a molten, poison-aired rock that spent a billion years failing to kill everything, then didn't.
means the planet's first chapter, roughly 4.6 to 4 billion years ago, before oxygen, continents, or anything alive as we'd recognize it.
from geologists split earth's 4.5-billion-year history into eons, and the earliest, the hadean, is literally named after hades because the surface was a hellscape of magma oceans and asteroid bombardment.
theia impact — a mars-sized body hit earth 4.5 billion years ago, birthing the moon
late heavy bombardment — asteroid storm around 4.1 to 3.8 billion years ago scarred the moon and earth
jack hills zircons — australian crystals dated to 4.4 billion years, oldest earth material found
great oxidation event — cyanobacteria poisoned the air with oxygen starting 2.4 billion years ago