Alien Probes May Have Already Visited Earth, Scientist Says

Scientists suggest that alien probes may have already visited Earth, given that Earth has had detectable biosignatures for 3 billion years. However, the vast distances and speed of light limit make it extraordinarily difficult for extraterrestrial civilizations to send probes. Even if aliens could travel faster than light, they would still have to deal with space debris that could damage their crafts. Despite these challenges, scientists believe it’s worth continuing the search for signs of extraterrestrial life.

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