“A long time ago in a galaxy far, far away…” These words put us into other galaxies to meet advanced alien civilizations. Some of the most and least loved characters from Star Wars are aliens. They are instead intelligent life from other galaxies that somehow found other aliens in the galaxy and formed a cooperative government. I think we as humans share some of the explorer instinct that they have. I wonder what it took for them to find each other in their galaxy. In this post I’ll be writing about how we are doing with the search for intelligent life in our corner of the universe.
It’s only natural to wonder who or what else is out there, but some people make it their job to try and find the answer. What tools do they have? Astronomers at Search for Extraterrestrial Intelligence (SETI) work to discover new planets and moons and also search the skies for telltale radio signals produced by advanced civilizations. This nonprofit was started nearly 50 years ago in part by a man named Frank Drake. Drake is perhaps best known for his back-of-the-envelope equation estimating the number of intelligent civilizations (N) in our galaxy:
7starsyear*0.22planetsstar*0.001lifeformsplanet*0.10 intelligent specieslifeform*50,000 years =7.5 intelligent species
This means that I’d predict seven and a half intelligent civilizations are out there waiting for us. If you think that intelligent life is rare then the number goes down but if you think civilizations last longer the number goes up. You can look in galaxies that make more or fewer planets. Rather than producing an answer to the question, this equation tells us what to think about when searching for intelligent life.
It may be possible that we’ve already observed signs of alien life. You may have read in September about a star that is dimming in an unusual pattern. The sharp dips in brightness shows that there is a very large object between us and that star. In the paper, researchers propose several possible explanations, including planetary debris, comets, or dust, but in interviews, the researchers and other collaborators offer another explanation: alien megastructures. Jason Wright, an astronomer from Penn State University, looked at the data and said, “I was fascinated by how crazy it looked. Aliens should always be the very last hypothesis you consider, but this looked like something you would expect an alien civilization to build.” Some of these researchers teamed up with SETI to see whether this star and its dimming might also contain the radio signals indicative of intelligent life but did not see any signals. This most likely means that the dimming is just space doing space stuff, but we cannot exclude the possibility that perhaps the civilization has particular reasons for not broadcasting radio signals or that the megastructure is a relic from a fallen empire.
So the search continues. As our ability to look and journey into space increases I believe it’s only a matter of time until we find new life if it’s out there. The universe is a big place. I think it’d be pretty cool to find some neighbors. In my next segment I’ll be talking about warp drives and other ways of actually meeting these neighbors.