>"Of course, eventually all energy sources on earth were solar originally" I originally came to reply "Not geothermal". But just read up a bit and found out o

>"Of course, eventually all energy sources on earth were solar originally" I originally came to reply "Not geothermal". But just read up a bit and found out only a fraction of geothermal heat came from Earth's gravitational collapse. The bulk of the heat is from radioactive decay. Which of course was sourced from stellar fusion.