When astronomers looked at the night sky long ago, they also wondered about questions just like this one. You know, I was also curious about why the moon looks so different at different times of the month.
I visited with my friend Jose Vazquez, an astronomer at Washington State University, to learn more about it. He said that the way the moon looks to us has to do with two other objects in our solar system: our sun and earth.
Vazquez reminded me that each month the moon takes a trip around the earth. It has been making this trip for billions of years.
Let’s imagine that you had a baseball in your hand and your arm was straight out in front of you. Next, you moved your arm to the right until it was reaching out to the side.
Imagine that you let go of the ball, but it didn’t fall. Instead, it made a complete circle around you and came back to your hand. This is kind of what the moon does.