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This abundance suggests the possibility that intelligent life, or even pre-existing civilizations, could have emerged elsewhere long before humans. It's conceivable that civilizations might have developed, sent probes or spacecraft, and expanded their reach well before humanity's inception.
The Possibility of Extraterrestrial Visitors
Given the vast number of stars and the potential age of other civilizations, some scientists argue that extraterrestrial observers or explorers could have already arrived or sent probes into our cosmic neighborhood. The question remains: have they visited us unnoticed?