Study: early asteroid impacts kept Earth's surface hot and unstable
Turns out, Earth's earliest days were way more intense than we thought.
A new study shows that constant asteroid impacts over four billion years ago pumped so much heat into the planet that the surface stayed super hot and unstable for ages.
This explains why we find ancient zircon crystals from that time, even though almost no intact rocks survived.
Silica enrichment laid groundwork for continents
Those asteroids didn't just make things chaotic; they also cracked up Earth's crust and melted parts of the mantle, creating fresh magma that recycled the surface again and again.
This process helped enrich the crust with silica, laying down the groundwork for continents to eventually form.
And even with all this upheaval, there was still water on early Earth!
Once asteroid strikes slowed down around 3.9 billion years ago, things finally cooled off enough for large stretches of continent to stick around.