World Age

What is Earth?

Earth is the third planet from the Sun and the fifth largest planet in the Solar System. It is the only planet known to have life, and it is home to millions of species of plants and animals. Earth is a terrestrial planet, meaning it is composed of land, air, and water. Its atmosphere is composed of nitrogen, oxygen, and other gases, and its surface is covered in oceans, deserts, forests, and mountains.

How old is Earth?

Earth is estimated to be about 4.54 billion years old. This age is based on radiometric dating of meteorite material and is consistent with the ages of the oldest-known terrestrial and lunar samples. Scientists have developed a geologic time scale to organize the timing and relationships between events that have occurred throughout Earth’s history.

The oldest rocks on Earth found so far are the Acasta Gneisses in northwest Canada. These rocks are dated to 4.03 billion years old, making them the oldest known rocks on the planet. Other age-dating techniques have been used to determine the age of Earth. Radiometric dating, which uses the decay of certain elements, has been used to date rocks from Earth and other planets.

Earth is the only planet in our solar system that has an atmosphere capable of sustaining life. Its age is estimated to be 4.54 billion years old, based on radiometric dating of meteorite material and is consistent with the ages of the oldest-known terrestrial and lunar samples. The oldest rocks on Earth found so far are the Acasta Gneisses in northwest Canada, which are dated to 4.03 billion years old. Scientists use a geologic time scale to organize the timing and relationships between events that have occurred throughout Earth’s history.