The diagram to the left shows how the Sun may appear to move through your sky on an equinox, if you live at a latitude of 40° N, around Topeka, Kansas for instance. The Sun is in between its altitude on the summer solstice (the highest point) and its altitude on the winter solstice (the lowest point). In a similar way, spring and autumn are in between summer and winter; the temperatures are neither very hot nor very cold, and the weather is not as extreme as in summer and winter. Compare the Sun's height
to what you would see in the winter or in
the summer.
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The upper panel shows that on an equinox (which occurs around March and September 21), neither half of the Earth points directly towards the Sun. In fact, the Sun is at the equator, so both halves of the Earth are getting about the same amount of sunlight. For you in Topeka, the altitude of the Sun is about 50°, in between its altitude on the solstices. The bottom panel shows how this looks to someone standing on the ground in Topeka. Equinox literally means "equal night". On the vernal (spring) and autumnal (fall) equinoxes, day and night are the same length. Neither hemisphere gets more sunlight than the other, so both have similar seasons (fall in one hemisphere and spring in the other).
How high the Sun gets in your sky, and how long it is above the
horizon during the day, depend not only on the season, but also on
your latitude. |
The upper panel shows that on an equinox (which occurs around March and September 21), neither half of the Earth points directly towards the Sun. In fact, the Sun is at the equator, so both halves of the Earth are getting about the same amount of sunlight. For you in Topeka, the altitude of the Sun is about 50°, in between its altitude on the solstices. The bottom panel shows how this looks to someone standing on the ground in Topeka. Equinox literally means "equal night". On the vernal (spring) and autumnal (fall) equinoxes, day and night are the same length. Neither hemisphere gets more sunlight than the other, so both have similar seasons (fall in one hemisphere and spring in the other).
How high the Sun gets in your sky, and how long it is above the
horizon during the day, depend not only on the season, but also on
your latitude.
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Last modified prior to September, 2000 by the Windows Team
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