The sun's vertical rays are directly over the Tropic of Capricorn, which is located at 23.5 degrees South latitude. The angle between the horizon and the vertical position of the sun is 90 degrees at the equator and gets smaller as you go north or south of the equator. At the tropics, the maximum height that the sun reaches above the horizon is 90 degrees all around the clock, no matter what part of the year it is. At other latitudes, the sun will set sometime during the night while you're still awake and then rise again in the morning. The sun's rays are always angled upward at a horizontal distance from the horizon called the altitude. At the equator, the altitude of the sun is 90 degrees all day every day, but it decreases toward zero at both the north and south poles. At the North Pole, where the earth's rotation is fastest, the sun makes one complete rotation in 24 hours, even though it doesn't move. At this rate, the sun would drop below the horizon for three minutes before rising again. At the South Pole, where the earth's rotation is slowest, the sun takes four months to make one full rotation.