Look! Up In The Sky! It's SUPER-EARTH!

The current top story in the Astrobiology Web 'zine is on the prospects for life on massive Earthlike planets. At least one astronomer, Dimitar Sasselov, thinks the odds are good that supermassive terrestrial bodies (which the article calls "super-Earths") could give rise to living things. He speculates that Earth may actually be on the small end of the range of habitable worlds, and wonders if this might explain the lack of evidence for other civilizations in the Galaxy. Basically, we're a lucky fluke and came early.

This starts my science-fiction brain working in two directions. The first is to speculate about what kind of stories one can set in Dr. Sasselov's universe. Millions of years hence the first inhabitants of supermassive Earthlike worlds cast their eyes to the heavens -- and find evidence of an incredibly old and advanced civilization descended from humans (and our machines). In that setting, humans are the "wise old skinny buttock-headed aliens" giving cryptic and unhelpful advice to burly, venturesome "young races" from planets with high gravity and deep oceans.

The second is to consider what an uncommon view Dr. Sasselov's speculations represent. One abiding principle in science, especially in the search for intelligent life, is the principle of Mediocrity -- the idea that there isn't anything special about us or our world, and that we are average, normal, run-of-the-mill intelligent organisms. Sasselov's idea is that we're not. We're the freaky outliers. It's a hard idea to test, until we either meet intelligent beings or establish they don't exist. But it does suggest an interesting avenue of research, which I offer to any grad student looking for a topic in astrobiology. Has anyone tried to work out, from first principles, what kind of planet would be the optimum to give rise to life? And, based on that, tried to find worlds like that to see if they show signs of intelligent inhabitants? If anyone knows of any research on that I'd love to hear about it.