Chinese telescope found no extraterrestrial signal. The search continues.


It was a project that launched a thousand interstellar dreams.

Fifty years ago, NASA published a big 253-page book called “Project Cyclops”. It summarized the results of a NASA workshop on how to detect extraterrestrial civilizations. What was needed, the assembled group of astronomers, engineers and biologists concluded, was Cyclops, a vast array of radio telescopes with up to a thousand antennas 100 meters in diameter. At the time, the project would have cost $10 billion. According to astronomers, it could detect extraterrestrial signals from as far away as 1,000 light-years away.

The report began with a quote from astronomer Frank Drake, now professor emeritus at the University of California, Santa Cruz:

At this very minute, with almost absolute certainty, radio waves emitted by other intelligent civilizations are falling on earth. A telescope can be built which, pointed in the right place and tuned to the right frequency, could discover these waves. One day, somewhere among the stars, will come the answers to many of the oldest, most important and most exciting questions that mankind has ever asked.

The Cyclops Report, long out of print but available online, would become a bible for a generation of astronomers drawn to the dream that science could answer existential questions.

“For the very first time, we had technology where we could do an experiment instead of asking priests and philosophers,” said Jill Tarter, who read the report as a graduate student and who dedicated his life in search of extraterrestrial intelligence, said in an interview ten years ago.


It reminded me of Cyclops and the work he inspired this week when news went around the world that Chinese astronomers had detected a radio signal that had the characteristics of an extraterrestrial civilization – namely, it had a very narrow bandwidth at a frequency of 140.604 MHz, an accuracy that nature does not usually achieve by itself.

They made the detection using a giant new telescope called the Five Hundred Meter Aperture Spherical Radio Telescope, or FAST. The telescope was pointed in the direction of an exoplanet named Kepler 438b, a rocky planet about 1.5 times the size of Earth that orbits in the so-called habitable zone of Kepler 438, a red dwarf star hundreds of miles away. light years from here, in the constellation of Lyra. It has an estimated surface temperature of 37 degrees Fahrenheit, making it a candidate for supporting life.

Just as quickly, however, an article from the state-run “Science and Technology Daily” reporting the discovery disappeared. And Chinese astronomers were pouring cold water on the result.

Zhang Tong-jie, chief scientist of the China ET Civilization Research Group, was quoted by Andrew Jones, journalist which follows developments in space and astronomy in China, saying, “The possibility that the suspicious signal is some kind of radio interference is also very high, and it needs to be further confirmed or ruled out. It can be a long process.

“These signals come from radio interference; they are due to radio pollution from earthlings, not aliens,” he wrote in an email.

It has become a familiar story. For half a century, SETI, or the Search for Extraterrestrial Intelligence, has been a mole game, finding promising signals before tracking them to orbiting satellites, microwave ovens and other sources. terrestrial. Dr Drake himself pointed a radio telescope at a pair of stars in 1960 and quickly thought he had struck gold, only to find the signal was stray radar.

More recently, a signal that appeared to come from the direction of the sun’s closest stellar neighbor, Proxima Centauri, was identified as radio interference in Australia.

Just as NASA’s announcement last week that it would make a modest investment in the scientific study of unidentified flying objects was intended to bring rigor and practicality to what many have dismissed as wishful thinking, the Cyclops Workshop at the he agency was held at Stanford for three months in 1971. The conference was organized by John Billingham, an astrobiologist, and Bernard Oliver, who was the head of research for Hewlett-Packard. The men also edited the conference report.

In the introduction, Dr. Oliver wrote that if anything happened to Cyclops, he would consider this the most important year of his life.

“Cyclops was indeed a milestone, largely in setting up a cohesive SETI strategy, as well as the clear calculations and engineering design that followed,” said Paul Horowitz, professor emeritus of physics at Harvard, which then designed and launched its own listening device. campaign called Project Meta, funded by the Planetary Society. Director Steven Spielberg (“ET” and “Close Encounters of the Third Kind”) attended the grand opening in 1985 at Harvard-Smithsonian Agassiz Station in Harvard, Mass.

“SETI was for real!” added Dr. Horowitz.

But what Dr Oliver initially received was just a “Golden Fleece” award from Senator William Proxmire, Democrat of Wisconsin, who fought against what he saw as government waste.

“In my opinion, this project should be postponed for a few million light years,” he said.

On Columbus Day in 1992, NASA launched limited research; a year later, Congress overturned it at the request of Senator Richard Bryan, Democrat of Nevada. Denied federal support since, the SETI effort has limped along, supported by donations to a nonprofit organization, the SETI Institute, in Mountain View, California. Recently, thanks to a $100 million grant, Russian entrepreneur Yuri Milner set up a new effort called Breakthrough Listen. Dr. Horowitz and others have expanded the search to what they call “Optical SETI”, scanning the skies for laser flashes from distant civilizations.

Cyclops was never built, which is just as well, Dr. Horowitz said, “because by today’s standards it would have been an expensive monster.” Technological developments such as radio receivers that can listen to billions of radio frequencies at once have changed the game.

China’s new FAST Large Telescope, also dubbed “Sky Eye”, was built in 2016 partly with SETI in mind. Its antenna occupies a sinkhole in Guizhou, in southwest China. The size of the antenna dwarfs what was the iconic Arecibo Radio Telescope in Puerto Rico, which ignominiously collapsed in December 2020.

Today, FAST and its observers have had their own trial by false alarm. There will be many more, say SETI astronomers.

Those who endure profess to be undeterred by the Great Silence, as it is called, out there. They have always been looking for the long term, they say.

“The Great Silence is hardly unexpected,” Dr Horowitz said, not least because only a fraction of a percent of the Milky Way’s 200 million stars have been surveyed. No one ever said it would be easy to detect this shower of alien radio signals.

“It may not happen in my lifetime, but it will happen,” Dr Werthimer said.

“All signals detected by SETI researchers so far are from our own civilization, not from another civilization,” grumbled Dr. Werthimer in a series of emails and phone conversations. Earthlings, he said, might have to build a telescope on the back of the moon to escape growing radio pollution on Earth and interference from orbiting satellite constellations.

The present moment, he said, could be a unique window to pursue SETI from Earth.

“A hundred years ago the sky was clear, but we didn’t know what to do,” he said. “In a hundred years, there will be no more sky.”


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