HEATKEYS

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USGS Topographic Maps

Definition of word from the Merriam-Webster Online Dictionary with audio pronunciations, thesaurus, Word of the Day, and word games.

Online Dictionary - Multiple dictionaries including: English dictionary, medical dictionary, legal dictionary, financial dictionary, computer dictionary, thesaurus, dictionary of acronyms and abbreviations, dictionary of idioms, thesaurus, Columbia e...

This web site of Steve Reynolds, geology professor at Arizona State University, contains numerous color photographs, 3D perspectives, and information about the Geology of Arizona, Landscapes of the Southwest, structural geology, science-education...

The National Geophysical Data Center (NGDC) is part of the US Dept of Commerce, National Oceanic & Atmospheric Administration, National Environmental Satellite, Data, & Information Service

The Jet Propulsion Laboratory is the lead U.S. center for robotic exploration of the solar system, and conducts major programs in space-based Earth sciences and astronomy. JPL spacecraft have visited all of the planets from Mercury to Neptune.

The Jet Propulsion Laboratory is the lead U.S. center for robotic exploration of the solar system, and conducts major programs in space-based Earth sciences and astronomy. JPL spacecraft have visited all of the planets from Mercury to Neptune.

International führender Wissenschaftsverlag - Wissenschaft, Technik, Medizin, Architektur, Wirtschaft und Verkehr - Zeitschriften, Bücher und EContent.