Columnist Leonard David

Did China just detect signals from an alien civilization?

The Five-hundred-meter Aperture Spherical radio Telescope (FAST) in southwest China's Guizhou Province.
China's Five-hundred-meter Aperture Spherical radio Telescope, or FAST. (Image credit: NAO/FAST)

The internet is abuzz with rumors that China may have picked up signals from an alien civilization.

The news centers on observations by China's "Sky Eye" — the Five-hundred-meter Aperture Spherical radio Telescope (FAST), which is located in southwestern Guizhou province.

One report, by the state-backed Science and Technology Daily, cited Zhang Tonjie, chief scientist of an extraterrestrial civilization search team co-founded by Beijing Normal University, the National Astronomical Observatory of the Chinese Academy of Sciences and the University of California, Berkeley.

Related: The search for alien life

Zhang is reported to have said that the team spotted two sets of intriguing signals in 2020 while sifting through FAST data gathered in 2019. Another signal was apparently picked up this year in data gathered on exoplanet targets. 

However, Zhang reportedly also underscored the possibility that the signals are products of radio interference. Follow-up FAST observations are reportedly on tap. (The Science and Technology Daily story has since been removed from the outlet's site.)

To get some perspective about the FAST rumors, Inside Outer Space reached out to Dan Werthimer, the Marilyn and Watson Alberts SETI (search for extraterrestrial intelligence) Chair in the Astronomy Department and Space Sciences Lab at the University of California, Berkeley. He works with the Beijing Normal University SETI researchers.

Werthimer threw cold water on the possibility that the FAST signals were produced by advanced aliens.

"These signals are from radio interference; they are due to radio pollution from Earthlings, not from ET. The technical term we use is 'RFI' — radio frequency interference. RFI can come from cell phones, TV transmitters, radar, satellites, as well as electronics and computers near the observatory that produce weak radio transmissions," Werthimer said.

"All of the signals detected by SETI researchers so far are made by our own civilization, not another civilization," Werthimer added. "It's getting hard to do SETI observations from the surface of our planet. Radio pollution is getting worse, as more and more transmitters and satellites are built. Some radio bands have become impossible to use for SETI."

Werthimer said that Earthlings might eventually have to go to the far side of the moon to do SETI work.

"A radio telescope on the backside of the moon would be shielded from all of our planet's radio pollution," he said.

Leonard David is author of the book "Moon Rush: The New Space Race," published by National Geographic in May 2019. A longtime writer for, David has been reporting on the space industry for more than five decades. Follow us on Twitter @Spacedotcom or on Facebook.  

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Leonard David
Space Insider Columnist

Leonard David is an award-winning space journalist who has been reporting on space activities for more than 50 years. Currently writing as's Space Insider Columnist among his other projects, Leonard has authored numerous books on space exploration, Mars missions and more, with his latest being "Moon Rush: The New Space Race" published in 2019 by National Geographic. He also wrote "Mars: Our Future on the Red Planet" released in 2016 by National Geographic. Leonard  has served as a correspondent for SpaceNews, Scientific American and Aerospace America for the AIAA. He has received many awards, including the first Ordway Award for Sustained Excellence in Spaceflight History in 2015 at the AAS Wernher von Braun Memorial Symposium. You can find out Leonard's latest project at his website and on Twitter.