A Look in the Rearview Mirror at the Famed Wow! Signal
Are you aware of any of the mysteries that have lingered for decades, and have excited scientists and dreamers alike? Let’s take a look today at another of the most fascinating cosmic enigmas—the Wow! Signal. It is a short-lived radio flash that has caused great excitement about extraterrestrial intelligence and speculation since 1977, when it was first discovered. So pour yourself a cup of coffee, and let’s examine why this “Wow!” moment in astronomy has fascinated people for such a long time.
The Signal That Caused People to Say "Wow!"
On August 15, 1977, Jerry R. Ehman, a volunteer with the Ohio State University’s Big Ear radio telescope, saw a strong narrowband radio signal emanating from the constellation Sagittarius. What made it so unique? Although the signal existed for only 72 seconds, the signal was so unique and unlike any other cosmic noise that Ehman wrote “Wow!” next to it on the printout of the data—thus creating the name for the signal.
Why was it so significant? Most cosmic noise exists randomly or across a wide band of frequencies, but this signal was very narrowly focused at 1420 MHz, the hydrogen line—a frequency that astronomers believe will be the first place to find signals from intelligent life. It seemed as though someone turned on a beacon, although only for a short period of time.
Possible Sources for the Signal
In the years since, there have been numerous ideas about the source of the signal. Many believe that it may have come from a transmission by an alien civilization that was attempting to attract our attention, while others believe that it may have originated from a natural phenomenon of the Earth, such as a passing satellite, a reflection of natural sources, or possibly unusual atmospheric conditions. Despite numerous searches conducted with various radio telescopes around the world, researchers have never detected the Wow! Signal again.
The fact that the signal has not been detected again has only contributed to its mystique. Is it possible that the signal was a single cosmic “hello”? Is it a glitch in our equipment? Or perhaps it could be something entirely different that we do not understand. To many, it represents a tantalizing clue that we are not alone in the universe. To others, it reminds them of the vastness and mystery of space.
Why the "Wow!" Signal Remains Significant Today
Although the Wow! Signal itself is no longer a puzzle, it represents humanity’s curiosity and willingness to listen out into the unknown. The Wow! Signal helped to establish the Search for Extraterrestrial Intelligence (SETI) initiatives, which continue to use increasingly sophisticated technology to scan the skies. The Wow! Signal also generates discussions regarding the interpretation of ambiguous evidence and the importance of persistence in scientific inquiry.
If you would like to learn more about the Wow! Signal’s legacy, I would suggest viewing a documentary or listening to a podcast that examines the legacy of the Wow! Signal—each of which presents new perspectives and occasionally new theories. If you look up at the stars tonight, it can be fascinating to think that somewhere beyond those twinkling stars lies a mystery waiting for us to discover.
Conclusion
The Wow! Signal represents one of the most tantalizing puzzles in the search for extraterrestrial intelligence—a short-lived, bright moment of time that was recorded by accident and continues to ask the question: are we truly alone? Regardless of the answer, the story of the Wow! Signal is a reminder to us all to keep looking up, to continue to wonder, and to dream about the vast cosmos that we call home.
Next week, we will discuss some recent developments in the discovery of exoplanets—new planets that may eventually expand our cosmic neighborhood. Until then, maintain your sense of wonder and feel free to express your thoughts or theories regarding the Wow! Signal. Every major discovery begins with a question.