Scientists say they’ve found yet another planet capable of supporting life. This brings the grand total to three: Earth, Gliese 581 d, and this newly discovered HD 85512 b. I’m still not sure why we don’t give planets simpler names. Maybe we’re waiting to ask their inhabitants what they call them.
Anyway, these planets are special because they reside in their parent stars’ Goldilocks Zones, the region that’s not too hot and not too cold. For a planet to sustain life-as-we-know-it, it must have a temperature just right for liquid water to flow on the surface.
HD 85512 b is bigger than Earth and probably a bit warmer, but I’m sure the HD 85512 b-ians don’t mind… just as the Gliese 581 d-ians don’t mind the cold.
The quest for life-bearing planets continues, but we also have to consider the possibility of alternative forms of life. Recent studies suggest arsenic-based and chlorine-based life are possible, and researchers in Scotland are trying to create inorganic life (life with no carbon whatsoever).
Silicon-based life, like the Horta from Star Trek or the creatures from the Aliens movies, still seems unlikely for lots of reasons, but scientists should remain open to that possibility too.
To the best of my knowledge, life based on arsenic, chlorine, and silicon still require liquid water, just like we do (our biochemistry is based on carbon in combination with hydrogen, nitrogen, oxygen, phosphorus, and sulfur). So these two planets are still special. But today we know of thousands of planets. By focusing on only two, we could overlook life-as-we-don’t-know-it.