In the sunny night, look up at the clear night sky. You can probably see thousands of stars. The biggest thing you’ll see, of course, is the moon. For thousands of years, people have wondered about this big thing in the sky.
Earth’s moon is a satellite. A satellite is a body that orbits(环绕轨道运行)a planet. All moons are satellites, and many planets have them. Some have many moons. Earth, of course, only has one. It’s a special moon, though. It’s the fifth largest moon in the solar system!
In fact, the moon is much smaller than the sun. But it’s much closer to Earth, so it looks as big as the sun. The moon is so close that you can see its dark and light spots(斑点)without a telescope. Men flew and landed on the moon’s surface many times by spacecrafts in the 1960s and 1970s. Neil Armstrong was the first human to step on the moon. He walked on the moon on July 20th, 1969. The flights to the moon have helped us learn much about it. Astronauts even brought rocks home with them!
There’s still a lot to learn about the moon. Now people still can’t live on the moon because it does not have oxygen or water like the Earth. But I’m sure that humans can live there one day in the future.
根据短文内容，选择最佳答案。
What is a satellite?

A．A planet.

B．A spacecraft.

C．A body that orbits a planet.

D．A black star.

How many moons does the Earth have?

A．One.	B．Four.
C．Three.	D．Two.

Why does the moon look as big as the sun?

A．Because it’s much closer to the Earth.

B．Because it comes out at night.

C．Because it is the fifth largest moon in the solar system.

D．Because people can’t see it without a telescope.

Who was the first human to walk on the moon?

A．Lance Armstrong.	B．Neil Armstrong.
C．Wally Schirra.	D．Neil Diamond.

What is this article mainly about?

A．The stars.	B．The moon.
C．The sun.	D．The earth.