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Rigorous Science

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Rigorous Science How far away could Earth detect a projectile travelling at relativistic speeds?

Suppose our alien neighbors woke up on the wrong side of the bed and decided humans would be less annoying if their home planet was hit with a giant artillery shell travelling at half the speed of ...

8 answers  ·  posted 9y ago by Joshua Snider‭  ·  last activity 4y ago by HDE 226868‭

Question modern-age