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by sailingparrot
2095 days ago
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Radio signal is not the only way to detect presence of other civilizations. Von Neumann style probes, Dyson spheres etc. Current estimates place the number of planets in our galaxy at 100 billions. And some of the stars in our galaxy are ~6 billions years older than our sun, that's a hell lot of time for a civilization to develop massively considering the technological progress we have had in a just a few thousands of years. |
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