Aliens in Our Imagination: Friendly or Frightening? From the pointy ears of the Vulcans to the razor-sharp teeth of the Xenomorph, humanity has never stopped imagining what aliens might look like.

For thousands of years, humanity has looked up at the stars asking the same question. Are we alone? Then one day, it finally ...

Earth seems like a troubled place right now, but at least our cosmic surroundings appear peaceful. But this is not universally true, as explosions, collisions and other dangers lurk in other places ...

Add Yahoo as a preferred source to see more of our stories on Google. Scientists say tiny exoplanets smaller than Mars simply can't hold an atmosphere long enough for alien life to survive. ©Image ...