UC Irvine FOCUS! 5 E Lesson Plan

UC Irvine FOCUS! 5 E Lesson Plan Title: Astronomical Units and The Solar System Grade Level and Course: 8th grade Physical Science Materials: Visual introduction for solar system (slides, video, posters, etc) Materials for TPR Solar System, including about 560 m (1800 feet) of heavy string or rope, meter sticks, colored markers to illustrate planets on paper Student lab with planetary data and worksheets Instructional Resources Used: (concept maps, websites, think-pair-share, video clips, random selection of students etc.) PowerPoint slide show of planets Student access to information about planets/solar system (eg: text) Numerous solar system animated video tours exist on the web. Many are short, entertaining, and very appropriate for middle school students. A classic video showing relative distances is Powers of 10 by Charles and James Eames, is also available on line originally released in the 1970 s, it s still well worth watching today! Web sites, such as Nineplanets.org offer abundant images and information on current astronomical research and NASA robotic missions Think-pair-share, sentence frames, Venn diagrams California State Standards: (written out) 8.4c. Students know how to use astronomical units and light years as measures of distances between the Sun, stars, and Earth 8.4e. Students know the appearance, general composition, relative position and size, and motion of objects in the solar system, including planets, planetary satellites, comets, and asteroids. Common Core State Standards: (written out) Lesson Objectives: Students will understand how to use Astronomical Units for measuring distances within the solar system Students will graph the relationship between Astronomical units and orbital periods by the planets Students will distinguish between the eight planets and three dwarf planets as recently (2006) catalogued by the International Astronomical Union (IAU) Differentiation Strategies to meet the needs of diverse learners: English learners a. Among the resources available on-line are video presentations at all

levels of depth and vocabulary. Animations with vocabulary/content depth more appropriate for EL students are readily available. This site, http://www.neok12.com/solar-system.htm has several short, yet interesting, videos on the planets and solar system. b. EL students should be partnered with bi-lingual students. Students will participate in Think-pair-share and sharing comments as part of a class discussion. EL students will answer questions in complete sentences from sentence frames and/or sentence starters. c. Teacher should model completing the grid for Activity 1 and Activity 3. Special Education: a. The Activity 1 portion of the worksheet should be modified and perhaps turned into a separate page. Perhaps spaces below the grid could be provided for student to write the names of planets b. A more thorough discussion of what is meant by scale should precede the Activity 2 TPR, as well as making sure students know how to measure an extended distance outdoors with a meter stick GATE: a. Further discussion about the relationship between a planet s distance from the sun and its orbital period could include (1) Newton s Inverse-square law (2) Newton s law of universal gravitation (3) Kepler s laws of planetary motion b. The creation of a dwarf planet category and re-classification of Pluto in 2006 is an excellent opportunity to discuss the nature of science. As new information emerges, science is sometimes forced to re-think its position on a topic. This means our understanding of nature may change over time; older models become outdated, newer models take their place! ENGAGE Invite students to tell what they know about the planets. Are students aware of the reclassification of Pluto as a dwarf planet? Introduce the solar system with PowerPoint slides or video presentation EXPLORE Using a chart of Astronomical Units, students use graph paper strip to show the relative distances of the planets (1/8 inch = 1 AU) (Activity 1) Students use lengths of rope to represent the relative distances as on outdoor TPR (1 meter = 1 AU) (Activity 2) Students compare the distance a planet is from the sun with its revolution period (Activity 3) EXPLAIN What s the Big Idea? Understanding the frequency and general characteristics of our solar system s planets, dwarf planets, and moons and asteroids, and the use of the Astronomical Unit for measuring distances within the solar system Higher Order questions presented to students

(1) Describe the similarities and differences of inner and outer planets (2) Describe the occurrence of moons in our solar system (3) What is the relationship between a planet s distance from the sun and it s orbital period around the sun? (4) What is the difference between a light year and an astronomical unit and when should each be used? (5) Why was Pluto changed to the dwarf planet designation? EXTEND Students can explore a web site such as Nineplanets.org to: a. Describe physical details of solar system bodies b. Compare and contrast inner and outer planets, asteroids and comets, or earth and other bodies (moons, terrestrial planets) in the solar system c. Research robotic missions (such as Voyager which imaged the four gas giant planets) and what we have learned from them. Students can research a particular solar system body and generate a presentation, such as PowerPoint, poster, or oral report. Students can make a model of the solar system. Styrofoam ball models are seldom to scale, but can be a fun and creative project. When several are hung from the ceiling, they make impressive additions to a fun classroom! Teacher should reinforce the relationship between light years and astronomical units. (1) Light year: used for measuring distances among stars / galaxies (2) Astronomical Unit (AU): used for measuring distance within the solar system Discuss with students that our chart and outdoor model of the solar system only show relative distances between the planets, and was the focus of this lesson. Sources are available, such as the pinhead solar system that incorporate the relative size of the planets as well. Directions are available on-line for using dry ice to model a comet as a teacher demonstration. Any time dry ice is involved, you will have the students rapt attention! (1) The icy nature of a comet will be easily imprinted on students (2) The sublimating fog from the dry ice is an excellent model of a comet s tail. Putting a piece of dry ice in warm water dramatically increases the fog effect, highlighting the growing tale as a comet nears the sun! Background Knowledge for the Teacher: Illustrations of our solar system are often misleading. They usually give a sense that the planets are equi-distance apart from each other. This is unfortunate, but necessary, to fit all the planets in one picture. In reality, the inner planets (Mercury, Venus, Earth, Mars) or terrestrial planets, are relatively close together nearer the sun. The outer planets (Jupiter, Saturn, Uranus, Neptune) or gas giant planets are much farther away and much farther apart from each other than we usually see in the pictures. In 2006, the International Astronomical Union (IAU) created the dwarf planet designation. The IAU included the largest asteroid Ceres and the newly discovered Eris. It also re-designated Pluto as a dwarf planet. There

are other candidates being considered for dwarf planets, and it is expected that there may be hundreds such bodies awaiting discovery! The orbital period of the planets is exponentially longer as distance from the sun increases. The slower orbits of the outer planets are partly due to the longer distance the planet must travel around the sun. But more significant is the exponentially weaker gravitational attraction of the sun on the planet, requiring a much slower speed of the planet to maintain a stable orbit around the sun. NASA robotic missions have been generally very successful. Highlighting some of these missions, such as the Viking or Pathfinder missions to Mars in the 1970 s, adds an exciting component to the class discussions. It brings in the highly motivating elements of rockets and space travel. It also accents the healthy integration of science and engineering.

Student Name Date The AMAZING Solar System! Today Our Solar System Consists of Our Sun! The Center of our Solar System! Eight planets that orbit the sun Three dwarf planets that also orbit the sun Over 150 moons that orbit the planets Countless asteroids, many in the asteroid belt Icy comets in highly elliptical orbits An Astronomical Unit is a convenient way to measure distances in the solar system. It is the average distance from the earth to the sun, about 150 million kilometers (93 million miles) In 2006, the International Astronomical Union (IAU) met in Europe and created a new class of heavenly body, the dwarf planet. It included three objects in this new category Ceres, the largest asteroid in the asteroid belt Pluto, traditionally the ninth planet Eris, discovered in 2005 and is larger than Pluto The Revolution Period is the time is takes for the object to orbit the sun. Planet/Dwarf Planet Distance in AU Revolution Period Mercury.4 AU.2 Year Venus.7 AU.6 Year Earth 1.0 AU 1.0 Year Mars 1.5 AU 1.9 Years Ceres (Asteroid Belt) 2.8 AU 4.6 Years Jupiter 5.2 AU 11.9 Years Saturn 9.5 AU 29.5 Years Uranus 20.0 AU 84 Years Neptune 30.0 AU 165 Years Pluto (Dwarf Planet) 40.0 AU 248 Years Eris (Dwarf Planet) 50.0 AU 555 Years

Activity 1 Plot the Dots! Mark the Center Line to Show Where Each Planet Would Be! 1. Use the data above to show distances of the planets/dwarf planets from sun. 2. Label above the chart, Astronomical Units and number 0-40. 3. Make a dot along the line to show each objects average distance from the sun 4. Label each dot with a line pointing to the name underneath the chart AU = Label Activity 2 1. The teacher will set up a long length of rope outside the classroom 2. Work with partner(s) to make 8 ½ x 11 illustrations. Your teacher will assign the picture for your group, including sun, planets, earth s moon and dwarf planets 3. Using the scale, 1 meter = 1 AU, calculate how far your object is from the sun 4. Take your illustration outside to model the Astronomical Unit distances. Use a meter stick to find where your object will be along the rope, then stand there! a. The sun is at one end of the string b. Each group measures how far away from the sun they should be 5. Before disassembling your model, look closely at the relative distances represented by where students are standing compared to the sun and each other! Summarize what you noticed about the distances of planets in the two activities What do you notice about the first four planets? What do you notice about the last four planets?

Activity 3 How does the distance from the sun affect the planets orbit around the sun? Use the chart on the first page to compare the planet s distance and revolution. 1. List the planets/dwarf planets in order along the bottom of the graph 2. Label the top of the graph, Solar System Object Orbit the Sun 3. Label the side of the graph years and number the graph by 20 s 4. Construct a bar graph to compare the length of each object s revolution

Summarize what you noticed about the revolution of planets in the above graph Why do you think the closer planets revolve faster than the outer planets? Further Review 1. How many kilometers is an astronomical unit? 2. Why was this number selected? 3. Why is using astronomical units easier than using kilometers or miles for measuring distances in the solar system? 4. Why do you think we use astronomical units for measuring distances to the planets, but light years for measuring distances to the other stars? 5. Using the chart on the first page, calculate the distances in Astronomical Units a. the distance from Earth to the sun b. the distance from the sun to Neptune c. the distance from Earth to Mars d. the distance from Earth to Pluto e. the distance from Jupiter to Saturn f. the distance from Earth to Ceres g. the distance from Pluto to Eris 6. How far would a round-trip be in Astronomical Units a. from Earth to Mars and back b. from Earth to Mercury and back c. from Earth to Saturn and back d. from Earth to Pluto and back