What is the primary reason the Harvest Moon provides extended periods of light after sunset?

Answer

The Moon’s path makes a shallow angle with the eastern horizon

Around the time of the Harvest Moon, the Moon’s path (the ecliptic) makes a shallow angle with the eastern horizon in the Northern Hemisphere, causing the moonrise time to be much closer to the previous night's rise.

What is the primary reason the Harvest Moon provides extended periods of light after sunset?
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