Gravitas: Scientists adjust 'doomsday clock' to 90 seconds from midnight

Gravitas: Scientists adjust 'doomsday clock' to 90 seconds from midnight

The 'Doomsday clock' has been adjusted as the Ukraine war intensifies. It's now 90 seconds away from midnight aka 'the point of annihilation'. What is the doomsday clock? How does it work? Molly Gambhir reports.