I have only recently returned to regular blogging, and in several recent posts I’ve alluded to the fact that I’m planning to take my Sci-Fi writing in a new creative direction. A lot of things are changing for me right now. A lot of the things I’m doing (or trying to do) are new. With that in mind, I feel like this is a good time to restate some of my views and beliefs about science and the universe, starting with my views and beliefs about extraterrestrial life.
When people ask “Do you think we’re alone in the universe?” I get slightly annoyed by that question. It’s too big a topic to reduce to a simple yes or no question. In Humanity’s search for extraterrestrial life, there are really three kinds of life we might find out there:
Microbial Life: Almost as soon as Earth existed, terrestrial microorganisms existed, too. Microbes developed so swiftly and so easily on this planet that the same thing must have happened elsewhere. For this reason, I believe extraterrestrial microorganisms are plentiful across the cosmos.
Multicellular Life: Complex multicellular organisms—fish, plants, bugs, etc—exist on Earth due to a happy accident. About 2.4 billion years ago, some of Earth’s microbes started burping up oxygen. To those microbes, oxygen was a waste product, but that waste product could also be used in biochemical reactions to create energy. Lots of energy. Enough energy to make complex multicellular life possible. If multicellular life requires this sort of happy accident in order to exist, then I suspect multicellular life must be rare across the universe.
Intelligent Life: I’m going to define intelligence as the ability of a species to make and use tools, to communicate complex ideas, and to generally improve upon its knowledge and technology over time. As far as we can tell, life like that only evolved one time on our planet. Given the vastness of the entire universe, I think intelligent life must exist elsewhere, but I also think it must be extremely rare.
Some time around 1950, nuclear physicist Enrico Fermi famously asked “Where is everybody?” in reference to alien life. As Fermi saw it, advanced alien civilizations should be out there, and their activities in space should be obvious to us. And yet when we look out into the universe, we see nothing. This apparent contradiction—aliens should be everywhere, and yet they seem to be nowhere—is today known as the Fermi Paradox.
So I guess my answer to questions like “Where is everybody?” or “Are we alone in the universe?” depends on what kind of alien life we’re talking about. If we’re talking about alien microorganisms, I think they’re plentiful, and I think it’s only a matter of time before we find evidence of alien microbes on Mars or on one of the icy moons of the outer Solar System. If we’re talking about multicellular life, that sort of life is rare. And intelligent life must be rarer still—so rare, in fact, that our nearest intelligent neighbors may be hundreds, thousands, or even millions of lightyears away.
But these are just my opinions. My opinions about this topic have changed over time, and as I keep learning, my opinions and expectations will, no doubt, change again.
So, friends, what are your opinions and expectations concerning extraterrestrial life? Do you think I’m on the right track, or is there something I’ve missed that you think I should learn more about?