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Earth's age is approximately 4.54 billion years old, dating back to the formation of the solar system. Its structure is layered, with a solid inner core, a liquid outer core, a thick mantle, and a crust.
Here's a more detailed breakdown:
Age:
Scientists estimate the age of Earth based on radiometric dating of meteorites, lunar rocks, and the oldest known terrestrial materials.
The most precise estimate is 4.54 ± 0.05 billion years old.
This age is consistent with the time of the solar system's formation, when Earth accreted from the solar nebula.
Structure:
Inner Core:
A solid sphere made of iron and nickel, with a temperature of up to 9,800 degrees Fahrenheit (5,400 degrees Celsius).
Outer Core:
A liquid layer of molten iron and nickel, responsible for Earth's magnetic field.
Mantle:
The thickest layer, a hot, viscous mixture of silicate minerals, with the consistency of caramel.
Crust:
The outermost layer, which is thinner under the oceans than on land.
Formation:
Earth formed through accretion, where dust and gas particles in the solar nebula collided and clumped together.
Initially, Earth was a molten ball, and its dense materials, like iron and nickel, sank to the center, forming the core.
As the planet cooled, the outer layers solidified to form the mantle and crust.
Additional Information:
The Earth's surface is constantly changing through tectonic plate movement, volcanic activity, and erosion.
The Moon likely formed from a giant impact with Earth, throwing enough debris into space to create the Moon.
Life on Earth developed within the oceans during the first billion years of the planet's history.
