Exobiology: SETI: The Search for Extraterrestrial Intelligence

Exobiology was the original term given to the sciences central to the question of life-in-the-Universe. It’s now been largely replaced by Astrobiology, but I’ll stick with the original. The most interesting form of life-in-the-Universe is going to be extraterrestrial intelligence, ideally at a technological level to be able to communicate with us. We now have the technological ability to search for our equals or better that might inhabit abodes somewhere out there, and have been doing so since the early 1960’s. That search goes by the term of SETI – the Search for ExtraTerrestrial Intelligence. 

SETI has been a lengthy experiment in trying to detect our intellectual extraterrestrial equals or better somewhere out there by detecting their electromagnetic radio (sometimes optical or infrared) transmissions, whether that be just leakage (like our radio and TV broadcasts) or a deliberate signal.  Five decades on, the quarry remains elusive. My advice to SETI scientists is not to put all your SETI eggs in the electromagnetic (EM) basket.

SETI stands for the Search for Extra-Terrestrial Intelligence. Kindly note that the word ‘radio’ appears nowhere in that phrase, yet searching for artificial radio transmissions from extraterrestrial civilizations seems to be near synonymous with SETI. Now there is nothing wrong with radio SETI. The search for radio waves has been well thought out and would appear to offer up the maximum chance for success.  But, there are more ways to skin the SETI cat (as it were). Any part of the EM spectrum is suitable and up for investigation, such as optical SETI (looking for laser beams) or infrared SETI (searching for Dyson Spheres) or just looking for alien artefacts. From that, we note that one can approach the study of UFOs and/or ancient astronauts as representing a SETI. Whatever investigation tells you that ETI exists, or once existed, or doesn’t exist at all (and a negative result is as important as a positive one) is SETI.

It is said that the optimist is frequently, in fact usually disappointed while the pessimist frequently or usually isn’t. So is SETI a suitable research venue or course of inquiry for the optimist or the pessimist? I suggest here that to do SETI you need to be the eternal optimist, while realistically, SETI is for pessimists! Traditional SETI searches for EM  photons, traditionally radio, increasingly optical and intra-red (IR), emitted by an ET technology, to date, has resulted in, well, no ET. Maybe there is no ETI, or maybe there’s ETI but little in the way of their manufactured photons.

In terms of the search to date, it’s clear (to me anyway) that there are no Type III civilizations (able to harness the energy output of an entire galaxy) in any galaxy even remotely ‘close’ (in cosmic terms) to us. If there were any Type II civilizations (ability to command the energy output of an entire star) nearby in our own galaxy it should have proved pretty obvious by now. There have been of course many false alarms, but also a few what looked like positive signals received. Alas, all have been one-offs and have never been picked up again. Without verification, those ‘wow’ signals remain enigmas, but not proof positive of ETI.

I wish to make it clear that I totally support EM SETI to the hilt. It is bona fide science. Nothing ventured, nothing gained is applicable here. It’s just that EM SETI isn’t the only game in town, and I equally support and encourage any and all other search strategies. The exception is that if one wants to look for signs of ETI in other galaxies than our own, then EM SETI is just about the only game in town.

What SETI is the best SETI? It used to be radio telescopes tuned to the 21 cm frequency of neutral hydrogen (H). Then it became the ‘water hole’, that band of frequencies between neutral hydrogen and the hydroxyl (OH) radical: H + OH = the water molecule, hence the ‘water hole’ (a terrestrial place where many different species gather together for a common purpose). Since then, lots of exobiology/SETI scientists have proposed lots of other possible radio frequencies, such that today, SETI searches tend to be broad spectrum ones rather than focusing on just one or two frequencies, and that has extended into the optical and infra-red range as well.   

So, what SETI is the best SETI? Well, SETI has to be affordable and practicable. Expensive and exotic technologies probably won’t attract many research grants. To make that economic long story somewhat shorter, it got me to thinking that there’s a cheaper SETI option than current EM SETI. I refer to the mega-reams of ordinary astronomical data bits that must reside in various repositories.

Now over many decades of astronomical observations and data gathering, be it from the surface (optical and radio telescopes), balloons, satellites (in particular declassified data from military satellites), and space probes, ordinary astronomers have looked at same, written their peer-reviewed papers, and moved on to new topics of interest and observations. The interesting bit is that here we have these reams of data (and publications) by astronomers who had no interest at all in extraterrestrials (ET’s), ETI, or SETI, yet who might have, by accident, stumbled across an ETI signal without realizing it – because that wasn’t their agenda.

So, if someone with that agenda, were to comb through that already existing data (note – no need to request telescope time and associated hassles), then maybe, just maybe, there’s an ETI signal in all the pre-existing data-noise.  

Here are a few fairly low cost SETI strategies. 1) Further EM surveys of entire galaxies (billions of stars at a go) looking for an ultra advanced high technology civilization, the sort that would stand out in an entire galaxy. 2) Surveying nearby sun-like stars for electromagnetic leakage (like radar, radio, TV, etc.). It’s unlikely IMHO that we would be deliberately targeted by an optical (laser) or radio beacon, so we need to look for EM leakage. Because that would be relatively weak, the stars will have to be close, and should be similar to our Sun. 3) Intense examination of highly detailed photographs of the moon and Mars for any signs of artificiality or artefacts.  4) Examine with a fine tooth comb any existing astronomical data for anomalies suggestive of intelligence. For example, there could be anomalous spectral lines in stars, giving away the presence of atoms that shouldn’t be there but which were dumped into said star by ETI as a ways and means of attracting attention. 5) There should be a scholarly examination of terrestrial mythology, especially religious mythology, for hints of ETI. For example, do all gods in all the worlds religious mythologies live in the sky (like Heaven, or Valhalla) and possess magical (technological) powers? 6) For once, there should be a serious examination of the UFO data to determine once and for all if there is a case for some UFO events exhibiting ETI technology.