Earth-Moon-Sun System Study Guide
Sun
1. The sun is made of burning gases.
2. The sun is the center of our solar system and its gravitational pull
keeps the Earth from shooting off into space.
3. The sun is a bright, medium sized-star.
Moon
1.
2.
3.
4.
The moon orbits the Earth.
The moon is the Earth’s only natural satellite.
The moon’s orbit, or cycle, lasts 28 days.
The moon does not change its shape. The phases of the moon are
caused by the position of the moon and its relation to the sun.
These are called the moon’s phases. The order of the moon’s
phases are new moon, waxing crescent, first quarter, waxing
gibbous, full moon, waning gibbous, last (third) quarter, and waning
crescent.
5. The moon reflects sunlight.
Earth
1.
2.
3.
4.
The Earth orbits the sun.
The Earth completes one revolution in about 365 days.
The Earth completes one rotation in 24 hours.
The Earth tilts on its axis. This causes seasons.
Historical Contributions
1. There are two scientific views on our solar system.
2. Geocentric – the Earth is the center of our solar system and it all of
the planets, and the sun, revolves around it.
3. Aristotle, a Greek philosopher, and Ptolemy, a Greek astronomer
who worked in Egypt, believed in the Geocentric view.
4. Heliocentric – the Sun is the center of our solar system and all of the
planets revolve around it.
5. Copernicus, a Polish scientist, believed in this view. He thought
the sun was the center of the universe.
6. Galileo, an Italian astronomer, also believed that the sun was the
center of the universe. He built a better version of the telescope
that allowed him to see farther into the sky.
7. He discovered planets and moons and was arrested for his
statements because the church did not believe his findings.
8. NASA is the national space program today.
9. NASA has sent men to the moon. Just recently, NASA discovered
water on the moon.
Vocabulary
1. Satellite – an object that moves around another object in space.
2. Orbit – a path an object takes around another object.
3. Revolution – the time it takes a satellite to make one complete orbit
(the Earth completes one revolution in about 365 days)
4. Axis – an imaginary line that runs through the center of Earth from
the North Pole to the South Pole
5. Rotation – the time it takes a body to spin one time on its axis (the
Earth completes one rotation in 24 hours)
6. Tilt – the Earth’s tilt on its axis causes seasons.