Ka Hana Imi Na auao A Science Careers Curriculum Resource Project Available at: 4

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1 SC/ES/PS.6 Standard 6: Physical, Earth, and Space Sciences: NATURE OF MATTER AND ENERGY: Understand the nature of matter and energy, forms of energy (including waves) and energy transformations, and their significance in understanding the structure of the universe; SC.PS.6.12 Describe nuclear reactions and how they produce energy; SC/ES/PS.7 Standard 7: Physical, Earth, and Space Sciences: FORCE AND MOTION: Understand the relationship between force, mass, and motion of objects; and know the major natural forces; gravitational, electric, and magnetic; SC.PS.7.2 Use vectors to explain force and motion; SC.PS.7.3 Explain the relationship among the gravitational force, the mass of the objects, and the distance between objects; SC.PS.7.4 Explain the magnetic and electric forces in the universe; SC.ES.8 Standard 8: Physical, Earth, and Space Sciences: EARTH AND SPACE SCIENCE: Understand the Earth and its processes, the solar system, and the universe and its contents; SC.ES.8.4 Describe how heat and energy transfer into and out of the atmosphere and their involvement in global climate; SC.ES.8.8 Describe the major internal and external sources of energy on Earth; SC.ES.8.10 Compare different theories concerning the formation of the universe; SC Explain that every object has mass and therefore exerts a gravitational force on other objects: SC Describe the composition of objects in the galaxy; SC Compare the characteristics and movement patterns of the planets in our solar system; SC Describe the major components of the universe; SC Describe the role of gravitational force in the motions of planetary systems; SC Recognize changes that indicate that a chemical reaction has taken place; SC Describe the relationship (size and distance) of Earth to other components in the solar system; SC Describe examples of what astronomers have discovered using telescopes; SC Explain that the planets orbit the sun and that the moon orbits the Earth; SC Describe that the mass of the Earth exerts a gravitational force on all objects Source: See Introduction section or go to: Career/Technical Education Standards/HCPS III related to this item: CTE Standard 2: CAREER PLANNING: Explore and understand educational and career options in order to develop and implement personal, educational, and career goals; CTE Analyze annual individual education and career goals; CTE Evaluate potential career choices in relation to personal interests, strengths, and values; CTE Apply appropriate and safe behaviors and practices in the school, community, and workplace; CTE Assess career portfolio that documents evidence of progress toward the attainment of personal, educational, and career goals; CTE Analyze the demographic, geographic, and technological trends that affect work opportunities; CTE Gather and prepare documents related to job-seeking; CTE Prepare for the job interview process; CTE Assess the compensation, lifestyle, and other benefits associated with careers of interest Ka Hana Imi Na auao A Science Careers Curriculum Resource Project Available at: 4

2 Unit 7 Kilo Hoku - Astronomy

3 495 Ka Hana Imi Na auao A Science Careers Curriculum Resource was written and published by the Center on Disability Studies, College of Education, Univ. of Hawai i, USA. Available at: The authors permit any non-profit agency or individual to use, copy &/or alter all materials, in part or whole, for educational purposes without obtaining further consent. Note: This curriculum may be printed here in grayscale. Color versions of all documents are available on the disk found in the curriculum package, and can also be accessed online (see above). Ka Hana Imi Na auao A Science Careers Curriculum Resource Available at:

4 Ka Hana Imi Na auao A Science Careers Curriculum Resource UNIT 7: Kilo Hōkū - Astronomy & Navigation CONTENT: Hawaiian Science Careers & College MATERIALS: Student Handout /Reading Teacher s Notes Lesson ACTIVITIES: Hands On Discussion Huaka i (Explore) Web Video/Powerpt. ASSESSMENT: Formative, Summative TYPE: Individual, Group Part Content & Activity Assessment A. p Students get Origins & Inferences Making Inferences Activity: An exploration in black box inquiry (3 pgs of teacher s notes) Group Reading Activity: Wayfinding, 2 pg. handout with teacher s notes (see also Origins of Astronomy in HI, a 10 pg. reading w/ 17 pg. alternate group reading activity in Unit 7 Appendix on compact disk) Mini-Lab: Looking for Life in the Solar System Readings & Discussion: Life in the Universe Space Rocks (2 pgs, no notes given) Field Trip: Join amateur astronomy group for evening observation &/or visit traditional Hawaiian observation site (no notes given) Teacher gets Relates to HCPS III SC.5.8.2; SC.ES.2.4 SC.5.8.2; SC.ES.2.4 SC.ES.7, 8.4, 8.8, 8.10; SC.4.7.1, 8.7.1; SC.PS.7.2, 7.3, 7.4 SC.6.6.8, 8.8.8; SC.ES.6, 8.4 SC.ES.7, 8.4, 8.8, 8.10; SC.4.7.1, 8.7.1; SC.PS.7.2, 7.3, 7.4 B. p Students get The Solar System Pre-Test/Knowledge Survey: Kilo Hōkū (Astronomy & Navigation) Online reading: Hawaiian Planet Names at (no notes given) Teacher s Notes: for materials in Part B below including lecture notes, materials needed & student activities tips (6 pgs) Ka Hana Imi Na auao A Science Careers Curriculum Resource Project Available at: Teacher gets Relates to HCPS III SC.5.8.1, , 5.8.3, 8.8.8, SC.5.8.1, , 5.8.3, 8.8.8, SC.5.8.1, , 5.8.3, 8.8.8,

5 Optional Surveys (2): Learning Styles VARK & Multiple Intelligence (in doc above) Powerpoint & Handout: The Ordered Solar System Preview (see Ppt. on CD) with 4 pg handout, key words list & answer key Visuals Activities: (1) place 8 planets in correct order using lithographs (see teacher s notes above) & (2) view Scale in the Universe images (on CD) then Assign Object to Planet (1 pg. student handout with teacher s notes in document above) Powerpoint & Handout: Formation of the Solar System preview (see CD for Ppt) with 2 pg. handout & answer key C. p Students get Graphing Activity: Plot Distance of Planetary Objects (answers in teacher s notes above) Optional Extension Activity: Order it Up online game to order planets according to mass or density, etc. (see teacher s notes above no handout given) Post-Test/Knowledge Survey: Kilo Hōkū (Astronomy & Navigation) Comparing Planets Activity & Graphing: How Much Would a Can of Soda Weigh on Pluto? (see 5 pgs of Teacher s Notes no handout given) Worksheet: Calculating Weights on other planetary objects 2 pg. student handout (see X. Students get Teacher s Notes above for answer key) Lab: Impact Craters w/ lab directions (10 pg handout), data chart & questions handouts (3 pgs. each) plus teacher s notes (5 pgs) Appendix (see compact disk) Mauna Kea Videos: temple.html & learn.com/teamtarget/passports/mauna%20 Kea/index.htm Ka Hana Imi Na auao A Science Careers Curriculum Resource Project Available at: SC.5.8.1, , 5.8.3, 8.8.8, SC.5.8.1, , 5.8.3, 8.8.8, SC.5.8.1, , 5.8.3, 8.8.8, , SC.5.8.1, , 5.8.3, 8.8.8, SC.5.8.1, , 5.8.3, 8.8.8, SC.5.8.1, , 5.8.3, 8.8.8, SC.5.8.1, , 5.8.3, 8.8.8, Teacher gets Relates to HCPS III SC.ES.7, 8.4, 8.8; SC.4.7.1, 8.7.1; SC.PS.7.2, 7.3, 7.4 Teacher gets SC.ES.8.8; SC.PS.7.4 SC.PH.4.1; SC.ES.7 & 8; SC.PS.7.3 SC.8.7.1, Relates to HCPS III SC

6 Project: Making Astronomical Inferences SC.5.8.2; SC.ES.2.4 Video, Reading & Discussion Questions: SC Telescope Girl Units: Mars & Earth Landforms; Mars Glaciers SC.5.8.1, , 5.8.3, 8.8.8, Visuals: Hubble s Top Ten Photos SC Activity: Alka Seltzer Rockets Teachers Resources: GIS in Hawai i; Traditional Ecological Knowledge background reading; Origins of Astronomy in Hawai i (original reading) SC.ES.7, 8.4, 8.8; SC.4.7.1, 8.7.1; SC.PS.7.2, 7.3, 7.4 SC.5.8.1, , 5.8.3, 8.8.8, Y. Students get Suggested Field Trip & Guest Speakers All Islands: traditional heiau/ Hawaiian observation site O ahu: Bishop Museum Science on a Sphere, Planetarium Show; Big Island: Keck Observatory, Imiloa Astronomy Center in Hilo Guest Speakers: college & university staff & students of astronomy; cultural experts knowledgeable about navigation & astronomy Teacher gets Relates to HCPS III SC.5.8.1, 5.8.2, , 5.8.3, 8.8.8, SC.5.8.1, 5.8.2, , 5.8.3, 8.8.8, Z. Students get Careers & College Resources Career Cards for Unit 7 Kilo Hōkū (Astronomy & Navigation) careers Teacher gets Relates to HCPS III CTE This unit addresses the following: Standards/HCPS III addressed or related to this item: SC.ES.2. Standard 2: The Scientific Process: NATURE OF SCIENCE: Understand that science, technology, and society are interrelated: SC.ES.2.4 Describe technologies used to collect information about the universe; SC.PH.4. Standard 4: FORCE AND MOTION Understand the relationship between force, mass, and motion of objects; SC.PH.4.1 Solve problems using the universal law of gravity; Ka Hana Imi Na auao A Science Careers Curriculum Resource Project Available at: 3

