Credit: New China TV/XinhuaVideo/Inside Outer Space screengrab

Credit: CCTV/Screengrab Inside Outer Space



The first Search for Extraterrestrial Intelligence (SETI) observations have been carried out by China’s Five-hundred-meter Aperture Spherical radio Telescope (FAST) – the world’s largest single-dish radio observatory.

The newly commissioned FAST used a 19 beam receiver in its inaugural SETI work.

Data stream

In a paper published in The Astrophysical Journal that details the FAST SETI testing, a data stream was produced by the SERENDIP VI real-time multibeam SETI spectrometer installed at FAST, as well as its off-line data processing pipelines.

The FAST researchers identified and removed four kinds of radio frequency interference (RFI): zone, broadband, multibeam, and drifting, utilizing the Nebula SETI software pipeline combined with machine-learning algorithms.

Credit: CCTV/Screengrab Inside Outer Space


“After RFI mitigation, the Nebula pipeline identifies and ranks interesting narrowband candidate ET signals, scoring candidates by the number of times candidate signals have been seen at roughly the same sky position and same frequency, signal strength, proximity to a nearby star or object of interest, along with several other scoring criteria,” explains the paper led by Zhi-Song Zhang of China’s National Astronomical Observatories. “This preliminary testing on FAST data helps to validate our SETI instrumentation techniques as well as our data processing pipeline.”

The first observational test of SETI with the 19- beam receiver of FAST was done in July, 2019. Test signals, dubbed “birdies” were injected into the data to demonstrate the pipeline’s RFI removal capability.

SETI searches have the potential to detect whether the neighboring M31 Andromeda Galaxy is a locale of advanced technology and civilizations.
Credit: Bill Schoening, Vanessa Harvey/REU program/NOAO/AURA/NSF

Longer term

For the longer term, FAST is planning a sensitive phased array feed, which could provide roughly 100 simultaneous beams, the paper adds, “excellent for a next generation SETI sky survey.”

The paper explains: “More generally, Earthlings are just beginning to learn how we might detect other civilizations if they are out there. We’ve only had radio technology for a century; that’s a blink of the eye in the history of the universe and life on this planet. We are beginning to explore tiny regions of the large parameter space of possible technosignatures from potential extraterrestrial civilizations.”

While researchers are in an infant stage, the paper adds, “SETI science and technology is growing exponentially. Radio telescope sensitivity has been doubling every 3.6 years for the last 60 years, and SETI spectrometer capabilities have been doubling every 20 months for the last forty years. This SETI sky survey commissioning work is a significant step, leading to a powerful new SETI survey on FAST.”

Frank Drake with cosmic equation to gauge the presence of intelligent life in the cosmos. The Drake Equation identifies specific factors believed to play a role in the development of civilizations in our galaxy.
Credit: SETI Institute

The FAST SETI team concludes that, hopefully, they expect that these ETI signal candidates could come from some warm Earth-size planets in the Milky Way, the number of which can be roughly predicted by the Drake equation.




For access to the paper — First SETI Observations with China’s Five-hundred-meter Aperture Spherical Radio Telescope (FAST) – go to:

Also, for an available draft version dated March 26, 2020, go to:

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