Type: Video

Could We Destroy the Earth?

There are a lot of nuclear weapons on Earth, so many that we often say it’s enough to “destroy the world several times over.” But could we?

How Memories Form And How We Lose Them

Think back to a really vivid memory. Got it? Now try to remember what you had for lunch three weeks ago. That second memory probably isn’t as strong—but why not? Why do we remember...