7 499 SC/ES/PS.6 Standard 6: Physical, Earth, and Space Sciences: NATURE OF MATTER AND ENERGY: Understand the nature of matter and energy, forms of energy (including waves) and energy transformations, and their significance in understanding the structure of the universe; SC.PS.6.12 Describe nuclear reactions and how they produce energy; SC/ES/PS.7 Standard 7: Physical, Earth, and Space Sciences: FORCE AND MOTION: Understand the relationship between force, mass, and motion of objects; and know the major natural forces; gravitational, electric, and magnetic; SC.PS.7.2 Use vectors to explain force and motion; SC.PS.7.3 Explain the relationship among the gravitational force, the mass of the objects, and the distance between objects; SC.PS.7.4 Explain the magnetic and electric forces in the universe; SC.ES.8 Standard 8: Physical, Earth, and Space Sciences: EARTH AND SPACE SCIENCE: Understand the Earth and its processes, the solar system, and the universe and its contents; SC.ES.8.4 Describe how heat and energy transfer into and out of the atmosphere and their involvement in global climate; SC.ES.8.8 Describe the major internal and external sources of energy on Earth; SC.ES.8.10 Compare different theories concerning the formation of the universe; SC Explain that every object has mass and therefore exerts a gravitational force on other objects: SC Describe the composition of objects in the galaxy; SC Compare the characteristics and movement patterns of the planets in our solar system; SC Describe the major components of the universe; SC Describe the role of gravitational force in the motions of planetary systems; SC Recognize changes that indicate that a chemical reaction has taken place; SC Describe the relationship (size and distance) of Earth to other components in the solar system; SC Describe examples of what astronomers have discovered using telescopes; SC Explain that the planets orbit the sun and that the moon orbits the Earth; SC Describe that the mass of the Earth exerts a gravitational force on all objects Source: See Introduction section or go to: Career/Technical Education Standards/HCPS III related to this item: CTE Standard 2: CAREER PLANNING: Explore and understand educational and career options in order to develop and implement personal, educational, and career goals; CTE Analyze annual individual education and career goals; CTE Evaluate potential career choices in relation to personal interests, strengths, and values; CTE Apply appropriate and safe behaviors and practices in the school, community, and workplace; CTE Assess career portfolio that documents evidence of progress toward the attainment of personal, educational, and career goals; CTE Analyze the demographic, geographic, and technological trends that affect work opportunities; CTE Gather and prepare documents related to job-seeking; CTE Prepare for the job interview process; CTE Assess the compensation, lifestyle, and other benefits associated with careers of interest Ka Aha ~ a symbol for Sustainability in Hawai i ~ Past, Present &Future Ka Hana Imi Na auao A Science Careers Curriculum Resource Project Available at: 4

8 500 Activity: Making Inferences From what we can see, the universe doesn't add up. Estimates based on the amount of matter detected from Earth suggest that our universe should be rapidly expanding. But studies of the spectral fingerprints of stars don't show this expansion. That's why scientists believe there is a good deal of matter we can't see. Even though this dark matter is undetectable, its gravitational force produces the universe expansion pattern we detect. This activity page will offer: An exploration in "black box" inquiry An arena for critical observation and analysis A chance to engage inference skills Making Guesses Much of what we theorize about the universe is based on inferences. Scientists make these inferences based on hard data collected from Earth-bound instruments. In this activity, you'll get to act like a scientist and make guesses. Materials Cardboard pizza box Magnets Graph paper Tape Steel ball bearing Procedure 1. Work in teams of two. Take a cardboard pizza box and an assortment of magnets. 2. Use scissors to carefully remove the lid of the box. 3. Cover the inside bottom with graph paper. Develop a coordinate numbering system that will allow you to identify any location on the grid. 4. Turn the box over. Use tape to secure a variety of magnets to the underside of the box. 5. Turn the box right-side up. Exchange boxes with another team. 6. Place a steel bearing in the box. 7. Determine the location of the magnets by observing the behavior Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: NOT FULLY FIELD TESTED. 1

9 501 of the rolling ball. 8. Record the most likely location using the coordinate system labeled on the graph paper. 9. When you have identified the positions of the magnets, turn the box over. How close were to you identifying each position? Questions 1. What sorts of clues did you use to uncover the placement of the hidden magnets? 2. How did the magnets affect the movement of the steel bearing? 3. Would a larger box make the task easier or more difficult? Explain. Bonus Activity: Shaping Up Create a basic geometric shape out of scrap cardboard. Secure the shape in the center of a pizza box with tape. Place a marble or small ball in the box. Close the box and tape the lid shut. Exchange the mystery box with another student. Without opening the box, try to figure out the identity of the hidden geometric shape. Bonus Activity: Shakin' It Up Obtain several small plastic canisters (not transparent!). Add a spoonful of a material such as dried beans, rice, gravel or salt to each container. Mark the containers and seal them with tape. Exchange sets with another student. Without opening the film canisters, can you infer the contents of each? Bonus Activity: Create Your Own Inference Test See if you can hide an object in some kind of container that can not be detected simply through normal vision. To infer facts about your hidden object, what kinds of inferences must be made and which of our senses, tools and understanding of scientific disciplines (physics, chemistry, geology, etc.) must be used? Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: NOT FULLY FIELD TESTED. 2

10 502 Web Connection Cosmos in a Computer Cosmos/CosmosCompHome.html This site, known as "cosmos in a computer," offers background on the universe, including animated clips of its evolution. Dark Matter darkmatter/dm.html This site presents a basic overview of dark matter. HubbleSite-Universe This site discusses the Hubble space telescope and its role in cosmology. Activity 1: Grades 9-12 Making Inferences Questions & Answers 1. What sorts of clues did you use to uncover the placement of the hidden magnets? (Sounds made by rolling steel bearing, the feeling of the marble as it moved in box.) 2. How did the magnets affect the movement of the steel bearing? (The magnets exerted a force that redirected the path of the steel bearing. If the magnet was strong enough, it stopped the bearing's motion completely.) 3. Would a larger box make the task easier or more difficult? Explain. (More difficult. Since there would be a greater area for the bearing to move within, there would be less frequent interaction with the magnetic fields.) Academic Advisors for this Guide: Suzanne Panico, Science Teacher Mentor, Cambridge Public Schools, Cambridge, MA Anne E. Jones, Science Department, Wayland Middle School, Wayland, MA Gary Pinkall, Middle School Science Teacher, Great Bend Public Schools, Great Bend, KS Cam Bennet Physics/Math Instructor Dauphin Regional Comprehensive Secondary School Dauphin, MB Canada Retrieved & adapted 11/19/08 from: PBS Scientific American Frontiers. The Dark Side of the Universe. Teaching Guide. Making Inferences - High School. Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: NOT FULLY FIELD TESTED. 3

11 503 Teacher s Notes for: Group Reading Activity on Wayfinding, or Non-Instrument Navigation A) Begin as a group read the first 2 pages aloud as a whole class, or in small groups. Ask students to share information or stories related to these kinds of observations. Note: The first 2 pages of the reading are printed in the curriculum; the additional 20 pages are in the Unit 7 Appendix on the CD. B) In small groups detailed readings after the Introduction include: 1. The Sun 2. The Stars 3. The Moon 4. The Planets 5. The Ocean Swells 6. The Winds 7. Landmarks 8. Seamarks 9. Signs of Landfall 10. Land-based Seabirds 11. Traditional Tahitian Navigation 12. How the Wayfinder Locates Land Divide these among the class for 2-4 students to read. C) End by having students share their information in jigsaw groupings, or each group can simply tell the class about the information in their reading(s). Recommendation: Invite a guest speaker (navigator or Hawaiian cultural expert) to participate in this activity. Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: NOT FULLY FIELD TESTED. Retrieved 4/25/08 & adapted from: 1

12 504 Wayfinding, or Non-Instrument Navigation By Dennis Kawaharada Retrieved 4/25/08 from: Introduction (Swells Help a Navigator Hold a Course in the Daytime) Before the invention of the compass, sextant and clocks, or more recently, the satellitedependant Global Positioning System (GPS), Polynesians navigated open ocean voyages without instruments, through careful observation of natural signs. (See "Hawaiians as Seaman and Navigators" at: Navigator Nainoa Thompson of the Polynesian Voyaging Society, who was taught by Mau Piailug, a master navigator from Satawal in Micronesia, explains how a star compass is used to tell direction without instruments: "The star compass is the basic mental construct for navigation. We have Hawaiian names for the houses of the stars-the places where they come out of the ocean and go back into he ocean. If you can identify the stars, and if you have memorized where they come up and go down, you can find your direction. The star compass is also used to read the flight path of birds and the direction of waves. It does everything. It is a mental construct to help you memorize what you need to know to navigate. "How do we tell direction? We use the best clues that we have. We use the sun when it is low on the horizon. Mau has names for how wide and for the different colors of the sun path on the water. When the sun is low, the path is tight; when the sun is high it gets Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: NOT FULLY FIELD TESTED. Retrieved 4/25/08 & adapted from: 2

13 505 wider and wider. When the sun gets too high you cannot tell where it has risen. You have to use other clues. "Sunrise is the most important part of the day. At sunrise you start to look at the shape of the ocean-the character of the sea. You memorize where the wind is coming from. The wind generates the swells. You determine the direction of the swells, and when the sun gets too high, you steer by them. And then at sunset we repeat the observations. The sun goes down-you look at the shape of the waves. Did the wind change? Did the swell pattern change? At night we use the stars. We use about 220 stars by name-having memorized where they come up, where they go down. "When I came back from my first voyage as a student navigator from Tahiti to Hawaii the night before he went home, Mau took me into his bedroom and said "I am very proud of my student. You have done well for yourself and your people." He was very happy that he was going home. He said, "Everything you need to see is in the ocean but it will take you twenty more years to see it." That was after I had just sailed 7000 miles. "When it gets cloudy and you can't use the sun or the stars all you can do is rely on the ocean waves. That's why he said to me, "If you can read the ocean, you will never be lost." One of the problems is that when the sky gets black at night under heavy clouds you cannot see the swells. You cannot even see the bow of the canoe. And that is where people like Mau are so skilled. He can be inside the hull of the canoe and just feel the different swell patterns moving under the canoe and he can tell the canoe's direction lying down inside the hull of the canoe. I can't do that. I think that's what he learned when he was a child with his grandfather. "The Southern Cross is really important to us. It looks like a kite. These two stars in the Southern Cross always point south (Gacrux on top and Acrux on the bottom). If you are traveling in a canoe and going south, these southern stars are going to appear to be traveling the higher and higher in the sky each night. If you went down to the South Pole, these stars are going to be way overhead. If you are going north to Hawai'i, the Southern Cross travels across the sky in a lower and lower arc each night. When you are at the latitude of Hawai'i, the distance from the top star (Gacrux) to the bottom star (Acrux) is the same distance from that bottom star to the horizon. That only occurs in the latitude of Hawai'i.lf you are in Nuku Hiva at 9 S, the distance between the bottom star in the Southern Cross and the horizon is about nine times the distance between the two stars." The following techniques are used by Hawaiian and Polynesian navigators taught by Mau and Nainoa. The art, as it is practiced today in Hawai'i, uses a Hawaiian star compass developed by Nainoa, incorporating principles from Mau's Micronesian star compass and traditional Hawaiian names for directions and winds. Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: NOT FULLY FIELD TESTED. Retrieved 4/25/08 & adapted from: 3

14 506 Teacher s Notes: Looking for Life in the Solar System Mini-Lab Typically, living organisms are viewed as forms of life that use respiration and are often not thought of as organisms that do not require oxygen to thrive. However, many living organisms use another chemical process known as fermentation to produce energy. Even though these organisms do not use respiration, they are considered living because they fulfill many aspects of the fundamental criteria for life. These organisms react to stimuli, grow, have a form of locomotion, use some type of cellular division or reproduction to replicate themselves and show signs of metabolic reactions. In this lab, students will develop ideas as to what dictates whether an organism is living or not. They will incorporate the fundamental criteria for life in their ideas and make observations utilizing this information. As students observe live yeast cultures reacting with sugar (sucrose) and water, they will also be observing chemical reactions between Alka-Seltzer, sugar (sucrose) and water. They will compare their findings and infer if it is possible for life to thrive beyond our planet. Objective To use visual observations to view reactions between sugar-water and both living organisms (yeast) and non-living substances. Students will verify if a living organism or a non-living substance causes the reaction they view. They will use the information they obtain to infer if life is possible beyond our planet. Learning Outcomes Enable students to: Form an operational definition of life State relationships between the water samples using their operational definition of life Learn to take observational data Make inferences about the possibility of life in our/other solar system(s) Duration of Lesson 1-2 hours Preparation Teachers should precut pieces of wax paper to be used when measuring the sugar on the scale. See student handout for materials needed. Procedure Give students the handout below. Discuss what characteristics make something alive or not. For example: a bear and a chair both have legs, but one cannot move on its; therefore, independent movement might be one characteristic that indicates life. Not every living organism needs legs or roots, but all need a mode of locomotion or a way to get nutrients. Ask what other criteria does a bear have to indicate it is alive compared to a chair (i.e. it breathes). Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to:

15 507 Mini-Lab: Looking for Life in the Solar System Keywords to Know Anaerobic occurring in the absence of oxygen or not requiring oxygen to live Aerobic living or occurring in the presence of oxygen Respiration the end result of the physical and chemical processes an organism uses to convey oxygen to tissues and cells; oxidation products, CO2 and H2O are given off as a by-product. Fermentation the process of deriving energy from the oxidation of organic compounds, such as carbohydrates; anaerobic reaction used to produce energy; can be used in the presence of oxygen, but does not utilize the oxygen Organism a form of life composed of mutually interdependent parts that maintain various vital processes. Replication The process by which genetic material, a single-celled organism or a virus reproduces or copies itself; cellular replication Metabolism chemical processes by which cells produce the substances and energy needed to sustain Materials Needed Dictionaries and Encyclopedias Examples of living organisms (both aerobic and anaerobic) and non-living objects Table sugar (sucrose) Active Dry Yeast packets Alka-Seltzer tablets Warm water (3) 500mL beakers Paper and writing utensils to write/draw observations Scale able to measure in grams Small pieces of wax paper to measure sugar on Procedure: work in groups to determine the fundamental criteria for life Use dictionaries and encyclopedias to research what criteria is necessary for life forms to thrive. Write your criteria in a table on a separate paper with your group s names on it. Show you understand what aerobic and anaerobic life forms are, and incorporate these terms in your fundamental criteria for life. Each group will gather: (3) 500mL beakers; (1) packet of Active Dry Yeast; (1) Alka-Seltzer tablet; water; (15g) of sugar (sucrose); (1) piece of wax paper; and paper/writing utensils. Mix yeast and sugar, place on wax paper, and add a small amount of warm water. Observe and record the reaction. Wait 15 minutes and observe again. Wait another 15 minutes and observe again. Crush Alka-Seltzer and mix with sugar, place on wax paper, and add a small amount of warm water. Observe and record the reaction several times as above. Try other mixes of these substances, if time. Which mixtures meet your criteria for life and which don t? Why? Do you think you should revise your criteria? Write a paragraph explaining your answers. Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to:

16 508 Space Rocks Could Reseed Life on Earth By Aaron Gronstal Astrobiology Magazine 5 May Asteroid and comet impacts on Earth can cause catastrophic extinction events. They can also bring life back, new research shows. Many scientists believe that a massive rock from space came crashing down 65 million years ago at the end of the Cretaceous Period. The resulting blast set forests ablaze. The skies of Earth were filled with ash that blocked out the sun, and the planet went cold. Vegetation died in the absence of sunlight. Shortly thereafter, the dinosaurs and many other life forms on Earth went extinct. Millions of years of evolution were wiped clean in an instant. It's frightening that one instantaneous event could completely change the face of life on Earth. However, a new study supports longstanding suggestions that asteroid impacts could also help spread life throughout the universe. Rocks that are ejected from the Earth or any other life-bearing planet by an asteroid impact might actually protect microbes living inside them while they float through space. These rocks could then fall to the surface of other planets, or even back to their planet of origin. In this way, the microbes could return to their home planet and "re-colonize" the surface after the disastrous effects of the asteroid impact have worn off. Blast off In order for organisms to survive a trip into orbit, they must endure a series of lifethreatening events. First there's the asteroid impact itself. Then there's the force of being launched into space. Next, they must travel in the harsh environment of space until a planet's gravity reels them in. This means facing an environment of extreme cold, intense radiation and vacuum exposure. Finally, they need to fall down through the atmosphere, experiencing extreme pressure, heating and the shock of landing. Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 1

