What’s the coldest Earth has ever been?

Our planet’s history includes episodes of cold so extreme that glaciers reached sea level in equatorial regions. Source: https://earthsky.org/earth/whats-coldest-earth-has-ever-been…

New evidence for multiple ice ages on Mars

Earth has had at least 5 major ice ages. Now it appears Mars – the next planet outward from the sun – has undergone anywhere from half a dozen to 20 ice ages in the past several hundred million years. Source: https://earthsky.org/space/new-evidence-for-multiple-ice-ages-on-mars…

A Plunge In Incoming Sunlight May Have Triggered ‘Snowball Earths’

Jennifer Chu writes via Phys.Org: At least twice in Earth’s history, nearly the entire planet was encased in a sheet of snow and ice. These dramatic “Snowball Earth” events occurred in quick succession, somewhere around 700 million years ago, and evidence suggests that the consecutive global ice ages set the stage for the subsequent explosion of complex, multicellular life on Earth….

Ancient Mass Extinction Tied To Ozone Loss, Warming Climate

Iwastheone shares a report from Science Magazine: The end of the Devonian period, 359 million years ago, was an eventful time: Fish were inching out of the ocean, and fernlike forests were advancing on land. The world was recovering from a mass extinction 12 million years earlier, but the climate was still chaotic, swinging between hothouse conditions and freezes so deep…