Contents of 7.6 How have scientists determined the age of Earth?

Drawing showing Increasing Temperatures and the earth cooling inward through time

7.6 How have scientists determined the age of Earth?

How long would it take Earth to cool?

Physicist William Thomson (aka Lord Kelvin) attempted to calculate Earth's age based on knowledge of cooling rates from an original molten mass of ~1200o to 3870oC

Fig 7.14

Lord Kelvin's conceptual model gave an age of 20 to 40 million years. Others still disagreed, like paleontologist Thomas Huxley who argued this was still too young, using the "garbage in, garbage out" argument.