The graphic below shows that many concentric 'donut' craters are located around the edges Oceanus Procellarum (Ocean of Storms) as well as clustering in other places. However, these craters are not at all randomly placed. However, this hypothesis has some drawbacks.įirstly, if this was just the cause of two impactors hitting the same area, you would expect to find concentric craters randomly scattered around the lunar surface.

While there have been several ideas about their origin, including double impacts, the currently favored hypotheses involve volcanic processes and compositional variations.Ĭontrolled Feature Mosaics made from LROC Narrow Angle Camera (NAC) images allow us to take a closer look at these mysterious craters.īullseye! One crater formed after an impactor hits the surface, then some time later, a smaller impactor approaches and creates a smaller crater, perfectly centered within the first. Many questions remain on the origin of donut craters. These donut-shaped formations are commonly known as concentric craters. Somewhere in between is Bell E, a small crater located within the larger Bell crater. There are simple craters and complex craters with ring structures and mountains at the center. But sometimes, we find craters that look like donuts! Craters not only vary in shape but also in complexity. Most are shaped like circles, some like ovals, and there are even the occasional square craters.

Impact craters dominate the lunar landscape.

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