17 509 Previous studies have shown that some rock-inhabiting organisms, known as "endoliths," might be able to survive a trip through space and a plunge through a planet's atmosphere to the surface. However, nobody knew whether these organisms could survive the initial trip into space. Recently, an international team of researchers, led by Gerda Horneck of the Institute of Aerospace Medicine in Köln, Germany, selected a number of hardy microbes from Earth and tested their ability to hitchhike aboard rocks similar to Martian meteorites. The organisms used in the study included bacterial endospores, endolithic cyanobacteria and lichens. This selection provided a wider range of organisms than in other studies performed to date, including not just simple bacteria but also more complex eukaryotic organisms. Smashing life Chroococcidiopsis, which was used in this study, is shown here living in a rock from the Negev Desert in Israel. The green line running across the top of the rock is a thin endolithic film formed by the organism. These microbes live just below the surface of the rock, protected from the Sun's UV radiation. Credit: Gerda Horneck The researchers looked at previous studies of Martian meteorites that provided information about the kinds of forces needed to eject rocks from a large planet. Using this data, the researchers developed a series of tests designed to simulate these pressures on the selected organisms. By smashing the life-containing rocks between metal plates, the researchers were able to determine which organisms are capable of surviving different pressures caused by asteroid impacts and ejection into space. Ultimately, they discovered that a wide range of organisms would be capable of surviving impacts on Mars or Earth. "Our results enlarge the number of potential organisms that might be able to reseed a planetary surface after early very large impact events, and suggest that such a reseeding scenario on a planetary surface is possible with diverse organisms," the researchers report. The research is detailed in the Spring 2008 issue of the journal Astrobiology. Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 2

18 NAME: 510 CLASS: Unit 7 Pre-/Post-Test Kilo Hōkū (Astronomy & Navigation) Part A: The Planets Knowledge Survey Questions 1) List the three types of objects that orbit our Sun. 1) 2) 3) 2) List all eight planets, in order starting from the planet closest to the Sun and moving out to the planet farthest from the Sun. 1) 2) 3) 4) 5) 6) 7) 8) 3) What are the two types of planets in our Solar System? 1) 2) 4) In the space below compare and contrast the four major properties of the two types of planets in our Solar System (e.g., what differences distinguish them as one type or the other). Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 1

19 NAME: 511 CLASS: 5) Which of the following is part of the International Astrophysical Union s 2006 definition of a planet? (Carefully circle the letters of all that apply). A) The object must orbit the Sun. B) The object must be bigger than the Moon. C) The object is large enough for its own gravity to make it round. D) The object has "cleared its neighborhood" of smaller objects. E) The object must lie within the ecliptic plain. 6) Why is Pluto no longer considered a planet? 7) In the solar nebula, where were elements that comprise rocky materials more likely to condense? (Carefully circle the letter of the correct answer). A) close to the Sun B) far away from the sun C) both close and far away from the Sun D) neither close nor far away from the Sun 8) True or False: (Carefully circle the correct answer). 1. All 8 planets in our Solar System are spaced equally apart. True or False 2. Earth is the biggest terrestrial planet. True or False 3. You would weigh 10 times more on Saturn than you would on Earth. True or False 4. The Sun is bigger than all the other planets combined. True or False 5. The Big Bang formed the Solar System. True or False Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 2

20 514 UNIT 7: Kilo Hōkū - Astronomy & Navigation Teacher s Notes for: The Ordered Solar System Before the students can begin their Tour Through the Solar System they need to have a roadmap. This exercise provides both an internal roadmap, by teaching the students about their learning style, and an external map when they create a model Solar System. The model Solar System can be left up in the classroom for the whole unit so that students can review their progress in each lesson. This section consists of 6 activities. The first 3 activities are core to the learning outcomes and the last 3 are additional that can be done if there is time. Objectives The goal of this unit (Part B of Unit 7) is to teach the order and general properties of the planetary objects in our Solar System. Learning Outcomes To enable students to: Learn there are now 8 planets in the Solar System and why Arrange the objects in our Solar System in the correct order Learn that planets are not equally spaced Learn Gas Giants are bigger and farther apart than terrestrial planets Understand planets are not all alike (e.g., not all the same size), some have atmospheres, some don t, some have moons while others do not Gravity varies on each planet as a function of mass and planet radius Sun is ~ 100 x bigger than Earth Jupiter is ~ 10x bigger than Earth Although Mars is 50% bigger in size relative to Mercury, they have equivalent gravity Explain why the Earth has a gravitational force similar to Saturn, even though Saturn is 8x s bigger and 100x more massive (it is less dense) 1. Optional Surveys: VARK and Multiple Intelligence Have students take the VARK or multiple intelligence surveys at: Multiple Intelligence Survey ons/questions.cfm Visual, Aural Read/Write, and Kinesthetic (VARK) Survey (website addresses listed below). Have the students record their results for the different learning styles. The purpose of taking the surveys: to support those who have learning challenges Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 1

21 515 to provide teachers a demographic of how students learn so that they can develop additional learning strategies to target the different learning styles of students to form students for group work so that each learning style is represented In this curriculum we have attempted to stimulate the four different learning styles: Visual, Aural, Reading/Writing and Kinesthetic. 2. Introductory Lecture The Ordered Solar System Show the NASA Powerpoint The Ordered Universe (see preview in Part A of this unit and slideshow on compact disk included in this curriculum), which covers the definitions of a planet, gas giants versus terrestrial planets, and introduces the terms dwarf planet and plutoid. These keywords, plus Kuiper Belt and Asteriod Belt are defined at the end of the accompanying Powerpoint handout. Source: Discussion topics: 1) Why does the Solar System contain only eight planets and why is Pluto no longer a planet? o Recent discoveries of large objects orbiting the Sun beyond Neptune and Pluto have raised the question, What is a planet? The International Astronomical Union (IAU) has re-examined the way planetary bodies are classified, and in August 2006 it passed a resolution redefining the criteria for planetary status. 2) What three properties define a planet? A planet is defined by three properties: It is a celestial body that orbits the Sun It is massive enough that its own gravity causes it to form in a spherical shape There are no other objects of comparable size other than its own satellites (e.g., moons) in its orbit 3) What do objects in Pluto s orbit have to do with its new classification? An object is considered to have cleared the neighborhood around its orbit when there are no other objects of comparable size within its orbit, except for its own moons. For instance, Pluto shares its orbit with Kuiper Belt objects; thus it has not cleared its orbit and does not meet the requirements for the new definition of a planet. Using this definition, the IAU has determined that our Solar System now has eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 2

22 516 4) What is Pluto now known as? Pluto has been reclassified as a dwarf planet, and because it is located beyond the orbit of Neptune, it s also known as a plutoid. Another dwarf planet that is also a plutoid is Eris which is an icy body that is about the same size as Pluto but is farther away from Earth (the distance from Pluto to Eris is almost the same distance as the distance from the Sun to Pluto). It was partly due to the discovery of Eris that the IAU re-defined planets. 5) Is Ceres the same as Eris? Ceres is also a dwarf planet, but it is not a plutoid because it is not located beyond the orbit of Neptune. Ceres is the largest asteroid found in the Asteroid Belt, which is located between the orbits of Mars and Jupiter. Additional background reading can be found in the Unit 7 Appendix on the compact disk included with this curriculum see Solar System Lithographs: Visuals & Notes file. 3. Planet Activities (Order & Size) Review: Place Planets in Correct order Have students review the 8 planets and their order from the Sun. Only a preview of the images are printed in the curriculum. A full set of Lithographs are in the Unit 7 Appendix in three versions: Our Solar System Lithographs (Visuals & Notes) Original Our Solar System Lithographs (visuals only) Our Solar System Lithographs (Visuals & Notes) half page version Students can recite this mnemonic or make there own to memorize the planets order: My Very Excellent Mother Just Served Us Noodles Bonus Questions: See Unit 7 Appendix on compact disk for 1 page handout for students. They will need to view the full set of lithographs and notes (online at: System-Lithograph-complete-Set.pdf. No answer key is provided. Scale of the Planets Activity: Assign Object to Planet View the Scale in the Universe images (3 page handout printed in curriculum or show the 5 color slides see pdf document in Unit 7 on CD). Then give groups various objects (see table below) and ask them to place them on the Scale in the Universe Activity handout under the correct planet names. Discuss answers and share facts in table below with class. Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 3

