To spin is to __________.

To travel around an object is to ________________.

The path an object follows as it revolves is called its _______________.

The imaginary (or real) line an object spins around is called its _______.

Earth's axis is _________.

Earth's seasons are caused by what?

The Earth revolves around the ____.

The Moon revolves around the ___.

Which is the largest?

Which is the smallest?

What is the phase of the moon when it looks like a big circle in the sky?

What is the phase of the moon called when it is almost full?

What is the phase of them moon called when we can't see it at all?

What is the phase of the moon called when we just see a little sliver?

In ancient times, scientists relied on what they could observe. Aristotle, an ancient Greek astronomer, saw the motion of the Moon, Sun, and Stars. He concluded that ___.

Ptolemy was an ancient Egyptian astronomer who also believed in an Earth-centered model. This meant the Earth was round and unmoving as the Sun and other heavenly bodies ___.

Copernicus, a Polish astronomer, had a new theory. As a scientist, he hypothesized that ____ was the center of the solar system and that the Earth and other planets revolved around it.

Galileo, an Italian astronomer, developed and improved the telescope. He was able to see, for the first time, clear evidence that the _____ was correct.

The distance between which of these is the shortest?

The United States Apollo Space Program to put a man on the moon was run by ___.

July 20, 1969, astronauts Neil Armstrong and Edwin "Buzz" Aldrin were the ____ people to walk on the moon.

Astronauts brought back moon ____ to help scientists here on Earth study the moon's composition.