Answering the question "Are we alone?" continues to be one of humanity's most intriguing, humbling, and complex questions. At this point, scientists have a pretty solid grasp of the planets in our solar system, but what about the rest of the universe? As discussed in the video below, first, we need to identify all the planets rotating around stars (similar to how Earth rotates the sun). There could be hundreds of thousands of such planets, so this is definitely more of a marathon. Then, we can identify planets most likely to have life-sustaining conditions.
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