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How far? How big? Distance and Size in Astronomy

Need help trying to comprehend the vast distances between astronomical objects? Are you seeking to understand the relative sizes of planets, moons, asteroids, and comets? This page provides links to information, illustrations, images, animations, and interactives on Windows to the Universe about distance and size in astronomy.

Last modified April 21, 2006 by Randy Russell.

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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