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The Earth with its Sun.
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Aris Multimedia Entertainment, Inc. 1994

The Earth's Orbit

Like all planets in our solar system, the Earth is in an elliptical orbit around our Sun. In Earth's case, its orbit is nearly circular, so that the difference between Earth's farthest point from the Sun and its closest point is very small. Earth's orbit defines a two-dimensional plane which we call the ecliptic.

It takes roughly 365 days for the Earth to go around the Sun once. This means that the Earth is rushing through space around the Sun at a rate of about 67,000 miles per hour! The time it takes for the Earth to go around the Sun one full time is what we call a year.

The combined effect of the Earth's orbital motion and the tilt of its rotation axis result in the seasons.

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The Fall 2009 issue of The Earth Scientist, which includes articles on student research into building design for earthquakes and a classroom lab on the composition of the Earth’s ancient atmosphere, is available in our online store.

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA