How old is the Earth?
The age of the Earth is estimated to be about 4.54 billion years. This estimate is based on a variety of scientific methods, including radiometric dating of rocks and minerals, analysis of meteorites, and observations of the formation and evolution of the solar system.
Radiometric dating involves measuring the ratios of certain radioactive isotopes and their decay products in rocks and minerals. By comparing these ratios to known decay rates, scientists can estimate the age of the rock or mineral. The oldest rocks on Earth, found in Western Greenland, have been dated to be about 3.8 billion years old.
In addition to radiometric dating, scientists have also studied meteorites, which are remnants of the early solar system. By analyzing the isotopic ratios in meteorites, scientists have estimated the age of the solar system to be about 4.6 billion years. This provides an upper limit on the age of the Earth, since it must have formed after the solar system itself.
Overall, the best current estimate for the age of the Earth is about 4.54 billion years, with a margin of error of about 1%. This age has been refined over many years of research and represents a significant milestone in our understanding of the history and evolution of our planet.