Do you believe in extra-terrestrial life? Best of Earth Lab: http://bit.ly/EarthLabOriginals Best of BBC Earth: http://bit.ly/TheBestOfBBCEarthVideos Are These Signals From Aliens? Exploring alien signals, elusive dark energy, and the likelihood of finding another ‘you’ out there. Over ...

Before she left NASA, former NASA Chief Scientist Ellen Stofan sat down with us and explained why NASA has no protocol for dealing with intelligent extra-terrestrial life — even if they came knocking on our doorstep tomorrow. Science Insider tells you all you need to know about science: space, ...