# All Questions

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### Why can't light escape from a black hole?

I've heard that light can't escape from a black hole. Can it? If not, why?
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### Why do sunspots appear dark?

Sunspots, such as this one, appear dark: Why?
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### Amateur observing targets for binary star systems?

Are there any easily resolvable, binary star, observing targets visible from ~N40°? I'd like to be able to show, in one observing session, Mizar and Alcor (naked eye resolvable), another with ...