THE LUNAR HIGHLANDS
Regions of both the near side and far side of the Moon not covered by mare basalt are called highlands. The highlands consist of the ancient lunar surface rock, anorthosite, and materials thrown out during the creation of the impact basins. Relatively young basins are shown in light colors; the oldest basins are in dark colors.

ORIGIN OF ANORTHOSITE
The ancient crust of the Moon is believed to have been composed of the rock, anorthosite, a calcium-rich white rock. This ancient crust has been smashed and redistributed by countless meteoric impacts. One explanation for the presence of anorthosite in the lunar crust is based on the assumption that the Moon was once molten. Plagioclase, a relatively light mineral, crystallized as the Moon cooled and solidified. This mineral floated toward the surface and formed anorthosite. Heavier minerals sank and produced the denser interior of the Moon.

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Racing to Space
The Moon decision
To reach the moon
Apollo 11
Later Apollo missions
What we learned about the Moon
After the Apollo Program


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Created: 7/99