The moon takes about twenty-nine days to orbit around the earth. The sun always lights up half of the moon. We do not always see the lit-up half from the earth. When you see all the lit-up half of the moon, the moon appears to be a full circle. This is called the full moon. As the moon travels around the earth, we see less and less of the lit part. This is called the waning moon. Soon the lit-up part of the moon disappears from sight. This is called the new moon. Then the moon starts to look lit up again, and the lit part that you see gets bigger each day. This is called the waxing moon. It takes about twenty-nine days for all the phases. That’s the same amount of time it takes for the moon to make one

trip around the earth. Starting in the 1950s, spacecraft were sent to study the moon. The spacecraft orbited the moon. In this way, scientists learned more and more about the moon. Then, on July 20, 1969, the first spacecraft carrying astronauts from the earth actually landed on the moon! People were able to watch as a person walked on the moon’s surface for the first time ever.It was on television!

The astronauts sent the pictures of the moon back to the earth. The astronauts brought moon rocks back to the earth. From the rocks, scientists have learned a lot about the moon. The rocks were evidence that scientists could study to find out how the moon might have been formed. Scientists think the moon might once have been part of the earth. They think a large object from space hit the earth millions of years ago. The dust and ashes from the earth went into space and formed the moon. People have learned a lot aboutthe moon since early times!

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