How would humanity change if we knew aliens existed?

We have yet to discover any signs of an extraterrestrial civilization — a prospect that could quite literally change overnight. Should that happen, our sense of ourselves and our place in the cosmos would forever be shaken. It could even change the course of human history. Or would it? » 2/14/14 8:10am 2/14/14 8:10am

Could we detect signs of alien life on a dying planet?

Scientists say that we should be on the lookout for purple planets, a possible sign of primordial extraterrestrial life. But what about the biosignatures of exoplanets that are dying? A recent study concluded that it is indeed possible — we just have to recognize the signs. » 11/25/13 1:20pm 11/25/13 1:20pm

Why scientists need to search for alien life on purple planets

Billions of years ago, when microbial life first emerged on Earth, our planet would have appeared purple from space. Armed with this knowledge, scientists now say we should be on the lookout for exoplanets tinged in a similar purple hue — a possible sign of extraterrestrial life. » 11/13/13 7:20am 11/13/13 7:20am

Everything you need to know about NASA's "completely new form of life"

NASA scientists have just announced the discovery of life fundamentally different from anything else we've ever seen before. Here's what this discovery means for our understanding of biology, the search for extraterrestrial life, and even how this could revolutionize bioenergy. » 12/02/10 1:39pm 12/02/10 1:39pm