Science. Could one of these planets have given the silicate of the Earth the correct amount of elements?

If this collision had taken place, the two planetary cores would have merged and the two coats would have melted together.

So they wanted to create a possible planet that could collide with our own.

In the laboratory, Grewal and his team created high-temperature high-pressure conditions in a special furnace that could form the nucleus of a planet. In graphite capsules (a form of carbon), they combined metallic powder (which represents the core and contains elements such as nitrogen-bound iron) with different proportions of silicate powder (a mixture of silicon and oxygen intended to mimic the hypothetical planets). Mantle).

By varying the temperature, pressure, and sulfur content in their experiments, the team compiled scenarios of how these elements could divide between the nucleus and the rest of the hypothetical planet.

They found carbon is much less likely to combine with iron in the presence of high concentrations of nitrogen and sulfur, but nitrogen still binds to iron even when there is a lot of sulfur. In order for nitrogen to be released from the nucleus and be present in other parts of the planet, it should have contained very high levels of sulfur, Grewal said.

They then put these options together with information into a simulation of a different volatile elements and the current levels of carbon, nitrogen and sulfur in the outer layers of the earth.

After running over 1 billion simulations, they found that the scenario was the most meaningful – the most probable timing and could lead to a correct ratio of carbon to nitrogen – so there was a collision and fusion of the Earth with a planet in Mars size required, which contained in the core about 25 to 30 percent sulfur.

This theory is "very likely," said Célia Dalou, an experimental petrologist at the Center de Recherches Pétrographiques et Géochimiques in France, who did not participate in the study. "This work is a very successful result of years of research in different teams."

Originally published on Live Science .

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