Astrobiology (general): March 2021

In Kevin Hand's "Alien Oceans: The Search For Life In The Depths Of Space" we learn that Earth is just one example of a myriad ways that a world can have an ocean. And searching for life on other ocean worlds requires a combination of old tools and new approaches to using those tools.

We live on an ocean world with 71% its surface covered by a water. For all of history humans had an intrinsic bias that all inhabited worlds would have large oceans - since we do. Indeed, the large flat plains of our Moon still bear names of imaginary seas based on that bias and early telescopes. That said we held to the notion that life would arise on a world if only it had Earth's basic characteristics - one of which was large bodies of water. Well, we now know that there is more than one way to have a planet with lots of liquid water.