Astronomy

520	Amazing Space
520	The Astronomical Society of the Pacific
520	The Astronomy Cafe: Ask the Astronomer section, has over 3,000 archived answers
520	Astronomy Picture of the Day
520	Down to Earth Astronomy
520	Earth and Moon Viewer
520	Earth from Space | Smithsonian Institution
520	Earth, Moon and Sun: An Interactive Unit
520	Educational Space Simulation Project
520	Explore Mars Now
520	Gemini Observatory Image Gallery
520	History of Astronomy
520	Hubble
520	Hubble Deep Field Academy
520	HubbleSite
520	International Space Station
520	Kids Astronomy
520	The NASA Homepage
520	NASA International Space Station
520	NASA Planetary Photojournal
520	NASA Sites for Kids
520	New Scientist: Space
520	SOHO Explore
520	Star Myths
520	StarChild: A learning center for young astronomers
520	Windows to the Universe: From the University of Michigan--beautiful site
520	The World of Astronomy: From Bloorstreet
520	U.S. Naval Observatory, Astronomical Data
523.1	GALEX - Galaxy Evolution Explorer
523.1	Milkyway@Home
523.2	Solar System Exploration: Home Page
523.2	Solar System, Solar System Information, Facts, News, Photos ...
523.2	Views of the Solar System
523.4	Exploring The Planets - Gallery Entrance
523.4	Planet Size Comparison
523.4	Welcome to the Planets: Best images from NASA's planetary exploration program
523.4	The Nine Planets: A Multimedia Tour of the Solar System
523.4	Planetary Fact Sheets
523.4	The Planetary Society
523.4	Welcome to the Planets: Best images from NASA's planetary exploration program
523.43	Mars Exploration Program: Explore Mars up Close
523.5	Mars Meteorites
523.7	Virtual Sun
523.8	Constellation Mythology
523.8	The Constellations and their Stars
523.8	Constellations from Enchanted Learning
523.8	Constellations from Kids Astronomy
523.8	The Deep Photographic Guide to the Constellations
525	Earth and Moon Viewer: View the earth and moon from any angle, day or night

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