The moon is covered in craters of every type.
Craters come in all different shapes and sizes. This might be caused by the length of time since the impact occurred or it may be based on the size of the object that caused the impact. These different causes and effects related to the creation of craters have led to craters on Earth and the moon having a classification system.
Simple Craters
Simple craters are the most common type of craters. These are usually smaller craters, both in diameter and in depth. Most simple craters are anywhere between five kilometers to 20 kilometers from one edge to the other. They usually are a very simply bowl shape and are a circular shape. These are the most common craters on Earth as well as on the surface of the moon.
Complex Craters
Complex craters are not as straightforward as simple craters, just as their name implies. In the center of a complex crater is a peak. This peak can vary greatly in height. The peak in the center of a complex crater is caused by the reaction to the impact of the original object. When the object collides with the surface of the ground, the ground will sometimes rebound, causing the peak in these craters.
Multi-ring Craters
Multi-ring craters are much less common on Earth than they are on the moon. These craters are caused by a very strong impact, or a heavy object impacting the main body. When the impact occurs, it causes ripples along the surface of the ground in the shape of the crater, just as when a stone is dropped in water. The ripples harden and form cracks in the ground that remain long after the impact. These ripples are what give the multi-ring crater its multiple rings.
Enigmatic Craters
Enigmatic craters are any craters that do not quite fit in the other categories. This blanket category is used for these unusual craters due to how seldom they occur. Elongated craters, for example, are caused by the angle of impact when forming a crater. Some craters, however, have a shape that scientists are unable to explain. Two examples of this are the Messier and Messier A craters on the Earth's moon. Scientists are unsure of what caused the unusual shape of these two craters.
Tags: craters Earth, center complex, center complex crater, complex crater, craters Earth moon, Earth moon, impact These
