MARY WARD CATHOLIC SECONDARY SCHOOL Centre for Self-Directed Learning Grade 9 Academic Science (SNC 1D1) Unit # 15: ASTRONOMY The Sun, the Stars, & Planets Unit Last Revised: March 2013 ACTIVITY DESCRIPTION TIME EVALUATION CATEGORY MARKS Activity A - Introduction to Astronomy 1. The Stars (in Guide) 1.5 hr Activity B Our Solar System 1. Solar System Composition 2.0 hr Activity C Reading Star Charts 1. Oh Starry Night 1.0 hr Assessment Knowledge Level Activity D - Unit Assessment 1. Hertzsprung-Russell Diagram Total Activity Time: 1.5 hr Evaluation Thinking/ Communication 6.0 hr 30 Marks Page 1 of 13
Expectations: These are the things you will be learning in this unit: Overall Demonstrate an understanding of how scientific evidence and technological advances support the development of theories about the formation, evolution, structure, and nature of our solar system and the universe; Investigate and predict the appearance and motion of visible celestial objects. Understanding Basic Concepts describe and compare the general properties and motions of the components of the solar system (e.g., the composition and the physical properties such as size and state, rotation, size and period of orbit of the Sun, planets, moons, asteroids, comets); describe the Sun and its effects on the Earth and its atmosphere (e.g., explain the importance of the Sun as an energy source and the types of radiation emitted; describe the aurora borealis); outline models and theories for describing the nature of the Sun and stars and their origin, evolution, and fate. Developing Skills of Investigation and Communication Gather, organize, and record information using a format that is appropriate to the investigation (e.g., maintain a log of observations of changes in the night sky; prepare a comparative data table on various stars); Calculate and compare the sizes of, and the distances to, objects in the solar system and in the universe beyond, using appropriate SI units. Predict the qualitative and quantitative characteristics of visible celestial objects (e.g., determine the temperature of a star by observing its colour; predict the next appearance of a comet from the time of its last appearance and the period of its orbit). Page 2 of 13
Activity A Introduction to Astronomy 1. Stars in your Investigating Science 9 textbook read pages 294 299 and answer the following questions: 1. Explain how a star is born? What is a protostar? 2. Fill in the following table: Mass Type Description Lifetime Ending Low Mass Stars Medium Mass Stars Page 3 of 13
High Mass Stars 3. What are supernovas? 4. Describe the two possible outcomes after a supernova explosion. 1. 2. Page 4 of 13
Activity B A Typical Star 2. Our Sun The sun is the largest object in our solar system. It contains more than 99.8 % of the solar system s total mass and is about 4.5 billion years old. The sun s energy output comes from nuclear fusion reactions. It is mainly composed of Hydrogen (73 %) and Helium (23 %). The rest is made up of heavier elements including carbon, oxygen, and iron. At the core of this immense star, the temperature is a whopping 15.6 million Kelvin with a remarkable pressure of 253 trillion kpa and a density of more than 150 times that of water. 1. Draw a labeled sketch of the sun in your notebook (see Figure 8.17 on Page 308) 2. Fill in the following table on the six layers of the sun: Core Radiative Zone Convective Zone Page 5 of 13
Photosphere Chromosphere Corona 3. Define the four main features on the surface of the sun below: Sunspots Prominence Solar Flares Coronal Mass Ejections 4. Describe two ways in which the sun affects our planet Earth: 1. 2. watch this cool video to see another way the sun has affected our planet: http://spaceplace.nasa.gov/violins/en/ Obtain subject teacher s signature to check your notes teacher signature: Page 6 of 13
Activity B Our Solar System 3. The Composition of our Solar System After the Sun formed, the leftover dust, gases, and other debris in the nebula continued to spin, creating a disk around the new star. Small bodies began to form, growing into the planets, moons, asteroids, and comets that make up the solar system. The next largest body bodies in the solar system are the eight planets. A planet is a celestial object that orbits one or more stars and is capable of forming into a spherical shape as t melds under the weight of its own gravity. A planet does not create and radiate its own light like a star does. It only reflects the light of the star or stars that it orbits. learn more about the planets through this interactive computer game: http://spaceplace.nasa.gov/solar-system-explorer/en/ record your highest score here: in your Investigating Science 9 textbook read pages 314-318. create a table in your notebook of the inner and outer planets (focus on the temperature, luminosity, and size). Obtain subject teacher s signature to check your table teacher signature: Page 7 of 13
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Activity C Oh Starry Night 3. Reading Star Charts Hand in for Level Assessment K/U Star charts are maps that show some or all of the 88 constellations and key stars that are visible from Earth. Stargazers use star charts to orient themselves in the night sky. The purpose of this activity will be to use the star chart (Page 551 of your textbook) to determine the location and appearance of well known stars, constellations, and asterisms visible in the northern hemisphere. Please answer the following questions and submit to your subject teacher for assessment. 1. In which constellation is Polaris (the North Star) located? 2. What planet is shown in the constellation Capricornus? 3. Betelgeuse is a large star located in what constellation? 4. What is the name of the constellation that has three bright stars in a row? 5. What is the name of the star that seems to form the tail of the swan-shaped constellation known as Cygnus? 6. Is the star Aldebaran located east or west of Betelgeuse? 7. What is the name of the star cluster located mid-way between the constellations of Taurus and Perseus? 8. What large star seems to form the right foot of the constellation commonly referred to as Orion the Hunter? Page 9 of 13
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Activity D The Size & Mass of Stars 4. The Hertzsprung-Russell Diagram Hand in for Evaluation: /30 Marks T/C Using pages 300-301 in your Investigating Science 9 textbook, draw a labeled Hertzsprung diagram below: (7 Marks) Answer the following questions below: 1. Where did the Hertzsprung-Russell diagram come from? Why is it significant? (2 Marks) Page 11 of 13
2. How are the stars arranged in the diagram? (3 Marks) 3. What is wrong with stars that do not appear along the main sequence? (1 Mark) 4. What will eventually happen to white dwarfs? Red giants? (2 Marks) 5. According to the diagram, which star s surface temperature is cooler, Antares or Vega? (1 Mark) 6. How many times more luminous is Porlaris than Procyon A? (2 Marks) 7. The sun is too low a mass to explode into a supernova. As the sun evolves and slowly dies out, on which part of the diagram would it be classified? (2 Marks) Page 12 of 13
8. State the color of each of the following stars: (3 Marks) i) Rigel - ii) the Sun - iii) Aldebaran - 9. How many times brighter than the Sun is Betelgeuse? (2 Marks) 10. What is the surface temperature of Procyon? (1 Mark) 11. Which stars have a higher surface temperature: Yellow or Red? Why? (2 Marks) 12. Red stars normally have low luminosity. Explain how a red star such as Betelgeuse can be one of the brightest stars in the sky. (2 Marks) Page 13 of 13