This week was hard on the conflict-averse. But if you're up on nursery rhymes, prehistoric bodily fluids and Renaissance art, you'll get at least three right this week.

The Doomsday Clock now stands at 89 seconds to midnight, the closest to catastrophe in its nearly eight-decade history. Here's a look at how — and why — it's moved.

Earth, for the second year running, is nearing apocalypse, a science-oriented advocacy group said, pointing to its famous "Doomsday Clock" that shows 90 seconds till midnight.