Astronomy

How wide is Mercury's largest crater?

How wide is Mercury's largest crater?

Caloris Planitia is 1,400 kilometers across.   A better name for it might have been Deep Impact.

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How fast is the speed of light?

How fast is the speed of light?

It’s 299,792,458 meters/second (or 186,000 miles/second). It’s sometimes called the "universal speed limit".

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