SETI stands for the Seek for Extra-Terrestrial Intelligence. Kindly note that the word ‘radio’ seems nowhere in that phrase, yet searching for synthetic radio transmissions from extraterrestrial civilizations seems to be near synonymous with SETI, as bolstered via the popular movie “Contact” (based on Carl Kruse SETI Profile Sagan’s novel). Now there is nothing mistaken with radio SETI. The search for radio waves has been nicely thought out and would seem to supply up the maximum chance for success. But, there are more methods to skin the SETI cat (as it had been), and after 49 years of searching primarily through radio, I counsel that some more ways be adopted and explored. Any a part of the electromagnetic (EM) spectrum is suitable and up for investigation, reminiscent of optical SETI (looking for laser beams) or infrared SETI (searching for Dyson Spheres) or just in search of alien artifacts (as within the novel/movie “2001: A Area Odyssey”). From that, we note that one can approach the study of UFOs and/or historical astronauts as representing a form of SETI. Whatever investigation tells you that extraterrestrial intelligence (ETI) exists, or once existed, or doesn’t exist at all (and a negative result is as essential as a constructive one) is SETI.
Why do SETI in any respect? That’s an obvious first question. Thankfully, there are many good solutions to that question. There’s pure scientific curiosity for starters – exploring just for the sake of exploring. Then there’s the more philosophical strategy in that SETI helps to higher determine our place within the cosmos. A negative answer is just as important as a optimistic reply in figuring out whether or not humanity is exclusive, prime of the heap, one of many nice unwashed cosmic crowd, or the new boy on the block. SETI has a sensible side too in figuring out the existence of potential neighbors which may very well be sources of benefit and/or threats to us. Clearly, a select few scientists, SETI fans, have long felt that SETI was, and is, value doing. Radio SETI is (as of this writing), a quite mature science now forty nine years old.
Now if seven is a fortunate number, then seven occasions seven must be even luckier, but, some forty nine years after the first radio SETI experiment (Project Ozma) was performed by Dr. Frank D. Drake, there’s be no luck in detecting any sign of every other technological extraterrestrial civilization (49 years as I write this – it’s even longer now). What does this recommend to us as a life form with an advanced technological civilization? The place are our ‘kin’ out there among the stars?
Firstly, it means that radio SETI is not going to be quite as straightforward as first envisioned. The number-crunching back in those early days advised that ETI with a suitable detectable expertise (radio emissions or fairly transmissions) would be pretty common. Despite the fact that solely a relative few of those haystack stalks have been sifted for that needle, it is becoming clearer that form of SETI isn’t going to be easy; N (the number of technologically radio communicating ETI in the cosmos) is not going to be an especially massive number. So, some constraints on the SETI concept and logic have come home to roost.
By way of the search up to now, it’s clear (to me anyway) that there aren’t any Type III civilizations (able to harness the energy output of an entire galaxy) in any galaxy even remotely ‘shut’ (in cosmic phrases) to us. If there were any Type 2 civilizations (ability to command the energy output of an entire star) almost in our own galaxy it ought to have proved pretty apparent by now. There have been of course many false alarms, but in addition a few cases that regarded like a constructive signal was received. Alas, all have been one-offs and have never been picked up again. Without verification, those ‘wow’ signals stay enigmas, however not proof optimistic of extraterrestrial intelligence (ETI).
Firstly, my explanation as to why we haven’t detected ETI through radio-SETI 49 years on. I consider it unlikely within the excessive that any ETI would deliberately target our mum or dad star and solar system. We’re just too average. There’s no compelling reason to focus on Sol versus hundreds of 1000’s of other stars. Even if they did, what are the chances that their focusing on us would just happen to coincide with our evolving the requited expertise to detect identical? What if we had been focused, however thousands, perhaps thousands and thousands of years ago? ETI gave up the ghost and targeted elsewhere!