23 517 Example of objects to use to represent relative Planet and Plutoid sizes Object Diameter (miles) Scale Object Scale Object Scale Distance from Sun (inches) Sun 864, inch sphere grapefruit n/a Mercury 3,100 brass BB salt grain 3-1/8 Venus 7,550 marble raw sugar 6-3/4 Earth 7,927 marble raw sugar 9-1/4 Mars 4,200 1/4" bead salt 14-1/8 Jupiter 88,900 softball cherry 48-1/2 tomato Saturn 75,200 baseball green 89-1/4 grape Uranus 29,200 golf ball frozen pea 177-3/4 Neptune 28,000 ping pong ball frozen pea 279-3/4 Pluto 1,500 grain of sand speck of baking soda Plot the Distance of the Planetary Objects Using the data table provided in the handout, have the students plot the distance of the planets in A.U. (Astronomical Unit) from the Sun. (1 A.U. = 149,598,000 km, the distance from the Earth to the Sun.) The goal is to be able to emphasize the distance between planetary objects, a common misconception is that the planets are equally spaced. It is good to have the students graph the distance between the planets by hand rather than in Excel so that they have to think about the scale that they are going to use and to see how great the distance is. The more advanced students can calculate the distances between planets, in A.U., themselves. Download graph paper from: Select the grid size that works best for this activity, for example: Minimum border = 0.5 cm Grid line width = 0.5 points Grid spacing = 2 lines/cm Online Activity: Another way for the students to visual the distance between the planets can be seen at: It is a tour of the Solar System with relative distance between each planet illustrated by scrolling between planets. Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 4

24 Extension Option: Order it Up Game ( Alternatively, if the classroom has a computer with Internet access and a computer projector then the game, Order it Up can be projected onto the screen. "Order It Up" is a computer game about solar system statistics in which the players put planets in order on the basis of various statistics (i.e. mass, # of moons, etc.). Players must complete several puzzles to finish the game and scores are kept with a jumbled photo of a planet that un-jumbles as the player correctly places planets in order. The game gives the players 10 hints. It takes between 5 and 10 minutes for individuals to play. The individual puzzles (8-10 of them in random order) make good think-pair-share activities. For each list, give the student pairs 2 minutes to assemble a list. Then the class as a whole should direct the instructor to enter the answers into the applet and decide whether to go for a hint. Suggestions for use: Use this web page as a study guide In class as a game that 2 people or 2 groups of students can compete against each other. Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 6

25 520 Note to Teachers: The next document gives a preview of the Powerpoint slide show found on the compact disk in this curriculum (see each Unit Appendix). The actual Powerpoint slides may also include presenter s notes that are not printed in the curriculum pages, but will appear when you view the slides (select normal under viewing options).

26 521 Warm Up Questions The Ordered Solar System Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 1. Which planet is bigger, Mercury or Jupiter? 2. Are the gas giant planets closer to the Sun than the rocky planets (yes/no)? 3. How many planets are in the Solar System? 4. Is the Sun bigger, smaller, or the same size as the Moon? 5. What is the difference between the Solar System and the Milky Way Galaxy (just one sentence)? 1 2 Why are there only 8 planets now? What is a planet? Three types of objects orbit our Sun: 1. Planets 2. Dwarf Planets Plutoids 3. Small solar system bodies 3 In August of 2007 the International Astronomical Union redefined what a planet is (no official scientific definition of a "planet" existed before). A planet: 1. Is a body that orbits the sun (this definition only applies to our Solar System) 2. Is large enough for its own gravity to make it round 3. And has "cleared its neighborhood" of smaller objects So a new the category of dwarf planet was created, which currently includes Pluto, Eris*, and Ceres**. *Eris is the largest known dwarf planet in the Solar System and the ninth largest body known to orbit the Sun. Its distance from the Sun is 97 AU. **Ceres is the smallest identified dwarf planet in the Solar System and, 4 because it s the largest asteroid, the only dwarf planet in the asteroid belt. What is a Dwarf Planet? Only 5 Dwarf Planets recognized so far but there may be as many as 200 Celestial body orbiting the Sun Massive enough to be rounded by its own gravity BUT has NOT cleared its neighboring region of planetesimals Is not a satellite A plutoid is a dwarf planet beyond the orbit of Neptune 5 Pluto, approximate true color Ceres, seen through (Hubble telescope) Haumea,, with its 2 moons, Hi iaka iaka and Namaka (Artist s s conception) Makemake, (Artist s s conception) Eris,, seen through (Hubble telescope) 6

27 522 Pacific Island Names for Planetary Objects Pacific Island Names for Planetary Objects Haumea is the Hawaiian goddess of childbirth and fertility. The the moons "Hi iaka" and "Namaka are named after after two of Haumea's daughters. Makemake is the creator of humanity in the mythos of the Rapanui, the native people of Easter Island. The name choice preserves the planetary object's connection with Easter What are Small Solar System Bodies? Terrestrial vs.. Gaseous Planets Terrestrial Gaseous Neither a planet nor a dwarf planet All other objects orbiting the Sun All minor planets except dwarf planets Asteroids (except Ceres, the largest) Comets Not massive enough to be rounded by its own gravity Mercury, Venus, Earth, Mars 1. Rocky More dense 2. Smaller 3. More closely spaced 4. Closer to the Sun Jupiter, Saturn, Uranus, Neptune 1. Gaseous, has more He and H Less dense (Saturn would float) 2. Larger 3. Spaced farther apart 4. Farther from the Sun 9 10 Terrestrial Planets Jovian Planets, or Gas Giants Uranus Neptune Jupiter Saturn Mars Venus Mercury From Nick Strobel s Astronomy Notes at 11 From Nick Strobel s Astronomy Notes at 12

28 523 Do you see patterns or anomalies in these data? On which planet would you weigh the most? ,000 light years across 1,000 light years thick 200 billion stars The Milky Way Galaxy You are here 15

29 NAME: 524 CLASS: UNIT 7: Kilo Hoku - Astronomy & Navigation The Ordered Solar System Powerpoint Questions & Key Words DIRECTIONS: Complete the notes below as you watch the Powerpoint slideshow Slide 3: Three types of objects orbiting our Sun Slide 4: What defines a planetary object as a planet? Why is Pluto no longer considered a planet? Slide 5: What defines a planetary object as a Dwarf Planet? What is the difference between a Dwarf Planet and a plutoid? Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 1

30 NAME: 525 CLASS: Slide 6: List the 5 recognized Dwarf Planets Slide 7: Who was the Dwarf Planet Haumea named after? Who were Haumea s two moons Hi iaka and Namaka named after? Slide 8: Who was the Dwarf Planet Makemake named after? Slide 9: Three objects that do not fall under the classification of a Dwarf Planet or planet (Small Solar System Bodies) If an object is not massive enough to be rounded by its own gravity, it falls under what category? *Dwarf Planets *Planets *small Solar System bodies Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 2

31 NAME: 526 CLASS: Slides 10-12: Terrestrial planets are List the 4 planets in our Solar System that are considered terrestrial Gaseous planets are List the 4 planets in our Solar System that are considered gaseous Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 3

32 NAME: 527 CLASS: Slide 13: Which planet in our Solar System has the hottest temperatures? Which planet in our Solar System has the coolest temperatures? One day on Venus is equal to haw many days on Earth? Which 4 planets have a one-day period that is equal to less than one Earth day? Slide 14: Which planet has the largest mass? Which is the least dense planet? Which is the most? Which 3 planets have a stronger gravity field than Earth? Slide 15: How many stars are estimated to be in the Milky Way Galaxy? How thick is the Milky Way Galaxy? How many light years across is the Milky Way Galaxy? Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 4

33 NAME: 528 CLASS: The Ordered Solar System: Key Words Celestial- of or relating to the sky or visible heavens <the sun, moon, and stars are celestial bodies. Satellite- A natural satellite or moon is a celestial body that orbits a planet or smaller body. Technically, the term natural satellite could refer to a planet orbiting a star, or a dwarf galaxy orbiting a major galaxy, but it is normally synonymous with moon. Planet- A planet is a body that orbits the Sun (e.g., this definition only applies to our Solar System), is large enough for its own gravity to make it round, and has "cleared its neighborhood" of smaller objects. Gas Giants- Jupiter, Saturn, Uranus, and Neptune are all examples of gaseous planets. They have more He and H, are less dense, are all ~ larger than Earth, are spaced farther apart than terrestrial planets, and are located farther from the Sun than terrestrial planets. Terrestrial planet- Mercury, Venus, Earth, Mars are terrestrial planets. They are also known as rocky planets. They are more dense, more closely spaced, and are smaller than the gaseous planets. They are also closer to the Sun than the gaseous planets. Plutoid- A plutoid is a dwarf planet located beyond the orbit of Neptune Dwarf planet- fails at least one of the IAU criteria for being a planet. IAU- The International Astronomical Union (IAU) was founded in Its mission is to promote and safeguard the science of astronomy in all its aspects through international cooperation. Kuiper Belt- The Kuiper belt is a region of the Solar System that is located beyond Neptune s orbit and extends ~30 50 AU (or 30 to 50 times the distance of the Earth from the Sun). There are hundreds of orbiting Kuiper belt objects (KBOs); the dwarf planet Pluto is one of these KBOs. Asteroid Belt- The asteroid belt is a region of the Solar System that is located between the orbits of Mars and Jupiter ( A.U.). Most asteroids are located here. There are more than 20,000 numbered asteroids in the asteroid belt and there are probably millions of asteroids in total. The range in size from Ceres, 940 km in diameter ~ one-quarter the diameter of our Moon, to bodies that are less than 1 km across. Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 5

34 533

35 National Aeronautics and Space Administration Our Star The Sun

36 535

37 536 THIS IS A HUBBLE TELESCOPE ULTRA DEEP FIELD INFRARED VIEW OF COUNTLESS "ENTIRE" GALAXIES BILLIONS OF LIGHT-YEARS AWAY. ANTARES IS THE 15TH BRIGHTEST STAR IN THE SKY. IT IS MORE THAN 1000 LIGHT YEARS AWAY. NOW HOW BIG ARE YOU? NOW TRY TO WRAP YOUR MIND AROUND THIS... BELOW IS A CLOSE UP OF ONE OF THE DARKEST REGIONS OF THE PHOTO ABOVE.

