SETI admits its search for ET may be too narrowly focussed

"If a signal gets broadened by its own star's environment, it can slip below our detection thresholds, even if it's there, potentially helping explain some of the radio silence we've seen in technosignature searches. This statement from Dr. Vishal Gajjar highlights how stellar environmental factors may cause detectable signals to become invisible to current SETI instruments."

"The researchers concluded that broadening can exceed 10-100 Hz for most systems and suggests that's enough to shift otherwise detectable technosignatures below the sensitivity thresholds of current search pipelines optimized for sub-Hz channel. This finding demonstrates that signal distortion from stellar environments is substantial enough to render extraterrestrial transmissions undetectable."

"The authors think their work may offer a compelling explanation for the apparent absence of detected narrowband radio technosignatures. This conclusion suggests that the lack of confirmed extraterrestrial signals may result from methodological blind spots rather than the absence of alien civilizations attempting communication."

The SETI Institute has traditionally searched for narrowband radio signals from extraterrestrial civilizations while compensating for interstellar distortion. New research reveals that solar winds and coronal mass ejections within alien star systems may broaden signals enough to make them undetectable by current search methods. Analysis of human-made space probe data shows signal broadening exceeding 10-100 Hz across multiple missions, sufficient to push otherwise detectable technosignatures below sensitivity thresholds of existing detection pipelines. This finding suggests the apparent absence of detected narrowband radio signals may reflect search methodology limitations rather than the absence of extraterrestrial transmissions.

Read at Theregister