What Are These Dark Spots on the Moon? (No, Not Crater!)

In ancient times, it was believed that the areas that appeared dark and gray were the sea. Light and gray areas on the Moon’s surface were considered land. However, observations made over time revealed that these thoughts were wrong.

Subsequent observations of the Moon showed that the light gray areas were high, rugged areas covered with craters. Dark gray areas were found to be low and flat areas. But did these observations illuminate the truth? Or was more answers needed? Let’s see together.

According to ancient astronomers, these dark areas on the Moon’s surface were called Maria in Latin. Maria means sea.

Although these regions cover approximately 17 percent of the Moon’s surface, most of them remain on the surface visible from Earth. It is also known that there are fewer meteorites in dark-colored regions than in lighter-colored regions. In other words, the structures called Maria are actually young geological structures. During the formation of the Marias, the number of meteorites hitting the surface of the Moon increased due to the dust cloud surrounding the Moon. The gravitational effects of the Sun and other celestial bodies have reduced the number of meteorites hitting the Moon over time. In short, the formation patterns and chemical compositions of these dark and light colored regions are not similar to each other.

In other words, we can understand that these structures, called Maria, were formed as a result of the coating of lava flows from the crater floors.

Robert Wagner of Arizona State University states that these pits on the Moon’s surface are formed by the collapse of the underground surface due to vibrations caused by the falling meteorite. In fact, it is thought that a molten rock flowed under the surface, causing the long tube-like passages over time. This causes the Moon’s surface to collapse over time.

The meteorite, which hits the surface of the Moon with great force, can blow the surface up, causing the lava below to come out. Thus, we can say that different voids may form under the surface. In fact, Wager says that the ages of these pit layers can be determined thanks to the examinations to be made on the surface of these pits. Moreover, it is thought that solar wind particles trapped in these pits may also be found.

Of the more than 200 holes seen to date, 29 have been found to be younger than one billion years. Scientists have even classified them within the ‘Copernicus’ crater. It is known that all three holes discovered by the spacecraft Kaguya are among this classification. After all, you should know that those pitted areas you see on the Moon’s surface are made up of solidified lava.

Sources: 1, 2