Enceladus – NASA
When it comes to looking for alien life, scientists mostly focus on where there is water. Now researchers suggest that looking at “bioessential” elements such as phosphorus and molybdenum could help judge a world’s potential for life.
There is life virtually wherever there is water on Earth, from clouds high above the surface to the deepest layer of Earth’s crust. As such, the search for life outside Earth typically concentrates on worlds that are “habitable,” possessing temperatures conducive to hosting liquid water on its surface.
For example, although the surface of Venus is currently hot enough to melt lead, a 2016 study suggested it may have been habitable until as recently as 715 million years ago. Scientists have even conjectured that if life once existed on Venus, it still might survive within its clouds.