New research shows that Earth’s geology is influenced by comets that fall every 200 million years as the planet passes through the spiral arms of our galaxy.
Scientists believe that Earth’s journey through the Milky Way may have greatly affected the planet’s geology. Scientists have come to the conclusion that during the passage of the planet through the spiral arms of the Milky Way, every 200 million years, comets fall to Earth, which change the continental crust of the Earth, writes Space.
In our galaxy, all objects revolve around the center of the Milky Way. Spiral arms, one of which contains the Solar System, also revolve around the galactic center. But our star system does this much faster than the sleeves themselves.
For example, the Sun rotates around the center of the galaxy at a speed of 863,000 km/h, and the spiral arms at a speed of 76,000 km/h. This means that the Solar System and all its components, like other stars and star systems, are constantly entering and exiting the spiral arms.
As the Solar System moves through the spiral arms of the galaxy, icy objects in the Oort Cloud, located at the edge of the system about 7.4 trillion km from the Sun, interact with the dense gas clouds of the galactic arms. This interaction causes comets to head towards the inner part of the solar system, where Earth is located.
These comets are much more energetic than asteroids, whose fragments, and sometimes themselves, are constantly falling to Earth. Therefore, the fall of comets causes a greater change in the geology of the Earth, scientists believe.
“We believe that comets that fall to Earth every 200 million years are responsible for changes in the Earth’s crust. We came to this conclusion after studying zircon crystals discovered in Greenland and Australia. It is here that you can find the oldest rocks from the early history of the Earth,” he says. Chris Kirkland of Curtin University, Australia.
Scientists used the decay of uranium in zircon crystals to create a geological time scale of Earth’s history that spans 1 billion years, from 2.8 to 3.8 billion years ago. This timeline can help geologists learn how Earth became the only known planet to have continents and active plate tectonics.
Scientists have discovered a regularity in the change in the formation of the Earth’s crust and believe that it is connected precisely with the fall of comets. Scientists believe that Earth’s journey around the galactic center helps shape the planet’s geology. Their models of the formation of the Earth’s crust showed that over billions of years all changes corresponded to the galactic year. This is the time it takes for the Solar System to make a complete revolution around the center of the Milky Way, and it is approximately 200 million years. But for now this is just a theory that needs proof and further research, scientists say.