How we see the Moon

If the Sun went out you would never see the Moon. The reason for this is that the Moon does not make its own light, but reflects some of the sunlight that falls on its surface to the Earth.
The amount of light that the Moon reflects depends on its position in its orbit. If all of the side of the Moon we see reflects sunlight to the Earth, we see a huge round disc called the Full Moon. If the lit side of the Moon is side on to the Earth, we see a crescent. One day a month, when the side we see gets no sunlight because it is facing away from the Sun, we cannot see the Moon at all. This is called the New Moon.


What is a moon?
It is a lump of rock which is in orbit around a planet.

Where did the Moon come from?
When the Earth was newly formed it was a huge ball of molten rock. Scientists believe that it was then hit by a planet about the size of Mars. The Earth was ripped open and became potato-shaped while chunks of molten rock were flung into space. They whirled around the Earth. Some chunks fell back to the Earth which eventually became ball-shaped again. Other chunks flew out into space while some clumped together and formed the Moon.


Can you breathe on the Moon?
No. There is no air or atmosphere. This means that there is no wind, so the astronaut's footprints will stay in the dust and will not be blown away. It also means the Moon is a silent world, because air is needed to carry sound.

How high could you jump on the Moon?
On the Earth the force of gravity holds you down. When you jump up, the force of gravity soon pulls you back.
On the Moon, the force of gravity is six times smaller than on the Earth. This means you can jump six times higher.


Do other planets have moons?
All the other planets have moons and some of the largest ones may have sixteen or more. Only Mercury and Venus do not have moons.
Why do some parts of the Moon look like grey patches?

They are made from lava which formed when the Moon was hit by huge lumps of rock from space. At first, astronomers thought the patches were made of water and called them seas. There is no liquid water on the Moon, but there is some frozen water in shady places.



Why are there circles on the Moon?

These were made by large lumps of rock crashing into the Moon. They are called craters. As there is no weather on the Moon to wear down the rocks, the craters have been there since they were formed perhaps a billion years or more ago. This means that when dinosaurs looked at the Moon they saw the same craters that you see because dinosaurs lived less than a quarter of a billion years ago.