The Sunrise and Sunset Thread

At really high latitudes like that, the sun hits at a very slanted angle so there's less of a difference between night and day.

For example, at Cape Columbia, even though the day is roughly 9.5 hours long, the peak sun angle is only about 3.7 degrees, so the sun stays really close to the horizon, while at Barneo, the peak sun angle is -1 degrees, which is just below the horizon.

The sun position throughout the day at higher latitudes changes less than in lower latitudes, which is another reason why the day length changes quicker as well. For example at 84 N, the peak sun angle on September 1st is only 14 degrees. However, since the sun position at 84 N only changes by about 12 degrees, it only goes down to 2 degrees, meaning they have 24-hour darkness with low sun angles. 24-hours darkness will start when the sun drops another 14 degrees, or by about October 6th. So in a month they go from 24-hour daylight to 24-hour darkness.

At 30 N, the sun position changes about 120 degrees throughout the day, so even on June 21st when the sun angle peaks at about 84 degrees, it goes all the way down to -36 degrees during the middle of the night. Hence, it's impossible for them to have 24 hour daylight or darkness.