Gazing up at the night sky is simultaneously humbling and utterly thrilling. We hear from TED speakers who share an infectious sense of wonder and curiosity about our place in the universe and what lies beyond our skies. Featuring Four TED Talks: 1. Brian Greene: How Did A Mistake Unlock One Of Space's Mysteries? 2. Phil Plait: How Can We Defend Earth From Asteroids? 3. Jill Tarter: Are We Alone In The Universe? 4. Brian Greene: Is Our Universe The Only Universe?