Discovery: Earth Formed After Collision With a Twin Planet

It is probable that the Moon formed 4.5 billion years ago as a result of a collision that nearly destroyed the Earth. This hypothesis was suggested by American astrophysicist Robin Canup. Like a culmination of a large firework, this event became the key one in the process of formation of the Earth and of neighboring planets as a result of collision of sub-planet bodies that lasted for 100 million years.

In accordance with Canup’s theory, a protoplanet of the size of today’s Mars collided at a high speed with the Earth that by that moment was already a formed planet. It is interesting that the protoplanet that hit the Earth was practically its twin. The Moon’s chemical composition speaks in favor of this fact. Analysis of the chemical composition of the Moon revealed that it consists of practically the same material that the Earth, although it was completely formed of the remains of the celestial body that had hit the Earth.

Modeling of the collision revealed that the protoplanet was to have broken to many pieces as a result of the collision. However, after orbiting, these pieces were to have grouped once again in several hours, and a new object was to have collided with the Earth once again. In an interview to BBC Canup said that at that very moment the new object was completely destroyed. Majority of the protoplanet’s remains dropped on the Earth surface to become the last essential component of the planet formation.

But several pieces formed a red-hot disk around the Earth similar to the disks around Saturn. Later, the Moon was formed of this material within dozens of years. Robin Canup thinks that destruction of the twin planet made the Earth such as we know it at present. The most important result of the collision was that the Earth started revolving; this is the reason why now one day lasts 24 hours on this planet and none of the Earth parts gets too hot or cools down very much. It is a key factor that allows life existence on the Earth. The Moon has become a gravitational counterweight for the Earth, it stabilizes a slightly inclined axis of revolution of the planet. This incline of 23 degrees regulates seasonal periods in the nature. Izvestia.ru Translated by Maria Gousseva

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