https://www.universetoday.com/138516/res...lizations/
EXCERPT: . . . “In our article, we define a “technosignature” as any measurable property or effect that provides scientific evidence of past or present technology, by analogy with “biosignatures,” which provide evidence of past or present life.” [...] What they found was that of the 850,000 candidate signals, about 99% of them were automatically ruled out because they were quickly determined to be the result of human-generated radio-frequency interference (RFI). Of the remaining candidates, another 99% were also flagged as anthropogenic because their frequencies overlapped with other known sources of RFI – such as GPS systems, satellites, etc. The 19 candidate signals that remained were heavily scrutinized, but none could be attributed to an extraterrestrial
source....
MORE: https://www.universetoday.com/138516/res...lizations/
EXCERPT: . . . “In our article, we define a “technosignature” as any measurable property or effect that provides scientific evidence of past or present technology, by analogy with “biosignatures,” which provide evidence of past or present life.” [...] What they found was that of the 850,000 candidate signals, about 99% of them were automatically ruled out because they were quickly determined to be the result of human-generated radio-frequency interference (RFI). Of the remaining candidates, another 99% were also flagged as anthropogenic because their frequencies overlapped with other known sources of RFI – such as GPS systems, satellites, etc. The 19 candidate signals that remained were heavily scrutinized, but none could be attributed to an extraterrestrial
source....
MORE: https://www.universetoday.com/138516/res...lizations/