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The Moon: vocabulary; All About the Moon 2


Read the passage, then answer the practice question.

All About the Moon

Picture 1: the moon
  1. Do you ever look up at the night sky and wonder about the moon? From Earth, it can look unreal. What is it made of? Why does it glow in the sky? Why does it seem to change shape? People have been wondering about the moon for thousands of years. Today, we know a lot about the moon.
  2. The moon is made up of rock. If you walked on the moon’s surface, you would see that the first layer is like thick dust. Your boot would sink into the dust a bit and leave a print. Because there is no wind on the moon, these prints will not disappear. The footsteps of the first person to walk on the moon are still there many years later. Under this first layer of dust is hard rock. The center part of the moon is called the core, and it is made of iron.
Picture 2: a person walking on the moon
  1. The moon has many round holes on its surface. These craters form when giant space rocks—called asteroids and meteorites—smash into the moon. Some of the craters on the moon have been there for thousands of years, and some are new.
  2. The moon also has mountains, and areas known as “seas”. These “seas” are not like the seas we have on Earth, which are made of water. Instead, the moon’s seas are made of lava that has hardened into rock. A very long time ago, when the moon was new, it had volcanoes. When they erupted, lava flowed over the moon’s surface and hardened. This is how the moon’s “seas” were formed. From Earth, the moon’s “seas” look like dark, circular pools.
Picture 3: a drawing of the moon’s phases
  1. Although many people think that the moon makes its own light, it doesn’t. This is a misunderstanding. The moon’s glow is actually caused by light reflected from the sun. As the moon orbits the earth, it looks like it changes shape. Actually, the sun is lighting up different parts of the moon while the earth creates shadows. These different shapes tell us where the moon is in its path around the earth. They are called “phases”. That is why the moon sometimes looks like a circle and sometimes looks like a sliver, or crescent.

Practice question

Read this sentence from paragraph 2.
“Because there is no wind on the moon, these prints will not disappear.”
As it’s used in this sentence, the word prints means