Scientists found a mysterious signal in space. Its source was closer than Australia
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Scientists spent nearly a year trying to find its source after a mysterious signal appeared to have come from our sun's closest star.
What was the result? According to two research published in Nature Astronomy this week, the signal did not come from an alien planet circling Proxima Centauri, but rather something more mundane, such as a radio, telephone, or computer located somewhere in Australia.
Sofia Sheikh, an Astronomer at the University of California Berkeley and co-author of both papers said that "it is human-made radio interference from a technology, probably on top of the Earth." NPR attempted to reach Sheikh, but was unsuccessful.
A radio telescope measuring 210 feet (64 meters) at the Parkes Observatory in New South Wales was used to detect the signal. The Dish, as it is known in Australia, was the subject for a 2000 movie starring Sam Neill.
Breakthrough Listen is the largest scientific research program ever to listen for extraterrestrial technology. The radio telescope is part Breakthrough Listen. This program was launched at Berkeley SETI Research Center at the University of California at Berkeley in 2016. It also involves radio telescopes from around the globe.
How the search moved from the stars to Earth
NPR's Jason Wright, an astronomer and astrophysics professor who is also the director of Penn State Extraterrestrial Intelligence Center tells NPR that "this was a really pernicious sign."
The signal lasted approximately five hours at 982 megahertz. This frequency is normally reserved for aircraft communications. Researchers eliminated the possibility that there was an aircraft in the vicinity.
"This signal was exactly what they were looking for. It's rare. Wright said that it was the first time they have seen anything like this in many years.
He said that it showed clear signs of technology. The frequency it was detected at was a specific frequency. Natural signals are always found over a wide range of frequencies. He says that this is not surprising as there are many easily identified human-made signals that must be sifted through.
Wright states that the signal did not stay at the same frequency as it moved. Wright says that this is what you would expect from objects in space, as the Earth spins and causes a Doppler shift.
It was made even more interesting by the discovery that Proxima Centauri is a red dwarf star located 4.2 light years from Earth and has two planets. One of the planets orbits the star in its habitable zone, where liquid water may exist. It has a minimum mass that is very similar to Earth's.
Researchers searched again for the signal, but it was not there.
It was not aliens, but what would it be? Based on the frequency drift, you can make guesses. Wright suggests that it is likely an inexpensive piece of electronics with a quartz oscillator.
Astronomers are used a disappointment by false alarms
NPR's Seth Shostak, an SETI Institute senior astronomer, says he is ever hopeful of detecting an alien civilization but that his enthusiasm has been "tempered by time and realism."
Shostak says, "We've had false alarms before, and you get all excited but then you find out that it was Homo sapiens not the Klingons."
Radio telescope detected the 2019 signal after it spent 26 hours listening to the Proxima Centauri region. It was not noticed until the next year. Shane Smith, a Hillsdale College undergraduate in Michigan, noticed the signal while going through Parkes data.
Smith was a Breakthrough Listen research intern. He told his supervisor, University of California Berkeley, astronomer Danny Price. Price posted it to Breakthrough Listen Slack. Price was initially skeptical.
He said that his first thought was that interference must be the cause. "But after some time I began to think, this is exactly what we're looking at."
Smith stated that he was both excited and skeptical. He believed there was an easy explanation. He said, "I never thought the signal would cause such enthusiasm."
Sometimes, space mysteries can be explained. Other times they continue to amaze us.
Scientists who seek extraterrestrial intelligence are not the only ones to be concerned by this false alarm.
For example, in 2015, Russian astronomers discovered a fascinating beam-shaped signal using a radio telescope located in Zelenchukskaya at the foot the Caucasus Mountains north Georgia. It turned out that this signal was from a Russian military satellite.
The most famous example of this is the 1977 discovery by astronomers, Jerry Ehman, that a printout from Ohio State University's Big Ear observatory detected a 72-second burst. The data sheet.
Wright claims that the "Wow!" signal has never been satisfactorily explained. Wright claims that the "Wow! Wright says that people have looked at it. "We won't suddenly have an aha moment when we discover what it was." It will be a mystery, unless it happens again, I think.
