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Patterns on 4.8C Have you ever made shadow puppets? If you put your hand between a flashlight and a wall, you will make a shadow. You might have made a shape or some other animal shape with your hands. Your hand blocks the from the flashlight.

The shines on Earth like a giant flashlight. Light from the Sun causes shadows that we can see here on Earth. The angle of the Sun’s light also causes the change in : from to to to fall. How else does Earth interact with the Sun?

What time of day do you think it is in the first picture? What time of day do you think it is in the picture? Explain your answers.

Patterns on Earth 4.8C Take a few to collect and analyze data in order to predict seasonal changes in your area. A change in temperature is one way to show that a new season is coming. As a scientist, your job is to collect data to predict patterns of change in things over time, like seasons. Go online and locate the high and low temperatures in your area for each for the last three . When did each season occur? How can you tell? Analyze these data and see if you can find a pattern. Use this information to predict the time of the next season change in your area.

You may think that seasons happen because Earth is farther away from the Sun in winter or closer to the Sun in summer. This is not correct. Earth stays at almost the same distance from the Sun all . Seasons happen because Earth is tilted on its axis. During summer, the northern part of Earth is tilted toward the Sun. The Sun’s light hits the northern part of Earth more directly. The heat from the sunlight causes the warm of summer. During winter, the northern part of Earth is tilted, or leaning away from the Sun. The Sun’s light does not shine as directly, causing cooler weather.

How do the positions of Earth and the affect tides on Earth? If you stand on a beach for several , you will see the tide coming in and out. The tide is the rise and fall of water over a period of time. Tides rise and fall every day—sometimes even twice a day. But what causes tides?

Look up into the sky and you might see the Moon. The Moon Earth. This means that the Moon moves around Earth in a path shaped like a circle. gravity: the force that The Moon and Earth pull on each attracts one thing with other due to gravity. When the Moon mass to another thing pulls on Earth, the solid parts of Earth with mass stay in place. They cannot move very much. But the water in the can move more easily. The Moon’s gravity pulls the ocean water toward it. This causes a bulge in the ocean in the direction of the Moon. This bulge is what causes a high tide. Ocean water comes up higher on a shoreline as it is pulled toward the Moon. As the ocean is pulled toward the Moon, it causes a low tide in another part of Earth.

Patterns on Earth 4.8C How does the Moon’s appearance in the sky change? We are able to see the Moon because it reflects light from the Sun. Have you noticed how the Moon’s shape changes during the month? The Moon seems to get bigger, and then it seems to get smaller. Sometimes, it seems to disappear completely. These changes happen in the same pattern each month. In fact, you : the circular can predict them! The Sun always shines on half of the Moon. But path of one object around another object on Earth, we cannot always see the sunlit half. This is because the Moon moves around Earth in an orbit. At the beginning of each month, we cannot see the Moon at all. The sunlit half of the Moon faces away from Earth. Each night we see more of the Moon. After about two , we can see the entire sunlit half of the Moon. Then, the Moon seems to get smaller again. Each night we see less and less. At the end of the month, we cannot see the Moon at all again. The pattern then repeats itself.

As the Moon orbits Earth, we see different parts of it. At the beginning and end of each month, we see very little of the Moon. Midway through each month, we see a large part of the Moon.

Patterns on Earth 4.8C

Discover : Ancient Cultures have noticed patterns on Earth for a very long time. For example, ancient Romans used to tell time. The Romans noticed that the length and shape of shadows changed over the course of a day. They built sundials to allow them to keep track of the hours in a day.

Ancient Chinese people used the Moon’s changing appearance to make a . Each month was 29 days—the amount of time it takes the Moon to orbit Earth. The beginning of a month was marked by a new moon. This calendar is still used to keep track of Chinese holidays.

What Do You Know? The Moon, Earth, and Sun interact in many different ways. That means they affect each other, or cause changes to each other. These interactions cause patterns on Earth that we can predict. The graphic organizer below describes some of these patterns. It is missing some information. Use the words in the box below to fill in the missing parts of the graphic organizer: