1 / 29

Section 3 Mapping the Stars

Chapter J1. Section 3 Mapping the Stars. Objectives. Explain how constellations are used to organize the night sky. Describe how the altitude of a star is measured. Explain how the celestial sphere is used to describe the location of objects in the sky.

fmedina
Download Presentation

Section 3 Mapping the Stars

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter J1 Section 3Mapping the Stars Objectives • Explain how constellations are used to organize the night sky. • Describe how the altitude of a star is measured. • Explain how the celestial sphere is used to describe the location of objects in the sky. • Compare size and scale in the universe, and explain how red shift indicates that the universe is expanding.

  2. Chapter J1 Section 3Mapping the Stars Patterns in the Sky • Constellations Help Organize the Sky A constellation is a region of the sky. Each constellation shares a border with neighboring constellations. • Seasonal Changes As Earth revolves around the sun, the apparent locations of the constellations change from season to season.

  3. Chapter J1 Section 3Mapping the Stars Spring Constellations in the Northern Hemisphere

  4. Chapter J1 Section 3Mapping the Stars Finding Stars in the Night Sky • You can describe the location of a star or planet by using an instrument called an astrolabe and the following points of reference: • Thezenithis the point in the sky directly above on observer on Earth. • Thealtitudeis the angle between an object in the sky and the horizon. • Thehorizonis the line where the sky and the Earth appear to meet.

  5. Chapter J1 Section 3Mapping the Stars Zenith, Altitude, and Horizon

  6. Chapter J1 Section 3Mapping the Stars Finding Stars in the Night Sky, continued • Using an astrolabe allows you to describe where a star or planet is relative to you. Scientists need a different method that describes location independently of the observer’s location. • Astronomers describe the location of a star or planet in terms of the celestial sphere.

  7. Chapter J1 Section 3Mapping the Stars The Celestial Sphere

  8. Chapter J1 Section 3Mapping the Stars Describing a Star’s Position Click below to watch the Visual Concept. You may stop the video at any time by pressing the Esc key. Visual Concept

  9. Chapter J1 Section 3Mapping the Stars The Size and Scale of the Universe • In the 1600s, Nicolaus Copernicus noticed that the planets appeared to move relative to each other but that the stars did not. Thus, he thought that the stars must be much farther away than the planets. • Measuring Distance in SpaceA light-year is a unit of length equal to the distance that light travels in 1 year.

  10. Chapter J1 Section 3Mapping the Stars The Size and Scale of the Universe, continued • It is important to consider scale when thinking about the universe. Although stars looks tiny in the night sky, remember that they are actually a lot larger than Earth.

  11. Chapter J1 Section 3Mapping the Stars The Doppler Effect • What Is the Doppler Effect?Have you ever noticed that when a driver in an approaching car blows the horn, the horn sounds higher pitched as the car approaches and lower pitched after the car passes? This effect is called the Doppler effect. • An Expanding UniverseThe Doppler effect has been used to discover that galaxies are rapidly moving apart from each other.

  12. Chapter J1 Section 3Mapping the Stars Red Shift Click below to watch the Visual Concept. You may stop the video at any time by pressing the Esc key. Visual Concept

  13. Standardized Test Preparation Chapter J1 Reading Read each of the passages. Then, answer the questions that follow each passage.

  14. Standardized Test Preparation Chapter J1 2. Why don’t upright objects cast a shadow when the sun is at its zenith? F because the sun is directly overhead G because the summer solstice is occurring H because the sun is below the horizon I because the sun is at its zenith on the longest day of the year

  15. Standardized Test Preparation Chapter J1 INTERPRETING GRAPHICS The diagram on the following slide shows a galaxy moving in relation to four observers. The concentric circles illustrate the Doppler effect at each location. Use the diagram to answer the questions that follow.

  16. Standardized Test Preparation Chapter J1

  17. Standardized Test Preparation Chapter J1 1. Which of the following observers would see the light from the galaxy affected by redshift? A observers 1 and 2 B observer 3 C observers 3 and 4 D observers 1 and 4

  18. Standardized Test Preparation Chapter J1 1. Which of the following observers would see the light from the galaxy affected by redshift? A observers 1 and 2 B observer 3 C observers 3 and 4 D observers 1 and 4

  19. Standardized Test Preparation Chapter J1 2. Which of the following observers would see the light from the galaxy affected by blueshift? F observer 1 G observers 2 and 4 H observers 3 and 4 I observer 2

  20. Standardized Test Preparation Chapter J1 2. Which of the following observers would see the light from the galaxy affected by blueshift? F observer 1 G observers 2 and 4 H observers 3 and 4 I observer 2

  21. Standardized Test Preparation Chapter J1 3. How would the wavelengths of light detected by observer 4 appear? A The wavelengths would appear shorter than they really are. B The wavelengths would appear longer than they really are. C The wavelengths would appear unchanged. D The wavelengths would alternate between blue and red.

  22. Standardized Test Preparation Chapter J1 3. How would the wavelengths of light detected by observer 4 appear? A The wavelengths would appear shorter than they really are. B The wavelengths would appear longer than they really are. C The wavelengths would appear unchanged. D The wavelengths would alternate between blue and red.

  23. Standardized Test Preparation Chapter J1 MATH Read each of the following questions, and choose the best answer.

  24. Standardized Test Preparation Chapter J1 1. If light travels 300,000 km/s, how long does light reflected from Mars take to reach Earth when Mars is 65,000,000 km away? A 22 s B 217 s C 2,170 s D 2,200 s

  25. Standardized Test Preparation Chapter J1 1. If light travels 300,000 km/s, how long does light reflected from Mars take to reach Earth when Mars is 65,000,000 km away? A 22 s B 217 s C 2,170 s D 2,200 s

  26. Standardized Test Preparation Chapter J1 4. If the altitude of a star is 37°, what is the angle between the star and the zenith? F 143° G 90° H 53° I 37°

  27. Standardized Test Preparation Chapter J1 4. If the altitude of a star is 37°, what is the angle between the star and the zenith? F 143° G 90° H 53° I 37°

  28. Standardized Test Preparation Chapter J1 5. You are studying an image made by the Hubble Space Telescope. If you observe 90 stars in an area that is 1 cm2 , which of the following estimates is the best estimate for the number of stars in 15 cm2 ? A 700 B 900 C 1,200 D 1,350

  29. Standardized Test Preparation Chapter J1 5. You are studying an image made by the Hubble Space Telescope. If you observe 90 stars in an area that is 1 cm2 , which of the following estimates is the best estimate for the number of stars in 15 cm2 ? A 700 B 900 C 1,200 D 1,350

More Related