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We now offer the Cool It! card game in our Science Store. Cool It! is the new card game from UCS that teaches kids about the choices we have when it comes to climate change.

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.

Shop Windows to the Universe Science Store!

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 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