SETI stands for the Seek for Extra-Terrestrial Intelligence. Kindly note that the word ‘radio’ seems nowhere in that phrase, but searching for synthetic radio transmissions from extraterrestrial civilizations seems to be close to synonymous with SETI, as strengthened via the favored film “Contact” (based mostly on Carl Kruse SETI Profile Sagan’s novel). Now there’s nothing unsuitable with radio SETI. The search for radio waves has been well thought out and would appear to offer up the utmost chance for success. However, there are more methods to skin the SETI cat (as it have been), and after forty nine years of searching primarily via radio, I recommend that some more ways be adopted and explored. Any part of the electromagnetic (EM) spectrum is suitable and up for investigation, reminiscent of optical SETI (on the lookout for laser beams) or infrared SETI (searching for Dyson Spheres) or just on the lookout for alien artifacts (as within the novel/film “2001: A Space Odyssey”). From that, we note that one can method the examine of UFOs and/or historic astronauts as representing a form of SETI. Whatever investigation tells you that extraterrestrial intelligence (ETI) exists, or as soon as existed, or would not exist in any respect (and a negative result is as important as a positive one) is SETI.
Why do SETI in any respect? That is an obvious first question. Luckily, there are lots of 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 better determine our place in the cosmos. A negative reply is just as vital as a positive answer in figuring out whether humanity is exclusive, prime of the heap, one of many nice unwashed cosmic crowd, or the new boy on the block. SETI has a practical side too in determining the existence of potential neighbors which could possibly be sources of benefit and/or threats to us. Obviously, a select few scientists, SETI fanatics, have long felt that SETI was, and is, price doing. Radio SETI is (as of this writing), a quite mature science now 49 years old.
Now if seven is a fortunate number, then seven times seven should be even luckier, yet, some 49 years after the primary radio SETI experiment (Project Ozma) was carried out by Dr. Frank D. Drake, there’s be no luck in detecting any signal of some other technological extraterrestrial civilization (49 years as I write this – it is even longer now). What does this suggest to us as a life type with an advanced technological civilization? Where are our ‘kin’ out there among the many stars?
Firstly, it means that radio SETI isn’t going to be fairly as easy as first envisioned. The number-crunching back in those early days suggested that ETI with a suitable detectable technology (radio emissions or slightly transmissions) would be fairly common. Even though solely a relative few of these haystack stalks have been sifted for that needle, it’s becoming clearer that form of SETI is not going to be easy; N (the number of technologically radio speaking ETI within the cosmos) isn’t going to be a particularly large number. So, some constraints on the SETI concept and logic have come residence to roost.
When it comes to the search to date, it’s clear (to me anyway) that there aren’t any Type III civilizations (able to harness the energy output of a complete galaxy) in any galaxy even remotely ‘shut’ (in cosmic phrases) to us. If there have been any Type 2 civilizations (capacity to command the energy output of a complete star) almost in our own galaxy it should have proved pretty obvious by now. There have been in fact many false alarms, but also a couple of cases that looked like a constructive signal was received. Alas, all have been one-offs and have by no means been picked up again. With out verification, these ‘wow’ signals remain enigmas, but not proof constructive of extraterrestrial intelligence (ETI).
Firstly, my rationalization as to why we haven’t detected ETI through radio-SETI forty nine years on. I consider it unlikely in the extreme that any ETI would deliberately goal our guardian star and solar system. We’re just too average. There isn’t any compelling reason to focus on Sol versus hundreds of thousands of different stars. Even if they did, what are the odds that their concentrating on us would just occur to coincide with our evolving the requited know-how to detect identical? What if we have been focused, but hundreds, possibly millions of years ago? ETI gave up the ghost and targeted elsewhere!