It’s a derivative of Murphy’s Law that just when you say something cannot happen, it will happen. So I was excited today (September 15, 2015) when I saw that Michael Garrett, general director of the Dutch astronomy research foundation ASTRON, had released a statement saying in no uncertain terms that:
… Advanced civilizations are very rare or entirely absent from the local universe.
Garrett pointed out that sensitive new telescopes now permit astronomers to detect waste heat expected to be a signature of a certain kind of advanced alien civilization known as a Kardashev Type III civilization. Such advanced alien beings – on an exoplanet(s) in our galaxy or a nearby galaxy – would be capable of harnessing enormous energies on the scale of the galaxies themselves. Garrett has used radio observations of candidate galaxies, and he now says he has shown that there is no sign of such advanced civilizations. His results will be presented this week as a letter in the European journal Astronomy & Astrophysics. His statement said:
Advanced civilizations harnessing energies on galactic scales (so-called Kardashev Type III civilizations) are expected to be detectable in the mid-infrared part of the spectrum via the emission of significant waste heat products.
A team of astronomers led by Dr. Jason Wright (Penn State University) has already drawn up a list of several hundred candidate galaxies (culled from a total population of 100,000 objects) where unusually extreme mid-IR emission is observed.
One problem is that although rare, this kind of emission can also be generated by natural astrophysical processes related to thermal emission from warm dust.) has used radio measurements of the very best candidate galaxies and discovered that the vast majority of these systems present emission that is best explained by natural astrophysical processes.
Garrett explains his own contribution to the research as follows:
… The original research at Penn State has already told us that such systems are very rare but the new analysis suggests that this is probably an understatement, and that advanced Kardashev Type III civilizations basically don’t exist in the local universe. In my view, it means we can all sleep safely in our beds tonight – an alien invasion doesn’t seem at all likely!
Garrett says he is still looking at a few candidate galaxies:
Some of these systems definitely demand further investigation but those already studied in detail turn out to have a natural astrophysical explanation too. It’s very likely that the remaining systems also fall into this category but of course it’s worth checking just in case!
Why would I find it exciting if Professor Garrett were wrong, and if – within our lifetimes – we learned for certain that advanced alien civilizations do exist?
It’s because I’m an optimist and believe any advanced alien civilizations would have, necessarily, conquered their own basest warlike instincts and would not be interested in conquering us.
After all, if they could harness the energy of entire galaxy … why would they want Earth?
Garrett’s announcement comes more or less on the heels of a major boost to the Search for Extraterrestrial Intelligence (SETI) this past July, when Russian high-tech billionaire Yuri Milner and a stellar team of scientists and others announced an unprecedented $100 million new SETI effort. The new effort is called Breakthrough Listen, and it has astrophysical purposes, as well as the purpose of listening in on aliens. The U.S. National Radio Astronomy Observatory Green Bank Telescope, which will join the effort, called it:
… the most powerful, comprehensive, and intensive scientific search ever for signs of intelligent life in the universe. The international endeavor … will scan the nearest million stars in our own galaxy and stars in 100 other galaxies for the telltale radio signature of an advanced civilization.
So we see astronomers facing off over the question of advanced civilizations in the local universe, and that, to me, is lots of fun. Time will tell what, if anything, the Breakthrough Listen group discovers, but it’s always possible their search, too, will come to nothing, and that they will announce in 10 years or 15 years, as Michael Garrett has this week, that, among nearby galaxies in our vast universe at least, advanced civilizations are very rare or entirely absent.
If so, and I can only hope I’m around to see it happen, will the derivative of Murphy’s Law kick in, and will some alien civilization at last reveal itself?
After all, what do we know of the energy-generating techniques of advanced alien civilizations? Kardashev civilizations are interesting, and the best minds on Earth have carried ideas about them very far, but, in the end, these are all only speculations, which might be entirely off the mark.
What do you think? Tell us in the comments below.
Bottom line: On September 15, 2015, Michael Garrett, general director of the Dutch astronomy research foundation ASTRON released a statement saying in no uncertain terms that advanced civilizations are very rare or entirely absent from the local universe.
Deborah Byrd created the EarthSky radio series in 1991 and EarthSky.org in 1994. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. "Being an EarthSky editor is like hosting a big global party for cool nature-lovers," she says.