In a new paper, planetary scientists conclude that the Horta may be science fiction after all:
The authors have put together a very elaborate and detailed treatise on the topic—a must-read if you’re interested in ideas about extreme life. Not only do they provide a comparison of the chemical reactivity of carbon and silicon, they offer many amazing examples of how silicon is used by life on Earth and what type of silicon compounds exist in our own environment.
So what’s their verdict about whether Hortas or other silicon-based beings are possible? To make a long story short: It does not look very good. There aren’t many organic silicon compounds to begin with, and silicon-based life in water, or on an oxygen-rich planet, would be all but impossible as any free silicon would react quickly and furiously to form silicate rock. And that’s pretty much the end of the story.Dirk Schulze-Makuch, “Silicon-Based Life, That Staple of Science Fiction, May Not Be Likely After All” at Air & Space
Unless the planet had lots of sulfuric acid, but then…
Paper. (open access)