Highlands, Maria, Craters, Rilles And The History of the Moon Features of the Moon Highlands, Maria, Craters, Rilles And The History of the Moon

Highlands and Maria There are two main types of terrain on the Moon Highlands: Mountainous areas of a light color. Maria: Low, Flat ancient lava plains, dark in color.

Craters The Moon’s Surface is dotted with craters. They are the result of the impacts of meteoroids The most recent craters have light colored “Rays” of debris that streak out away from the crater Craters have scattered dust all over the Moon creating a soil-like layer called the Regolith Unlike craters on Earth where tectonic and erosion forces gradually erase them, On the moon there are no such forces so they last forever

Sometimes the impacts had enough energy to melt the crust These Craters have central peaks. Others weren’t

Rilles Narrow snake-like canyons Supposed to have been formed by ancient lava flows

The Early Moon Early in its History the Moon still had a fluid mantle like the Earth During this period asteroids struck it causing giant lava flows that became the Maria Rilles also formed during this volcanically active period.

The Moon Cools How fast something cools depends on size. Since the Moon is ¼ the radius of the Earth it cools at least four times quicker

The Recent Moon Now the Moon’s Mantle is solid and rigid There is no more volcanic activity The Newest features on the Moon are the Craters with Rays The “far-side” of the Moon is more exposed to meteoroids and thus is completely covered with craters.