|MadSci Network: Astronomy|
If Mars were suddenly to blow up, it would have zero immediate effect on Earth. The only long-term effect would be an increase in meteor activity as some of the debris found its way into Earth orbit. In terms of the rest of the universe, the impact would be nonexistent. Our entire solar system is only a flyspeck in our galaxy, and our galaxy is only a flyspeck in the universe.
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