Age of the Earth from cooling (Kelvin)
Edad de la Tierra por enfriamiento (Kelvin)
- Date
- 1862 · confidence high
- Place
- Glasgow, United Kingdom
- Credited to
- William Thomson (Lord Kelvin)
- People
- 👤 William Thomson1825–1907
- Field
- Knowledge & symbols
What was discovered
In «On the Secular Cooling of the Earth» Kelvin calculated how long a molten planet would take to cool to today's thermal gradient: between 20 and 400 million years, later 20-40. It was the first physical calculation of the Earth's age; it failed because he knew nothing of radioactive heat and mantle convection.
A wrong but historic result: it strained the debate with Darwin, who needed far more time.
What it led to
- Debate between physicists and geologists on the Earth's age