PBS Space Time

Dark Forest: Should We Not Contact Aliens?

In 1974 we sent the Arecibo radio message towards Messier 13. The message was mostly symbolic; we weren’t really expecting a reply. Yet surely other civilisations out there are doing the same thing. So, why haven’t we heard anything? What if the silence from the stars is a hint that we shouldn’t be so outgoing? What if aliens are deliberately keeping quiet for fear that they might be destroyed?

Dark Forest: Should We Not Contact Aliens?

14m 12s

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