the moon
TRANSCRIPT
What is known about the moon?
Chapter7 Lesson 4
Motions of the Moon
The moon is the Earth’s closest neighbor.The moon revolves around Earth while Earth revolves around the sun.
The moon takes about27 days to complete one revolution around Earth. The moon also rotates on its axis about once every 27 days.Because these two motions happen at the same rate,
the same side of the moon always faces Earth.
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The moon is the brightest object in the night sky. But the moon does not make light. It reflects light from the sun. Moon shining = reflected sunlight
Half of the moon is always lit by the sun. But the moon’s lit half cannot always be seen from Earth.Everyday, we can see different parts of the sunlit half. These changes are caused by the movements of Earth and the moon in their orbits.
Moon phase is the shape the moon seems to have at a given time.
The moon’s phases change in a cycle that repeats every29½ days
New moon is when none of the moon appears lit (no part of the moon’s lit half is visible.
First quarter phase is when the moon looks like a half circle a week after the new moon .
Full moon phase is when the moon happens about two weeks after the new moon. You see all of the lit half of the moon.(the moon looks like a complete circle(
Third quarter phase is when three-fourths of the moon’s cycle is complete. In a week, you see less and less of the moon’s lit half. Then there is a new moon
Characteristics of the Moon
1-The moon is the closest natural object to Earth. It is 384000 kilometers (239000 miles) away.
2-The moon is smaller and has much less mass than Earth. In fact, Earth’s volume is 49 times greater than the moon’s volume.Earth has 81 times more mass.
The moon’s surface has many craters.Crater is a bowl-shaped hole on the surface of an object in space.
Most of the moon’s craters formed when large objects, such as asteroids, smashed into the moon.
When you look at the moon, you see that there are light and dark areas on it.
The light areas are mountains and highlands.There are many craters in these areas.
The dark parts of the moon are flat areas with some craters.
Billions of years ago, volcanoes erupted on the moon.Lava from these eruptions spread out and hardened. It formed the dark areas.
The temperature on the moon’s surface varies. During the day, the temperature can rise as high as 127C (260F).At night, it can get as cold as -173C (-280F(
Telescopes
Telescope makes objects that are far away look like they are nearer and larger.You can use a telescope to see more details of the light and dark areas on the moon’s surface.
People have used spacecrafts to put telescopes in outer space.The Hubble Space Telescope began orbiting Earth in 1990.
scientists use it to observe and take pictures of plants, stars, moons, and other space objects.