38 537 NOW HOW BIG ARE YOU? AND HOW BIG ARE THE THINGS THAT UPSET YOU TODAY? KEEP LIFE IN PERSPECTIVE. AND DON'T SWEAT THE SMALL STUFF!

39 538 Scale in the Universe Activity Put object representing each planet into the space provided in table below. Mercury Venus Earth Mars Jupiter Saturn Uranus Neptune Pluto Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to:

40 539 Note to Teachers: The next document gives a preview of the Powerpoint slide show found on the compact disk in this curriculum (see each Unit Appendix). The actual Powerpoint slides may also include presenter s notes that are not printed in the curriculum pages, but will appear when you view the slides (select normal under viewing options).

41 1 540 Formation of Our Solar System Some data to explain: 1. Planets isolated 2. Orbits ~circular / in ~same plane 3. Planets (and moons) travel along orbits in same direction. same direction as Sun rotates (CCW) Venus slowly rotates CW Uranus on its side Pluto on its side captured asteroid? Moons go CCW around planets (few exceptions) Solar System is highly differentiated Terrestrial planets Slow rotators, few or no moons Gas Giants Fast rotators, many moons Asteroids Old Different from rocky or gaseous planets Comets Old, icy Do not move on same plane as planets Image: Lunar and Planetary Laboratory: Lunar and Planetary Institute image at Planets, most moons, and asteroids revolve around the Sun in the same direction (CCW) They all move in ~ circular orbits Pluto-special case Orbit is highly inclined (18 ) oval shape Some more data to explain: 4. Most planets rotate in this same direction Mercury 0 Venus 177 Earth 23 Mars 25 And some more data to explain: 5. Solar System highly differentiated: Terrestrial Planets (rocky, dense with density ~4-5 g/cm3) Jovian Planets (light, gassy, H, He, density 0.7-2) Jupiter 3 Saturn 27 Uranus 98 Neptune NASA images edited by LPI 6 Images: Lunar and Planetary Laboratory: How Did We Get a Solar System? How Did We Get a Solar System? How Did We Get a Solar System? Gravity concentrates most stuff near center Heat and pressure increase Huge cloud of cold, thinly dispersed interstellar gas and dust (mostly H & He) Image: LPI Active region of Star formation in the Large Magellanic Cloud (LMC) satellite galaxy of Milky Way (Hubble) Concentrations of dust and gas in the cloud; material starts to collect (gravity > magnetic forces) Hubble image at Hubble image at Image: LPI Collapses central proto-sun rotates faster (probably got initial rotation from the cloud) Image: LPI

42 How Did We Get a Solar System? Rotating, flattening, contracting disk - solar nebula! How Did We Get a Solar System? How Did We Get a Solar System? Metallic elements (Mg, Si, Fe) condense into solids at high temps. Combined with Oxygen to make tiny grains Equatorial Plane Orbit Direction A7er ~10 million years, material in center of nebula hot enough to fuse Hydrogen (H)...here comes the Sun NASA/JPL-Caltech Image at 10 NASA artwork at Lower temp (H, He, CH4, H2O, N2, ice) - outer edges Planetary Compositions Hubble photo at How Did We Get a Solar System? How Did We Get a Solar System? Terrestrial planets Heavier elements stable at higher temperature Condensed in inner nebula Inner Planets: Hot Silicate minerals, metals, no light elements, ice Begin to stick together with dust clumps Outer Solar System Cold ices, gases 10x more particles than inner May have formed icy center, then captured lighter gases (Jupiter and Saturn first? Took H and He?) Leave C,O, and N for the others Image: LPI 13 Image: LPI Gas giants Lighter elements (H, He, C, O, N) stable at lower temperature Condensed in outer nebula Where do Comets Originate? Orbital paths of comets Highly elliptical (oval-shaped) 1 complete orbit is called a period Short-period comets Revolve around the Sun less than 200 yrs E.g. Comet Halley Paths are close to the same plane of orbit as planets Orbit is the same direction as the Sun Originate from the Kuiper belt Long-period comets Longer than 200 years to go around once Orbital path is random Direction and plane of orbit E.g. Comet Hale-Bopp Originated in Oort cloud Spherical cloud, 20 trillion miles beyond the Sun

43 How Did We Get a Solar System? How Did We Get a Solar System? How Did We Get a Solar System? Accretion - particles collide and stick together or break apart gravity not involved if small pieces Form planetesimals, up to a few km across Gravitational accretion: planetesimals attract stuff Large protoplanets dominate, grow rapidly, clean up area ( takes ~10 to 25 My) 19 Image: LPI 20 Image: LPI 21 Early burst of solar wind - sweeps debris out of system Gravitational accretion of gas for protoplanets in the coolest nebular parts Image: LPI Smaller protoplanets (inner solar nebula) Unable to accrete gas because of their higher temperature Obtain their atmospheres from the impact of comets Largest protoplanets (outer solar nebula) Accrete gas because of their cooler temperature Strongly influence the orbits of the remaining comets Either send them out to the Oort cloud or Send them inward where they collide with the terrestrial planets How Did We Get a Solar System? The Asteroid Belt? Should have been a planet instead of a debris belt? Jupiter kept it from forming How Did We Get a Solar System? Beyond the Gas Giants - Pluto, Charon and the Kuiper Belt objects Chunks of ice and rock material Little time / debris available to make a planet slower!! Taken from Hubble Telescope Charon is Pluto s moon, only a Little smaller than Pluto Pluto s surface temp. is as low as -400 F From the surface of Pluto, the Sun looks like a very bright star Eros image at Early in the Life of Planets Planetesimals swept up debris Accretion + Impacts = HEAT Eventually begin to melt materials Iron, silica melt at different temperatures Iron sank density layering Mercury Average density of 5430 kg/m 3 Second highest density of all planets Like Earth, has an Iron core 2/3 to ¾ of the radius of the planet! Iron-Nickel core Venus Composition ~ to Earth Crust km thick Mantle Core Iron-Nickel Average density is 5240 kg/m 3 25 Image from LPI:

44 Earth Crust, mantle, and core Crust ~ 30 km thick for land (granite) ~ 5 km for oceanic crust (basalt) Mantle Core, Iron-Nickel Liquid outer core Inner solid core Average density ~ 5520 kg/m 3 Mars ~ ½ the diameter of Earth Crust Mantle Core, Iron-Nickel and Iron sulfide Density ~ 3930 kg/m 3 Pluto Structure not very well understood Surface is covered with methane ice Surface temp ~ 400 F Frozen methane shows a bright coloration Density ~ 2060 kg/m 3 This low of a density suggests that the planet must be a mix of rock and ice Planetary Interiors Planetary Interiors Image from LPI: Differentiation Separation of homogenous interior into layers of different compositions Early hottest time dense iron-rich material core Releases additional heat Leaves mantle with molten ocean enriched in silica Crust eventually forms from lightest material Differentiation Continues! Radioactive decay = primary heat source Image from LPI: Partial melting of mantle material rising magma volcanoes / lava flows

45 NAME: 544 Solar System Formation: PowerPoint Notes Sheet CLASS: DIRECTIONS: Work with a partner or team to complete these notes Slide 2: Do planets and the Sun orbit in the same direction? What direction do they orbit? Which planet slowly rotates? Which planets rotate on their sides? Slide 3: Which planets rotate faster? Which type of planets have many moons? Slide 4: What is special about Pluto? Slide 5: List the planets in order of increasing tilt angle. Slide 6: What is the average density of the Terrestrial planets? What is the average density of the Gas giants (Jovian Planets?) Slide 7: What types of gases exist in an area of star or solar system formation? Slide 11: What is the first thing that happened when the Sun started to form? Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 1

