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Science, Evolution, and Creationism, by the National Academies, focuses on teaching evolution in today's classrooms. Check out the other publications in our online store.

Compare Planet Sizes

This interactive lets you compare the sizes of planets in our Solar System. It does NOT show where they are in the Solar system or how far apart they are from each other.

Move the slider to zoom in and out. You can hide the planet labels text and/or the distance scales if you want to.

(Note: If you cannot see the animation below, or it is not working properly, you may need to download the latest Flash player.)

Last modified April 20, 2006 by Randy Russell.

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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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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF