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The SETI Institute is after alien signals. Assuming another world is beaming a 1-million-watt radio signal in our direction, how far away can that source be before the signal is lost in intergalactic noise? | Astronomy.com
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The SETI Institute is after alien signals. Assuming another world is beaming a 1-million-watt radio signal in our direction, how far away can that source be before the signal is lost in intergalactic noise?

Don Schmidt, Oro Valley, Arizona
RELATED TOPICS: EXTRATERRESTRIALS
Spacebeacon
Many people assume that radio signals only can travel a limited distance before they are, like the Robinson family, lost in space. They believe there’s a range beyond which transmissions reach an intensity lower than background static and therefore become thoroughly undetectable.

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