46 NAME: Slide 12: 545 CLASS: Why are the inner planets made up of metallic elements and the outer planets gaseous? Slide 15: Why might Jupiter and Saturn be made up of Hydrogen and Helium and the other gas giants made up of additional gases? Slide 16: Where are two places that comets come from? Slide 17: How long does it take for a short-period comet to revolve around the Sun? What direction do short-period comets orbit the Sun? Where do short-period comets originate? Slide 18: How long does it take for a long-period comet to revolve around the Sun? What direction do long-period comets orbit the Sun? Where do long-period comets originate? Slide 22: Why are the smaller protoplanets unable to accrete gas? Slide 24: What is the name of Pluto s moon? What temp does the surface of Pluto reach? Slide 25: Why do some planets have metal cores? What are the crusts made out of? Slides Write down the densities of Mercury, Venus, Earth, Mars, and Pluto. Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 2

47 NAME: 548 CLASS: Plot the Distance of the Planetary Objects DIRECTIONS: On graph paper, plot the distance between the planetary objects using the data in the table below. Use the data from the column that lists the average distance from the Sun for the x-axis and use a constant y-axis value for each planetary object listed in the table s left column. Object Avg. Distance from the Sun (AU) Sun 0 Mercury 0.4 Venus 0.7 Earth 1 Moon 1 Mars 1.5 Jupiter 5.2 Saturn 9.5 Uranus 19.2 Neptune 30.1 Pluto 39 Use pencil! Orient the graph paper in the landscape direction. Do NOT use Excel or any other graphing program. Devise your own scale i.e., how many boxes on your graph paper will it take to equal 1 AU (Astronomical Unit) Label each planet on the graph In addition to labeling each planet, also record its x-axis value (how many x-axis values per AU?) Experiment with changing the scale of your graph paper so that the planets are not on top of one another nor are excessive sheets of graph paper required. Use your graph to answer the following questions: 1. How do the distances to the Sun compare for the inner (Mercury through Mars) versus the outer (Jupiter through Pluto) planetary objects? 2. Between which two planets does the Solar System double in size? Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to:

48 549 UNIT 7: Kilo Hoku - Astronomy & Navigation Teacher s Notes for Part C: Comparing Planets Mass, Density & Gravity 1. How much would a can of soda weigh on Pluto? Weigh pennies and place them in soda cans to get the approximate weight of a can on each planetary object or use a material such as quickcrete instead. (More advanced students can calculate the number of pennies needed for each can.) It is helpful to use a different type of soda can for each or paint each can a different color. This allows the students to say, for example, the Coke can represents what a can of soda would weigh on Jupiter and the Pepsi can represents what a can of soda would weigh on Neptune. Tape the tops of each soda can so that the pennies will not fall out. The amount of gravity a planet possesses depends on its mass and volume (density) and radius. Function of mass and radius: g = (GM/R 2 ) where: G = 6.67x10-11 m 3 kg -1 s -1; M =mass of object; R = radius of object A person's weight depends on the mass of the person, mass of the planet and the planet s radius. Therefore a person will weigh less on a planet that has less mass and similar radius than the Earth and weigh more on a planet that has a larger mass than the Earth and similar radius. This is illustrated by using a simple can of soda pop. On Earth a 16-ounce can weighs 386 grams. Take several other empty soda cans and fill them with material (lead pellets, marbles, rock, etc.) until they weigh the amounts for each planet shown on the table below (this lists how much a full can of soda would weigh on various planetary objects as well as other statistics about the planetary objects). Body grams Pennies Mass (kg) Radius (km) Density kg/m 3 *Gravity (GM/R 2 ) Sun 10,808 ~ E+30 69,595 1, Mercury E+23 2,440 5, Venus E+24 6,052 5, Earth E+24 6,371 5, Moon E+22 1,738 3, Mars E+23 3,390 3, Jupiter E+27 71,492 1, Saturn E+26 60, Uranus E+25 24,973 1, Neptune E+26 24,764 1, Pluto E+22 1,151 2, **Relative Gravity * g = (GM/R 2 ) where G = 6.67x10-11 m 3 kg -1 s -1; M =mass of object; R = radius of object ** Object of interest/earth s Gravity, e.g., for the Sun /9.82 = 27.9 Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 1

49 550 Activity: Ask students try to put the cans in order from lightest to heaviest. Then show the students which can correlates to which planet so they can see how heavy or light a can of soda would be on the different planetary objects. The goal here is for the students to make the connection that in general, the more massive the planet the larger the gravitational pull, and therefore the can will weigh more on larger planets. However, some planets which are larger than Earth, such as Saturn and Uranus, have lower gravity. This is because Saturn and Uranus have a lower average density and much greater radius than Earth. Note, the heaviest soda can goes with the largest planet. If further guidance is needed, the correlation with size and mass can be pointed out to them. It will be necessary to explain that Saturn and Uranus have similar gravities to Earth. Here is a good place to talk about the difference between mass and density. Graphing Exercise: Have the students plot of grams of a can of soda on the planet versus: 1. mass of the planets; 2. radius of the planets; 3. gravity on each planet; and 4. density of the planets (see graphs below). None of the graphs show any correlation except for the graph of grams of a can of soda versus gravity. Ask students to interpret each graph in one or two sentences. ANSWER KEY for Exercise: A Graph A is a plot of how much a can of soda would weigh on a planetary body versus the mass of the planet. The y-axis in graph A is written in scientific notation (Scientific notation, or exponential notation, is a way of writing numbers that accommodates values too large or small to be conveniently written in standard decimal notation, e.g., 5,720,000,000 = 5.72 x 10 9 ) Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 2

50 551 B Graph B is a plot of how much a can of soda would weigh on a planetary body versus the radius of the planet (data is listed in the above table). Diamond symbols represent terrestrial planets; Mercury is blue/gray diamond, Venus is a royal blue diamond, Earth is a green diamond, and Mars is a red diamond. Circles represent gas giants; Jupiter is shown as an orange filled circle, Saturn is a pale yellow filled circle, Uranus is a cyan filled circle, and Neptune is a dark blue filled circle, Pluto is shown as a white square and the Earth s Moon is a gray triangle. On the next page, Graph A is a plot of how much a can of soda would weigh on a planetary body versus the gravity of the planet and Graph B is a plot of how much a can of soda would weigh on a planetary body versus the density of the planet (data is listed in the above table). Diamond symbols represent terrestrial planets; Mercury is blue/gray, Venus is a royal blue diamond, Earth is a green diamond, and Mars is a red diamond. (Note that in graph A, Mars and Mercury plot on top of one another; Mercury s symbol is the inner, smaller diamond.) Circles represent gas giants; Jupiter is shown as an orange filled circle, Saturn is a pale yellow filled circle, Uranus is a cyan filled circle, and Neptune is a dark blue filled circle, Pluto is shown as a white square and the Earth s Moon is a gray triangle. Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 3

51 552 A B Agood website that allows students to compare masses of planets is at: n/planet_mass_comp_full.htm A Bonus Assignment is to have the student select an object and determine what it would weigh on each of the planets. This object can be themselves or anything else that they know the weight of. It may be necessary to do an example on the board, as well as give them a worksheet to fill out Two websites to check the answers to the bonus assignment are: Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 4

52 Calculating Weight on Different Planetary Objects Answer Key Student handout is printed in Part C of Unit 7 of the curriculum. Source: Your Weight on Other Worlds Answers are according to what a person who weighed 100 lbs on Earth would weigh on the other planets (and Pluto). 1. On what planet would you weigh the closest to what you weigh on Earth? Saturn, On what planet would you weigh the least? Mars, On which planet would you weigh the next least? Mercury, On what planet would you weigh the most? Jupiter, On which planet would you weigh the next most on? How does this compare with what you weigh on Earth? Neptune, and Fairly close 6. On which 2 pairs of planets would you weigh almost the same? (your answer should list 4 planets) Mercury Mars and Venus Uranus (0.1) and (1.8) Individually, calculate how much would you weigh on the other 7 planets plus Pluto if you weighed a 100 lbs on Earth. Location Mass on Earth Gravity Calculated Weight Mercury 100 X.378 = 37.8 Venus X.907 = 90.7 The Moon X.166 = 16.6 Mars X.377 = 37.7 Jupiter X = Saturn X = Uranus X.889 = 88.9 Neptune X = Pluto X.067 = 6.7 Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 5

53 NAME: 554 CLASS: Individually, calculate how much would you weigh on the other 7 planets plus Pluto, if you weighed a 100 lbs on Earth. Location Mass on Earth Gravity Calculated Weight Mercury.378 = Venus.907 = The Moon.166 = Mars.377 = Jupiter = Saturn = Uranus.889 = Neptune = Pluto.067 = After you do the calculations above, go back and look at what you answered for questions 1 6. Now that you have done the calculations would you change any of your answers? Which answers surprised you? Go back and write in your answer in a different color now that you have done the math. Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 2

54 NAME: 555 CLASS: Calculating Weight on Different Planetary Objects Working in groups, using what you have already learned in your astronomy classes, make the best educated guesses for the questions listed below. Write down a reason for your guesses. 1. On what planet would you weigh the closest to what you weigh on Earth? 2. On what planet would you weigh the least? 3. On which planet would you weigh the next least? 4. On what planet would you weigh the most? 5. On which planet would you weigh the next most on? How does this compare with what you weigh on Earth? 6. On which 2 pairs of planets would you weigh almost the same? (your answer should list 4 planets) Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 1

