How Old the Planet Earth Is
Earth is the third planet from the sun and the only one, as far as science knows, that has life on it. Since ancient times, our ideas of how the Earth formed and developed have continued to change, but when radiometric dating appeared in 1905, it became possible to establish the approximate age of our planet.
5-Minute Crafts would like to tell you about how the universe, our solar system, and planet Earth have formed.
How old the universe is
According to modern scientific concepts, the observable universe emerged about 13.799 ± 0.021 billion years ago.
At first, the universe was in a state of singularity, which is characterized by an infinite density and temperature of matter. Then, after the Big Bang, it began to expand and cool continuously. The first galaxies, stars, planets, and other objects of the universe began to form from the resulting matter.
How old the solar system is
According to rough estimates, our solar system is 4.568 billion years old. The oldest inclusions found in meteorites date from this age.
First, a nebula formed from a large swirling cloud of interstellar dust and gas. It consisted of helium, hydrogen, and other heavy elements. When the cloud began to accelerate, it flattened into a protoplanetary disk under the influence of gravity. From it, protoplanets began to form, orbiting the center of the nebula.
Soon, the center of the nebula collapsed. During compression, it heated up until nuclear fusion of hydrogen into helium began. After more contraction, the young star ignited and evolved into the sun.
At the same time, in the outer part of the nebula, gravity caused matter to condense, and the rest of the protoplanetary disk began to split into rings. As a result, accretion began — the process where the mass of celestial bodies is increased by the gravitational attraction of matter from the surrounding space. Thus, planets were formed from large debris and dust fragments.
How old planet Earth is
According to the generally accepted scientific hypothesis, the Earth formed about 4.54 billion years ago. The process of its formation was completed within 10 to 20 million years.
The proto-Earth grew by accretion until its interior was hot enough to melt the heavy metals. This resulted in the separation of a primitive mantle and a metallic core, producing the layered structure of the planet just 10 million years after its formation. In addition, it marked the beginning of the formation of Earth’s magnetic field.
At the beginning of its history, Earth was quite hot and inhospitable for all life forms. Soon after its formation was completed, about 4.1 billion years ago, a period of intense meteorite impacts began. It ended about 3.8 billion years ago, after which the Earth began to cool. It’s believed that about 3.5 billion years ago, life already existed on the planet. At least the oldest fossils date back to this period.