The Moon

The Moon has fascinated mankind throughout the ages. By simply viewing with the naked eye, one
can discern two major types of terrain: relatively bright highlands and darker plains. By the middle
of the 17th century, Galileo and other early astronomers made telescopic observations, noting
an almost endless overlapping of craters. It has also been known for more than a century that the
Moon is less dense than the Earth. Although a certain amount of information was ascertained
about the Moon before the space age, this new era has revealed many secrets barely imaginable
before that time. Current knowledge of the Moon is greater than for any other solar system
object except Earth. This lends to a greater understanding of geologic processes and further
appreciation of the complexity of terrestrial planets.