In one of his final on-camera appearances, iconic physicist Stephen Hawking issued a warning to humanity about the existential threats we face and how our survival depends on colonizing another planet. From the Series: Leaving Earth: Or How to Colonize a Planet source
Tag: Asteroid
Where did Earth’s water come from? – Zachary Metz
View full lesson: Water covers over 70% of the Earth, cycling from the oceans and rivers to the clouds and back again. It even makes up about 60% of our bodies. But in the rest of the solar system, liquid water is almost impossible to find. So how did our planet end up with so […]