Why do astronomers think that there may be other advanced civilizations

Why do astronomers think that there may be other advanced civilizations

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Why do astronomers think that there may be other advanced civilizations?

What technologies are astronomers using to look for life on other planets? Why?

What are the challenges of looking for Dyson spheres?

Astronomers have theorized that there could be three types of civilizations. What are they? How would they be recognized? Which one has been ruled out so far?

Do you think an advanced civilization may exist in the universe? Why or why not?