Life needed a number of ingredients to appear. Apparently these came to be when Earth collided with a planet 4.4 billion years ago.
The giant impact hypothesis postulates that the Moon was created as a result of a collision between a young Earth and a Mars-sized planetoid about 4.4 billion years ago. According to petrologists, this cosmic clash brought around most of the carbon, nitrogen and other volatile elements necessary for the development of life.
By studying primitive meteorites, we know that the Earth and other rocky planets in the solar system are naturally low in volatile elements. Hence these must have come from elsewhere. The time and means by which these components arrive has been debated.
“Our scenario is the first one capable of explaining chronology and arrival agreement with geochemical evidence,” says Rajdeep Dasgupta, co-author of the study in Science Advances. After a series of experiments involving high pressure and temperature, the researchers concluded that young Earth had a sulphur-rich nucleus.
A heart rich in sulphur
While previous theories failed to explain the strange distribution of carbon and nitrogen on Earth, a planet with a sulphur heart would help solve the puzzle. This element would have allowed the dissolution of a large quantity of nitrogen, whereas the carbon would have been less absorbed, resulting in a ratio of 40 parts of carbon for each part of nitrogen, as we see it today on earth.
Using this data, researchers were able to model nearly a billion possible scenarios and confirm the plausibility of their theory. These results not only suggest that the Earth itself would not have been able to see life emerge without outside help, but also provides us with a new avenue of exploration in the study of the conditions of emergence of the earth life.
Check out the video above for more details on the fascinating theory...