Doomsday Clock: Countdown to catastrophe?

The minute hand on the Doomsday Clock is a metaphor for how vulnerable the world is to catastrophe.

Amid concerns over climate change, the clock has been close to midnight for the past few years.

Now, it's moved 30 seconds closer.

Here's how the Doomsday Clock changed from 1947 up to last year.

First broadcast in January 2017