The Wow! signal is one of the great astronomy puzzles of the past 50 years, but it's not so mysterious in the sci-fi universe of "3 Body Problem."
Netflix's new eight-episode alien invasion saga "3 Body Problem" uses the famous SETI (search for extraterrestrial intelligence) signal as a prominent plot device in its wild centuries-spanning narrative.
The Wow! signal was an intense narrowband radio signal detected on the night of Aug. 15, 1977 by Ohio State University's Big Ear Radio Observatory and the North American Astrophysical Observatory (NAAPO) during a standard SETI search. No personnel were on duty at the time, yet the strong 72-second-long signal was recorded by a computer printer.
Related: The search for alien life
It's so named for the exclamatory word boldly written in red on the computer printout sheet by its discoverer days later, astronomer Jerry Ehman, and remains perhaps the most promising SETI candidate ever received of a potential radio transmission from an extraterrestrial species.
After 47 years and decades of dissection by researchers, the most recent work suggests that the Wow! signal might have come from the vicinity of a sun-like star situated 1,800 light-years away in the constellation Sagittarius. It's also been speculated that the signal came from a hydrogen cloud accompanying one of two comets, 266P/Christensen and P/2008 Y2 (Gibbs), which were passing through that exact section of the sky in 1977 when the Wow! signal was noticed.
"3 Body Problem," which drops on March 21, puts its own spin on the signal. In the series, Wow! is a real message from intelligent aliens beyond Earth. A Chinese astrophysicist responds to the translated signal by inviting the aliens to visit Earth — to humanity's detriment, as we later learn.
In "3 Body Problem," the communication is revealed to have been authenticated by other radio telescope installations around the globe, yet covered up as a false alarm unique to the Ohio State telescope.
But back to the real world: In 1977, the Big Ear was searching for any messages located at the electromagnetic frequency band of 1420.4056 megahertz, which is produced by the element hydrogen.
"Since hydrogen is the most abundant element in the universe, there is good logic in guessing that an intelligent civilization within our Milky Way galaxy desirous of attracting attention to itself might broadcast a strong narrowband beacon signal at or near the frequency of the neutral hydrogen line," Ehman explained in a 30th anniversary report about the Wow! signal.
Whether the Wow! signal was the result of a broadcast from an alien civilization or simply a one-time natural cosmic event has never been determined. Multiple attempts to find it, or something like it, in the same patch of sky have come up empty over the decades.
So the enigmatic phenomenon adds an interesting layer to "3 Body Problem," introducing a new generation to the SETI mystery.
"3 Body Problem" comes from "Game of Thrones" creators David Benioff and D.B. Weiss, along with "True Blood's" Alexander Woo." It's an adaptation of the first book in the "Remembrance of Earth's Past" novel trilogy by bestselling author Cixin Liu.
