The Search For Extraterrestrial Radio Signals – We May Already Have Discovered Evidence for Intelligent Life in the Form of “Wow Signals”
My favorite quote from, “Communication With Extraterrestrial Intelligence”: “Interesting signals without persistence are observed thousands of times each day at the SETI Institute.”
“Signals without persistence” refers to an unknown radio signal believed to be from the sky intercepted on a certain frequency that is observed for a few seconds or minutes only, and then ceases, never to be heard from again.
Some Thoughts Inspired By the New Book, “Communication With Extraterrestrial Intelligence”, Edited by Douglas A. Vakoch, SUNY Press, NY
By James Bean
Below I raise the question: what if we’re living in a galaxy where short, random “wow” signals are the norm, not long transmissions from ET “beacons” as imagined in the movie Contact?
Being a long term shortwave radio hobbyist, over the years I’ve noticed many mystery signals. Some of those pertain to over-the-horizon radar, spread spectrum communications, no doubt military, or air traffic, also “numbers stations”. There are deliberate signals being bounced off of various layers of the ionosphere, perhaps to determine what frequencies might be best for communications at various times of the day and night. Shortwave propagation is an ever-changing thing, even effected by weather and solar activity. Some of these technologies move up and down the dial using many different frequencies simultaneously, or are rapidly going from one frequency to the next. I’ve followed signals before that literally sweep past many frequencies: 3 something MHz, 4, MHz, 5 MHz, and so on.
It would be rather surprising if it turns out the “cosmic” or “galactic radio dial” is devoid of activities going on for the purpose of scientific exploration. And that ET activity, if it exists, might to us seem like unpredictable, random signals lasting for a few seconds only. I suppose we would have to have a much more sophisticated, elaborate ability to simultaneously scan all frequencies at once in order to notice discernible patterns, such as a mystery radio signal sweeping across many frequencies, suggesting intelligent life or automated electronics at work “somewhere out there.”
Thus far, what leaps out at me from reading, Communication With Extraterrestrial Intelligence, are these descriptions of multiple “wow”** or mystery signals and pulses.* And this leads me to make proposals about creating new techniques, attempting to find a way to make repeatable observations, addressing the difficult issue of random “signals without persistence.”
Add to the Drake Equation: the percentage of advanced extra terrestrial civilizations with technology that, oddly enough, seek to make themselves known to a species such as ourselves! It seems quite reasonable that the overall number of advanced civilizations in the galaxy in possession of advanced technology would be a far larger population than the number of advanced extraterrestrial civilizations with technology that have a desire to be “celestial missionaries”, setting up beacons, deliberately sending out continuous signals for us to notice. In other words, the reality may very well be, it’s more likely we have the potential to intercept “wow” type signals or short mystery pulses rather than continuous signals (like imagined in the movie Contact). Perhaps we’re living in a galaxy where “wow” or accidental leakage type signals from ET’s are much more likely for us to find than deliberate beacons.
There are many scientific reasons why ETs could have antenna arrays belching out massive quantities of RF, and we might notice this activity occasionally, in what to us, with our limited ability to observe a few frequencies only, could seem like short increments of 10 to 70 second bursts. If most ET’s are NOT trying to broadcast to us, maybe they are communicating amongst themselves, perhaps have some equivalent of radar, are keeping a watchful eye on valued solar systems (“cosmic burglar alarms”, if you will), or scientific exploration, probing regions of the galaxy with various types of signals and technologies.
I find these potential mystery signals mentioned in the book to be quite intriguing! Many no doubt are glitches or false-positives, but the possibility or even likelihood of real ET signals arriving in the form of shorts bursts of accidental leakage not intended for us, seems more plausible than any other scenario. For me, this possibility rings true.
That such signals would be next to impossible to verify and therefore not be, at present, appreciated by humans as historic events, is understandable, and predictable. But all it takes is evidence of one signal to be extraterrestrial and extra solar in origin, or at least quite suspicious, and that’s big news. SETI would have it’s funding as never before, to say the least!
The Thorny Issue of Short Random Signals
I wonder if it can be possible to detect any discernible patterns with these short, random signals? Might they be emanating equally from all parts of the sky? Could a noteworthy percentage of them be coming from a certain direction or region?
Right now, if SETI is based on the premise of there being an ET beacon sending out a continuous signal, does this mean that there’s no effort to record 10-90 second random signals? We would need to detect activity, then and only then would other antennas and receivers be fired up to go and examine the contents of such signals….to actually go and listen to the audio, check it for video, digital “ones” and “zeros” or other signs of technology and intelligence? In other words, at present with SETI, the “phone” would have being “ringing” for a few hours before anyone could pick up and hear the voice of the one who’s calling? No “answering machine” for them to leave a message after the “beep” that we could examine later on?
If detected, a signal, would have to continue being received for hours in order for multiple telescopes to establish that this signal is — or is not — broadcasting from a certain location in the sky, maybe from a distant solar system, but being able to capture a signal, and examine it in detail, would be useful, especially if 30 seconds might be “it”, the only opportunity we might get.
Could a narrow-frequency “wow” type signal consist of a blank or silent carrier? Based on current methods used by the SETI Program, could we tell if it’s modulated? What properties would it have exactly? What is the quality of the information currently being stored about the various frequencies being monitored, even for short periods of time? I know nothing of operational details, but it seems to me as a complete outsider to SETI, that what a signal consists of would reveal much, even if that signal was only 10 or 70 seconds in length: a garage door opener, satellite telemetry, a old Rolling Stones hit from the 70’s, or a highly unusual signal packed with a complicated stream of data that seems like nothing on Earth? With the SETI Program, I wonder if there is a digital equivalent of hitting the “rewind button” to have a listen to any unusual signals that have been detected in the past but are only active for 70 seconds or less? How to separate “wheat” signals from “chaff” signals? Can software be designed to automatically turn on extra equipment to capture more information during possible “wow signal” events?
*”Interesting signals without persistence are observed thousands of times each day at the SETI Institute. Figure 4.3 for example shows a result obtained in a narrow band SETI search near the PiHI Frequency (the number phi times the HI observing line of 1420.4 MHz). This (extremely powerful) ~10 second pulse of narrow band radiation appeared in one fifty second observation period but was never re-observed. This pulse has interesting features: it is observed at a magic frequency in the direction of a nearby and potentially habitable star. Yet we cannot be sure this signal was created intentionally or unintentionally by some transmitter on Earth. Hence, after multiple observations over two weeks and no re-detection, we gave up (although this direction is added to a catalog of directions to re-observe as time permits).” (from pages 52 and 53, “Communication With Extraterrestrial Intelligence”, Edited by Douglas A. Vakoch, SUNY Press, NY)
*The book also refers to mystery or “wow” signals on pages: 38, 43, 110, also optical SETI mystery pulses on 140, including the “Is it ET signal?”
Interstellar Signal from the 70s Continues to Puzzle Researchers, by Seth Shostak – Senior Astronomer, SETI Institute:
**Youtube Video on the original and famous “Wow Signal” of the 1970’s:
The Search For Other Earths, Part 1 – Spiritual Awakening Radio Podcast:
The Search For Other Earths, Part 2 – Spiritual Awakening Radio Podcast: