This web page, authored and curated by David P. Stern, describes the causes of naturally occurring magnetite magnets, or 'lodestones.' It explains theories about the function of lightening and heat in such processes, and...

Created by Bill Arnett, "The Nine Planets" is an overview of the history, mythology, and current scientific knowledge of each of the planets, moons, and some other objects in our solar system. Text, images, sounds, and...

This web page, created by David P. Stern, describes observations that show the earth is a sphere and the history of these observations. The round shape of the Earth may be inferred from the existence of a horizon at sea....

In this activity by Larry and Sheryl Braile, students construct a model of the Earth's interior to help them visualize its main regions (inner core, outer core, mantle, crust) and practice their problem solving and math...

This site is part of Visible Earth, which is hosted by the National Aeronautics and Space Administration (NASA), and contains a searchable directory of images, visualizations, and animations of the Earth. The agriculture...