"All these possibilities are out there. And we live in the one that is hospital to our form of life." — Brian Greene James Duncan Davidson/TED hide caption

itoggle caption James Duncan Davidson/TED

"We should search because it tells us how to collaborate our place in the cosmos." — Jill Tarter TED / James Duncan Davidson hide caption

itoggle caption TED / James Duncan Davidson

Nobel Prize winner Saul Perlmutter explains part of his research in astrophysics. Kimberly White/Getty Images hide caption

itoggle caption Kimberly White/Getty Images