Couldn't help noticing Venus the other night next to the crescent moon. It was the brightest and biggest that I've ever seen. Why is it that it always seems to appear next to the crescent moon? Surely, they must be out of synch much of the time.

They are out of sync most of the time. One thing to consider is that you really can only see Venus close to dawn or sunset, because it's between Earth and the Sun, so you have to look kind of in the direction of the Sun to see Venus.

Venus also looks brighter when the Moon is crescent, because a full Moon is around 100 times brighter.

Venus looks brighter, too, when it's in an orbital position that's as close to Earth as it ever gets.

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The Moon rises about 50 minutes later every night. The stars rise about 4 minutes earlier ever night. And, though Venus is a planet, not a star, it's much farther away than the Moon, so its changes in position from night to night aren't as obvious.

The point: we notice Venus when it's bright (like it is now), and a crescent Moon near Venus helps us locate it. It's really not as much of a rule as it seems to be that they appear together.

Thank you for your excellent response.