Cenozoic Era · Paleogene Period
Earth 35 Million Years Ago: The World Starts to Cool
Earth 35 million years ago: two asteroid impacts, a cooling climate and Antarctica about to freeze over at the end of the Eocene.
Spin it in 3D and move through timeMap: Ancient maps: PALEOMAP PaleoDEMs (Scotese & Wright 2018), CC BY 4.0 · Natural Earth.
About 35.7 and 35.5 million years ago, two large asteroids struck, making the Popigai crater in Siberia and the Chesapeake Bay crater in Virginia, each tens of kilometres or more across.
The climate was cooling. As Australia and South America pulled away from Antarctica, ocean gateways opened around it and carbon dioxide levels fell. About 34 million years ago, at the Eocene–Oligocene boundary, a permanent ice sheet began to grow on Antarctica.
That moment marks the start of the “icehouse” world we still live in. Many warmth-loving animals and plants died out in the change.
Events of the time
Popigai impact
35.7 million years ago · Siberia, Russia
A 100 km crater whose shocked rocks contain diamonds. Chesapeake Bay was struck within about a million years of it.
Antarctica freezes over
34 million years ago · Antarctica
At the Eocene–Oligocene boundary the first lasting ice sheet formed on Antarctica, as CO2 fell and ocean gateways opened around it.
▶ Watch it happen on the globe
Part of the Cenozoic Era & The Quaternary Ice Ages.