How much astronomy can you study with the naked eye? Learn more about the ways scientists explore the galaxy with a short reading passage and set of short-answer questions.

"Humans have become a geologic agent comparable to erosion and [volcanic] eruptions ..." Paul J. Crutzen, a Nobel Prize-winning atmospheric chemist. Using Landsat imagery, scholars create a grid showing land use type, such as urban,...

A video and a short quiz on the basic concepts and vocabulary for understanding light energy.