A team of astronomers from Harvard and other institutions are collaborating on a new project to scan the skies for technological signatures from alien civilizations.
It’s a noteworthy new project, as it’s the first to receive a NASA grant for SETI-specific research in more than 30 years, according to a statement.
“Technosignatures relate to signatures of advanced alien technologies similar to, or perhaps more sophisticated than, what we possess,” said Avi Loeb, the chair of the Harvard astronomy department Harvard, in a statement. “Such signatures might include industrial pollution of atmospheres, city lights, photovoltaic cells (solar panels), megastructures, or swarms of satellites.”
Loeb’s collaborators say that the discovery of myriad exoplanets in recent years has the potential to shake up SETI research.
“The Search for Extraterrestrial Intelligence has always faced the challenge of figuring out where to look,” said Adam Frank, professor of physics and astronomy at the University of Rochester, and the primary recipient of the grant, in the statement. “Which stars do you point your telescope at and look for signals?”
“Now we know where to look,” he added. “We have thousands of exoplanets including planets in the habitable zone where life can form. The game has changed.”
An initial study will scan the skies for signs of extraterrestrial solar panels and pollutants, according to the team — two possible indicators of the presence of technological activity beyond Earth.
“The nearest star to Earth, Proxima Centauri, hosts a habitable planet, Proxima b,” explained Loeb. “The planet is thought to be tidally locked with permanent day and night sides. If a civilization wants to illuminate or warm up the night side, they would place photovoltaic cells on the day side and transfer the electric power gained to the night side.”
By looking for specific wavelengths, the astronomers are hoping they could get a chance of spotting sunlight reflecting off those hypothetical solar panels.
Polluting gases in the atmospheres of other planets could also indicate the presence of intelligent life. To Loeb, a different civilization would show “detectable signs of artificially produced molecules,” like refrigerant gases we’ve released into Earth’s atmosphere.
“The fundamental question we are trying to address is: are we alone?” Loeb pondered. “But I would add to that: even if we are alone right now, were we alone in the past?”