What Are the Dark Spots on the Moon Called?

When gazing into the night sky and seeing our closest neighbor, the moon looks magnificent to the naked eye. However, when looking at the moon in the night sky, we are often left with questions. When looking at the moon, we see large dark splodges and think, what are the moon’s dark spots called?

The moon’s large dark spots are known as lunar maria, which is Latin for moon seas. Unlike our seas on Earth full of water, the seas on the moon were full of molten lava.

Okay, so we know that they were seas full of molten lava, but how did they get there? How big are they? And what did we first think they were? Let’s find out below.

How did the moon seas happen?

In the early solar system, there was lots of impact on the surface of the early moon. The impacts triggered volcanism that created vast pools of molten lava on the surface of the early moon.

After many years of impacts on the new moon and the seas of molten lava was created. The molten lava, over many years, started to solidified until it was completely dry. We were then left with the dried-up seabed of lava rock. The rock is named basalt; this rock was collected on lunar space missions.

These dried up sea beds are what we see from the earth that looks like big dark splodges on the moon’s surface.

Early Astronomers Thoughts

Early astronomers believed the dark splodges on the surface of the moon were seas full of water. With this belief, the splodges were named lunar maria that means moon seas in Latin.

With this belief, many people believed if there were water on the moon, it would be possible to live on the moon. Many of the moon’s myths come from when people thought the moon was full of water.

Despite being wrong about the seas being full of water, the yesteryear astronomers were on the right track. With the growing space expeditions, our knowledge about the planets in our solar system has grown.

It is from yesteryear that most things with astronomy are named, and they have just stuck. It is the same with the names of full moons.

How big Are The Moon Seas?

It may leave us a little confused about why we can see them from the earth so clearly. The reason being is the sheer size of the sea moons.

The biggest moon sea is the Oceanus Procellarumv; this name converts to Ocean of Storms. Oceanus Procellarumv is a staggering 1000 miles by 480 miles, which is eyewatering big and around 100 miles larger in length than Great Britain.

The Oceanus Procellarumv dominated the Moon’s western edge and is easily spotted when looking to the moon’s western edge when there is a full moon during the 29.5 moon phase.


So we have discovered that the moon is covered in seas, but the name is a little misleading, and they are full of molten lava, not water.

You can easily find the giant moon sea by looking at the western edge during a full moon. If you like searching with the best moon telescope, try the Lunar 100, searching for 100 moon surface features.

There are many questions about the moon and the interesting facts that we have answered on our site. The moon has given amateur and professional astronomers years of pleasure.