August 15, 1977 is a date that every astronomer knows: at 11:57 pm that night, the Ohio University Radio Observatory’s telescope picked up a signal that lasted exactly 72 seconds, and that would go down in the history of astronomy with the name of “Wow” (in English, “Wow”). 43 years later, the sign remains a mystery.
“When astronomers examine an as-yet unexplored piece of the sky, they often stumble across something surprising that no one has predicted. Our goal is to look for very brief but powerful signs of an advanced civilization,” explained one of those involved in the PANOSETI project, the chief technologist from the SETI Research Center at the University of California at Berkeley, Dan Werthimer has been involved in the search for extraterrestrial intelligent life for 45 years.
Constant search for ETs
Acronym for Pulsed All-sky Near-infrared Optical SETI (or SETI Pulsed Near Infrared Optical Across the Sky), the first stage of the PANOSETI project will be complete when the 160 telescopes dedicated to the work are scanning the firmament in search of signs of extraterrestrial life (SETI means search for extraterrestrial intelligence, or search for extraterrestrial intelligence).
PANOSETI will undertake a constant search for flashes of optical or infrared light, and this is already happening at the Astrograph Dome at the Lick Observatory in California. The project, started two years ago, aims to separate pulses with technological signatures (which could have been emitted, for example, for the purposes of interstellar communications or energy transfer) from those that have a natural origin.
The program envisions pairs of observatories around the world, with geodesic domes like the faceted eye of a fly and 198 telescopes 1.5 meters in diameter each, collecting signals from the sky.
The location for the second observatory has not yet been chosen, but it will not be more than 1.5 kilometers away. This is essential to get a “stereo” view of the night sky: what one sees, the other will confirm as coming from space or discard the signal as generated by the Earth’s atmosphere.
eyes all over the sky
What excites astronomers is the power of PANOSETI to capture a greater number of star systems, extending the space tracking time and recording signals that occur in minimal time spans (on the nanosecond scale).
“How likely is it that we can detect extraterrestrial signals? We have no idea,” said the astronomer at the University of California at San Diego and lead researcher on the project, Shelley Wright.
A single telescope has a field of view wide enough to see 20 full moons at once. This is due to two new technologies in astronomy. One of them is the plastic lens of telescopes, light and flat; the other comes from medicine: optical and infrared detectors designed for diagnostic scanners.
The team is now working to develop cameras capable of accurately capturing the exact moment when a photon, pulsing for a millionth of a second, touches the telescope’s lens array – and expects a “Wow” to repeat.