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Our Glaciers: Then and Now activity kit helps you see the changes taking place in glaciers around the world. See all our activity kits and classroom activities.
The Earth in its orbit at the solstices and equinoxes.
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The Seasonal Merry-Go-Round

As the Earth travels around the Sun, it remains tipped over in the same direction, towards the star Polaris. This means that sometimes the top half of the Earth is pointing towards the Sun (summer), and sometimes it is pointing away (winter).

Did you notice that when the northern (top) half of the Earth is pointing towards the Sun, the southern (bottom) half is pointing away? This is why people in North America, Europe, Asia, and other places north of the equator have the opposite season of people in South America, Australia, and other places south of the equator.

Halfway in between the times when the Earth is pointing towards or away from the Sun, both parts of the Earth get almost equal amounts of sunlight. These times occur about halfway between summer and winter, so you might guess what we call them... spring and autumn!

Last modified October 31, 2006 by Travis Metcalfe.

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The Summer 2010 issue of The Earth Scientist, available in our online store, includes articles on rivers and snow, classroom planetariums, satellites and oceanography, hands-on astronomy, and global warming.

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