By 
February 3rd, 2025
Image credit: SETI Institute
Questions for the day, with universal appeal:
If an extraterrestrial civilization existed with technology similar to ours, would they be able to detect Earth and evidence of humanity? If so, what signals would they detect, and from how far away?
A research team led by Sofia Sheikh of the SETI Institute in Mountain View, California, in collaboration with the Characterizing Atmospheric Technosignatures project and the Penn State Extraterrestrial Intelligence Center, set out to detect answers.
Image credit: Sofia Sheikh , et. al
Types of technosignatures
“Our goal with this project was to bring SETI back ‘down to Earth’ for a moment and think about where we really are today with Earth’s technosignatures and detection capabilities,” said Macy Huston, co-author of a new research paper and postdoc at the University of California, Berkeley, Department of Astronomy.
“In SETI, we should never assume other life and technology would be just like ours,” Huston added, “but quantifying what ‘ours’ means can help put SETI searches into perspective.”
Indeed, the research paper notes, future telescopes and receivers could enhance our detection sensitivity or enable us to identify new types of technosignatures, such as other atmospheric signatures of pollution.
Image credit: NOAA
Observable outputs
As Sheikh and colleagues point out, Earth’s present-day technosignatures hold clues to humanity’s culture, society, and biosphere.
“Some of these clues may be straightforward to interpret correctly if the associated technosignature is detected, but others could be interpreted in wildly varying ways, as there are many activities or prior states that could produce the same astronomically observable outputs. We should keep this in mind as we ourselves hypothesize about the ETIs behind any future technosignature candidates.”
To access this paper in the Astronomical Journal — “Earth Detecting Earth: At What Distance Could Earth’s Constellation of Technosignatures be Detected with Present-day Technology?” – go to:
https://iopscience.iop.org/article/10.3847/1538-3881/ada3c7
Also go to this informative video at:
https://youtu.be/Pdg2x3NP2ds?si=7ln-ElTaNrgJXQhA
Credit: ESA/Hubble & NASA
Posted in Space News
