Scientists have known for some time that Earth’s atmosphere loses several hundred tons of oxygen each day. They understand how this oxygen loss happens on Earth’s night side, but they’re not sure how it happens on the day side. They do know one thing though; it happens during auroras.
When people talk about what killed the dinosaurs, they usually talk about asteroids. Scientists generally agree that was the trigger for one huge extinction, but there have been many more mass die-offs in Earth’s history with many more causes. One extinction event that’s more recent — both in its timescale and in its discovery — happened about 2.6 million years ago, killing off large numbers of ocean animals and ending what’s known as the Pliocene epoch. How did it happen? New research is suggesting that an ancient supernova is to blame.