Have you ever looked at the globe or a map and wondered..."what is this line? The Tropic of Cancer? And why is there another line beneath the equator called the Tropic of Capricorn? Yes, me too. I have wondered the same thing. The Tropic of Cancer is the circle marking the latitude 23.5 degrees north, where the sun is directly overhead at noon on June 21, the beginning of summer in the northern hemisphere. The Tropic of Capricorn is the circle marking the latitude 23.5 degrees south where the sun is directly overhead at noon on December 21, the beginning of winter in the northern hemisphere. The equator is the circle where the Sun is directly overhead at noon on the equinoxes. The Arctic and Antarctic Circles are located at ±66.5 degrees latitude. Note that 66.5 + 23.5 equals 90 degrees. This means that on December 21, when the Sun is directly over the Tropic of Capricorn at noon, it will not be visible from the Arctic Circle. So above the Arctic Circle, there is a period during the winter when the sun remains below the horizon. The same is true of the Antarctic Circle during Southern Hemisphere winter. On June 21st, when the sun is directly over the Tropic of Cancer at noon, it is not visible from below the Antarctic Circle. Huh? During the northern hemisphere's summer the sun is directly overhead if you were standing at the Tropic of Cancer. The band around the Earth bounded by the Tropics of Cancer and Capricorn define the 'tropical latitudes' (or simply the 'tropics') where it is possible to have the sun directly overhead. Ohhhh! I get it! How fascinating that someone would care to figure that out! I love hanging around smart people and glad that I learned this. So again, it is all about the tilt of the Earth in space and in relation to the angle of the Sun's rays. Every map has the Tropics on it, so now I can appreciate them better.... Okay, yeah, that's enough maps...you get the picture.
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Mrs. TaylorI love science! Everything about the world is interesting and never boring. I love to study plants, animals, insects, and people. My favorite subjects are my students who are the most unique organisms on the planet! Categories |