Transcript Space 1.4
Before, you learned • Light and other radiation carry information about space • Astronauts explore space near Earth Now, you will learn • How space exploration has helped us to learn more about Earth • How space technology is used on Earth VOCABULARY impact crater Magnet Word Diagram = Include: definition, example(s), picture, pronounce, origin, sentence. Space exploration has given us new viewpoints. Space exploration enriches us in many ways. Throughout history, the study of stars and planets has inspired new ideas. As we meet the challenges of space exploration, we gain valuable technology. Space exploration is also an exciting adventure. Space science has advanced knowledge in other scientific fields, such as physics. For example, observations of the Moon and other bodies in space helped scientists understand how gravity works. Scientists figured out that the same force that causes an object to fall to the ground causes the Moon to orbit Earth. Finally, the study of other worlds can teach us about our own. Earth has changed considerably since its formation. By comparing Earth with different worlds, scientists can learn more about the history of Earth's surface features and atmosphere. Identify some benefits of space exploration. Space Exploration Benefits Link Surface Features Exploration of other worlds has helped us learn about the impacts of space objects. When an object strikes the surface of a larger object in space, it explodes and leaves behind a round pit called an impact crater. The previous illustration shows how an impact crater forms. Earth has little evidence of impacts because its surface is constantly being worn down by wind and water and altered by forces beneath the surface. However, impact craters remain on the Moon, Mercury, and many other bodies that have no wind or liquid water. Atmosphere We are also learning about Earth's atmosphere from space exploration. Earth's temperature allows liquid water to remain on the surface. Mars and Venus, the planets closest to Earth, have no liquid water on their surfaces. By comparing Earth with those planets, we can see how liquid water has affected the development of Earth's atmosphere. Another area of study involves the energy Earth receives from the Sun. Many scientists think that small changes visible on the Sun's surface can affect weather on Earth. These changes may have caused periods of cooling in Earth's atmosphere. What have scientists learned about Earth's past from studying bodies in space? How does meteorite speed affect the size of an impact crater? Procedures: 1. Fill plastic tub 2 cm deep w/ white calcite. Add another 2 cm layer of sand on top of the white calcite, and smooth surface with a ruler. 2. Create 2 craters by dropping the weighted ball into the sand from a height of 35 cm. Sketch, measure, and label/record each crater. 3. Repeat steps 1 and 2, dropping the weighted ball from 35 cm, this time add force. Be sure to release at 35 cm. Sketch, measure, and label/record each crater. Materials: Plastic tub, white calcite, sand, rulers, weighted ball Data: Sketches of crater impacts w/ appropriate labels. 35 cm 35 cm + force 35 cm 35 cm + force WDUT: • How did the craters differ when the weighted ball was dropped at different speeds? • What’s a new question you have from conducting this experiment? • What natural processes besides weather can affect evidence of impacts from space objects on Earth? Space technology has practical uses. Space exploration has done more than increase our knowledge. It has also provided us with technology that makes life on Earth easier. Each day you probably benefit from some material or product that was developed for the space program. Satellite Views of Earth One of the most important benefits of space exploration has been the development of satellite technology. Satellites collect data from every region of our planet. The data are sent to receivers on Earth and converted into images. Scientists have learned from the space program how to enhance such images to gain more information. Weather satellites show conditions throughout Earth's atmosphere. Images and data from weather satellites have greatly improved weather forecasting. Scientists can now provide warnings of dangerous storms long before they strike populated areas. Other satellites collect images of Earth's surface to show how it is being changed by natural events and human activity. Satellite data are also used for wildlife preservation, conservation of natural resources, and mapping. Technology Spinoffs Have you ever come up with a new way to use something that was designed for a different purpose? NASA often creates advanced technology to meet the special demands of space travel. Many spinoffs of technology from the space program can be found in homes, offices, schools, and hospitals. Everything on a spacecraft must be as small and lightweight as possible because the heavier a spacecraft is, the more difficult it is to launch. Design techniques developed to meet this need have improved devices used on Earth, such as tools for diagnosing diseases and devices that help people overcome disabilities. Materials and parts on a spacecraft have to endure harsh conditions, such as extreme heat and cold. Many new homes and buildings contain fire-resistant materials developed for the space program. Firefighters wear protective suits made from fabric originally used in space suits. NASA has also helped design devices that allow firefighters to avoid injury from inhaling smoke. Humans need a safe environment in spacecraft and space stations. NASA has developed systems for purifying air, water, and food. These systems now help protect people on Earth as well as in space. KEY CONCEPTS 1. How has space exploration helped us learn about impacts of space objects on Earth? 2. How do satellites provide images of Earth's surface and atmosphere? 3. Give two examples of technology we use on Earth that is a result of space exploration. CRITICAL THINKING 4. Infer Hurricanes form in the middle of the ocean. Why would satellites be useful in tracking hurricanes? 5. Apply What space-technology spinoffs might be used in a school? CHALLENGE 6. Predict It takes over a year for a spacecraft to reach Mars and return to Earth. If astronauts ever travel to Mars, they will need a spacecraft that can recycle air and water. How might such technology be adapted for use on Earth?