Why does the Moon always shows the same face to the Earth? Why is the Moon's rotation period the same as the length of time it takes to orbit the Earth? Why are there two tides a day? These questions and more are answered here.

[Free Registration/Login Required] An informational text about outer space. A question sheet is available to help students build skills in reading comprehension.

This site from NASA has information on the Galileo space mission, which launched in October 1989. In spite of technical problems, Galileo transmitted enormous amounts of new data, especially about Jupiter and its satellites and rings,...