Stephen Hawking's first-ever Reddit AMA now accepting questions

Snotbot: It's whale research with a funny name

DiCaprio's gala for the environment raises over $40M

Pharrell's 'Freedom' video will make you think

George Clooney launches Sentry project to follow the money from Africa's wars

John Oliver gets serious about food waste

Nick Offerman grows pizzas for school lunches

Survivor-thriller 'The Revenant' offers this year's most powerful trailer

Brad Pitt tells Costco to end cruel conditions for chickens

What is ring avulsion?

Leonardo DiCaprio hands out millions to environmental groups

J.K. Rowling defends Serena Williams against body-shamers