what would a school bus size of asteroid do to earth?

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Although it's not on an impact trajectory with Earth, if it were, the space rock would almost certainly break up high in the atmosphere, becoming a bright meteor known as a fireball.Sep 22, 2020

School Bus-Size Asteroid to Safely Zoom Past Earth - NASA

NASA (.gov)

https://www.nasa.gov/.../school-bus-size-asteroid-to-safel...