Concept explainers
Why are we more likely to be able to detect a deliberately broadcast “beacon” signal than, say, the television broadcasts of a distant civilization? (a) because we expect beacon signals to be far more common (b) because our current technology is probably sensitive enough to detect beacons but not much weaker television transmissions (c) because television is a sociological phenomenon and beacons are not, so we’d expect all civilizations to have beacons but not all to have television
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