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 close to synonymous with SETI, as reinforced by way of the favored movie “Contact” (based mostly on Carl Kruse SETI Profile Sagan’s novel). Now there is nothing improper with radio SETI. The seek for radio waves has been effectively thought out and would seem to offer up the utmost probability for success. But, there are more ways to skin the SETI cat (as it had been), and after 49 years of searching primarily by way of radio, I recommend that some more methods be adopted and explored. Any part of the electromagnetic (EM) spectrum is suitable and up for investigation, akin to optical SETI (on the lookout for laser beams) or infrared SETI (searching for Dyson Spheres) or just looking for alien artifacts (as within the novel/film “2001: A Space Odyssey”). From that, we note that one can strategy the examine of UFOs and/or historic astronauts as representing a type of SETI. No matter investigation tells you that extraterrestrial intelligence (ETI) exists, or as soon as existed, or does not exist at all (and a negative result’s as vital as a constructive one) is SETI.
Why do SETI at all? That is an obvious first question. Fortunately, 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 answer is just as essential as a constructive answer in figuring out whether humanity is unique, high of the heap, one of the nice unwashed cosmic crowd, or the new boy on the block. SETI has a sensible side too in determining the existence of potential neighbors which may very well be sources of benefit and/or threats to us. Clearly, a select few scientists, SETI lovers, have lengthy felt that SETI was, and is, value doing. Radio SETI is (as of this writing), a fairly mature science now 49 years old.
Now if seven is a fortunate number, then seven occasions seven should be even luckier, yet, some 49 years after the first radio SETI experiment (Project Ozma) was conducted by Dr. Frank D. Drake, there’s be no luck in detecting any signal of every other technological extraterrestrial civilization (49 years as I write this – it is even longer now). What does this recommend to us as a life kind with an developed technological civilization? The place are our ‘kin’ on the market among the stars?
Firstly, it suggests that radio SETI isn’t going to be quite as easy as first envisioned. The number-crunching back in these early days urged that ETI with a suitable detectable expertise (radio emissions or quite transmissions) can be fairly common. Even though solely a relative few of those haystack stalks have been sifted for that needle, it’s changing into clearer that form of SETI is not going to be simple; N (the number of technologically radio speaking ETI within the cosmos) is not going to be a particularly giant number. So, some constraints on the SETI concept and logic have come residence to roost.
By way of the search to this point, it is clear (to me anyway) that there are not any Type III civilizations (able to harness the energy output of a complete galaxy) in any galaxy even remotely ‘close’ (in cosmic phrases) to us. If there were any Type 2 civilizations (ability to command the energy output of a whole star) almost in our personal galaxy it should have proved pretty obvious by now. There have been of course many false alarms, but also a number of cases that regarded like a constructive signal was received. Alas, all have been one-offs and have by no means been picked up again. With out verification, those ‘wow’ signals remain enigmas, however not proof constructive of extraterrestrial intelligence (ETI).
Firstly, my explanation as to why we haven’t detected ETI via radio-SETI 49 years on. I consider it unlikely in the excessive that any ETI would deliberately target our dad or mum star and solar system. We’re just too average. There isn’t any compelling reason to focus on Sol versus hundreds of thousands of other stars. Even if they did, what are the percentages that their concentrating on us would just occur to coincide with our evolving the requited expertise to detect identical? What if we have been targeted, however 1000’s, possibly thousands and thousands of years ago? ETI gave up the ghost and focused elsewhere!