7 times a total solar eclipse revolutionized science

Tech Insider
Dark clouds nearly cover a partial solar eclipse.
Clouds can block out and ruin the total solar eclipse.

Laurie Ambrose/Getty Images

Albert Einstein used to ponder these 5 mind-melting questions for fun. Can you figure them out?

Tech Insider
Photo of Albert Einstein in front of a chalkboard.
Albert Einstein pondered very complex ideas but tried to make them accessible.

Hulton Archive / Stringer / Getty Images

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