Oldest and youngest planets of the Solar System have been named: scientists have doubts
The life of the solar system in which we live does not stop for a moment. According to scientists, it was not formed overnight either, so all the planets have different ages - some are older, some are younger.
The IFLScience publication tells how the age of planets is calculated. According to astronomers, about 5 billion years ago, the Sun began to convert hydrogen into helium in its core and thus gradually transformed into a yellow dwarf, the type of star it is today. At the initial stage, the luminary was surrounded by a disc of matter left over from the gas cloud from which the Sun was born. This disc is called the protoplanetary disc. Over time, under the influence of various factors, ice and rock particles began to form in it and gradually merged. This is how planets, comets and asteroids appeared. But which planet was the first?
The first planet in the solar system
Space researchers believe that Jupiter is the oldest planet in our solar system. Calculations show that it was formed in the first 3 million years of its existence. Currently, its mass is approximately 318 Earth masses and it is the largest in our planetary system. At the same time, Jupiter does not orbit the Sun directly. The barycenter between it and the Sun - which is the point around which the two celestial bodies rotate against each other - is not the centre of the star. This point is outside the surface of the luminary.
Researchers consider Saturn to be the second oldest. After it, Neptune and Uranus gained their mass. However, while they were forming, Jupiter and Saturn had already absorbed most of the gas in the outer part of the Solar System.
And finally, four planets with a rocky structure - Earth, Venus, Mars and Mercury - formed closer to the Sun. According to the prevailing theory, Mars formed earlier than the others.
Which planet was formed last
The answer to this question is a bit more complicated. Calculations show that some of the planets went through catastrophic events - collisions with other celestial bodies - to reach their current state. Thus, at the initial stage, the Earth and Uranus looked incomplete. Therefore, they can claim the status of the youngest planet. Their formation was completely completed by collisions with protoplanetary objects that occurred at different times.
It is believed that an asteroid of the size of Mars crashed into the Earth about 4.5 billion years ago. This sent a lot of debris into space, which later turned into the Moon. Meanwhile, the Earth continued to form. It took about a billion years to form the lithospheric plates and oceans, as it is known that they were formed about 3.6 billion years ago. Scientists also know that between 3 and 4 billion years ago, Uranus also experienced a major collision. It was hit by a planetoid the size of the Earth. This caused changes in the internal structure of the planet, which is why it still rotates on its side.
Previously OBOZREVATEL told about an exoplanet that is 16 times larger than Jupiter and may have water.
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