55 NAME: 556 CLASS: Individually, calculate how much would you weigh on the other 7 planets plus Pluto, if you weighed a 100 lbs on Earth. Location Mass on Earth Gravity Calculated Weight Mercury.378 = Venus.907 = The Moon.166 = Mars.377 = Jupiter = Saturn = Uranus.889 = Neptune = Pluto.067 = After you do the calculations above, go back and look at what you answered for questions 1 6. Now that you have done the calculations would you change any of your answers? Which answers surprised you? Go back and write in your answer in a different color now that you have done the math. Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 2

56 Name Impact Cratering Lab Class Purpose To learn about the mechanics of impact cratering, the concept of kinetic energy, and to recognize the landforms associated with impact cratering. Materials This group will need: Sand (very fine and dry) Tray (at least 24 x24 ) Colored sand/powder paint Drop cloth Screen or flour sifter Slingshot Safety goggles (one for each student) Large Protractor Ruler 10 Projectiles (7 steel and 3 other) Projectiles: 4 different sizes of steel ball bearings (sizes should range from 4 mm to 25 mm): o Four identical in size ball bearings of intermediate size (e.g., 12 mm) o Three ball bearing to complete the size range from 4 mm to 25 mm. 3 identical sized objects with different densities (e.g., large ball bearing, marble, wood or foam ball, rubber superball). Safety goggles must be worn whenever the slingshot is in use! Vocabulary Floor bowl shaped or flat, characteristically below surrounding ground level unless filled in with lava. Ejecta Blanket of material surrounding the crater that was excavated during the impact event. Ejecta becomes thinner away from the crater. Raised rim Rock thrown out of the crater and deposited as a ring-shaped pile of debris at the crater's edge during the explosion and excavation of an impact event. Walls characteristically steep and may have giant stairs called terraces. 557 Fig. 1 Illustrates the anatomy of a crater. Learn & use this vocabulary! Rays - Bright streaks starting from a crater and extending away for great distances. See Copernicus crater for another example. Central uplift - mountains formed because of the huge increase and rapid decrease in pressure during the impact event. They typically occur only in the center of craters that are larger than 40 km diameter. Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: Retrieved & adapted July 23, 2009 from: 1

57 NAME: 558 CLASS: Part I Examining the effect of impact angle on crater formation. Experiment 1 90 o impact Place the tray on the drop cloth. Fill the tray with sand, and then smooth the surface by scraping the ruler across the sand. Sprinkle a very thin layer of the colored sand over the surface (just enough to hide the sand below) using the screen or flour sifter. Divide the tray (target area) into four square shaped sections, using the ruler to mark shallow lines in the sand. In one section produce a crater using the slingshot to launch an intermediate size steel ball bearing straight down (at 90, vertical) into the target surface. The slingshot should be held at arms length from sand surface (70 to 90 cm or inches) facing straight down into the tray. Do not remove the projectiles after launch. Use the space on the following page to make a sketch of the plan (map) view and of the cross section view of the crater. Be sure to sketch the pattern of the light-colored sand around the crater. This material is called ejecta. Label the crater floor, crater wall, crater rim, and ejecta on the sketch. Sketch crater 1 here: Questions for Crater Experiment 1 1. Where did the ejecta come from? Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: Retrieved & adapted July 23, 2009 from: 2

58 NAME: 559 CLASS: 2. What would you expect to find beneath the ejecta? 3. Do you observe the ejecta to be of equal thickness concentrically around the crater? Why do you think this is so? 4. What is the ejecta distribution and thickness in relation to the crater? Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: Retrieved & adapted July 23, 2009 from: 3

59 NAME: 560 CLASS: Part I Examining the effect of impact angle on crater formation. Experiment 2 65 o impact In the next section of the target tray, produce a crater using the slingshot to launch a steel ball bearing (the same size as above) at ~65 to the surface. The angle can simply be estimated. The end of the slingshot should still be 70 to 90 cm (30-36 inches) from tray. Be certain no one is down range in case the projectile ricochets. Sketch the crater and ejecta in plan view on the space provided below. Sketch crater 2 here: Question for Crater Experiment 2 5. Is there an obvious difference between the two craters or ejecta patterns, and if so explain? Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: Retrieved & adapted July 23, 2009 from: 4

60 NAME: 561 CLASS: Part I Examining the effect of impact angle on crater formation. Experiment 3 45 o impact In the third section of the target tray, produce a crater using the slingshot to launch a steel ball bearing (the same size as above) at 45 to the surface. Again, estimate the angle. The end of the slingshot should still be 70 to 90 cm from the tray. Be certain no one is down range in case the projectile ricochets. Sketch the crater in plan view on the space provided on the following page. As above, label the parts of the crater. Sketch crater 3 here: Question for Crater Experiment 3 6. Is there an obvious difference between the three craters or ejecta patterns? Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: Retrieved & adapted July 23, 2009 from: 5

61 NAME: 562 CLASS: Part I Examining the effect of impact angle on crater formation. Experiment 4 10 o Impact In the fourth section of the target tray, produce a crater using the slingshot to launch a steel ball bearing (the same size as the previous exercise) at about 5 to 10 to the surface. Again, estimate the angle, and make sure not to hit the rim of the tray. The end of the slingshot should still be 70 to 90 cm from tray. Be sure no one is down range in case the projectile ricochets. Sketch the crater in plan view and cross section on the space provided below. Sketch crater 4 here: Question for Crater Experiment 4 Examine the sand craters and your sketches. 7. How does ejecta distribution change with impact angle? Examine the photograph of the Martian crater Orcus Patera (next page). 8. Was this a high angle or low angle impact? 9. Did the asteroid that formed Orcus Patera impact from the northeast or southwest (assume that north is up and east is to the right)? Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: Retrieved & adapted July 23, 2009 from: 6

62 NAME: 563 CLASS: Image of Orcus Patera crater on Mars, North is up and East is to the right. Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: Retrieved & adapted July 23, 2009 from: 7

63 NAME: 564 CLASS: Part II Remove the four steel ball bearings from the sand tray and thoroughly mix the sand and colored sand to produce a uniform mixture. Smooth the target surface with the ruler. The remaining experiments will be performed without a colored upper layer of sand. Divide the target area into four sections as before. Produce four craters on the smooth target surface, using the same four identical steel ball bearings as in Part I. Find the mass of one of the projectiles before launching it and enter the value in the table below. Make the first crater by dropping the projectile from a height of 10 cm (4 inches) above the surface. Measure the diameter of the crater formed, and enter the value in the table below. For the second crater, drop the projectile from a height of 2 meters (6 feet). Measure the crater diameter and enter it in the table. The third projectile should be launched with the slingshot 70 to 90 cm (30-36 inches) above the tray and with the rubber tubing pulled back slightly (extended ~3 cm or ~ 1.5 inches). Measure the crater diameter and enter it in the table. For the last crater, extend the slingshot ~15 cm (6 inches). The slingshot should still be 70 to 90 cm above tray. Measure the crater diameter and enter it in the table. Calculate the kinetic energy of each projectile and enter the values in the table. Velocity (m/sec) Mass (kg) Kinetic Energy (Nm=kg m 2 sec 2 ) Crater Diameter (cm) Shot Shot Shot 3 14* Shot 4 69* Units are given in parentheses; meters per second (m/sec), kilogram (kg), Newtonmeter (Nm) = kg multiplied by meters-squared per second-squared, centimeter (cm). * velocities are approximate Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: Retrieved & adapted July 23, 2009 from: 8

64 NAME: 565 CLASS: Part III Remove the projectiles and smooth the target surface with the ruler. Divide the target into four sections. Find the mass of each projectile and enter the values in the table below. Produce four craters by dropping 4 different sized steel ball bearings from a height of 2 meters above the target surface. Measure the crater diameter produced by each impact. Enter the projectile mass and resultant crater diameters in the table below. Calculate the kinetic energy of each projectile and enter the values in the table below. Part III Shot 1 (smallest) Shot 2 (next larger) Shot 3 (next larger) Shot 4 (largest) Velocity (m/sec) * 69* Mass (kg) Kinetic Energy (Nm=kg m 2 sec 2 ) Crater Diameter (cm) Part IV Remove the projectiles and smooth the target surface with the ruler. Divide the target into three sections. Find the mass of each projectile and enter the values in the table below. Produce three craters by dropping 3 identical size, but different mass, projectiles from a height of 2 meters above the target surface. Measure the crater diameter produced by each impact. Enter the projectile mass and resultant crater diameters in the table below. Calculate the kinetic energy of each projectile and enter the values in the table below. Shot 1 (most massive) Shot 2 (next larger) Shot 3 (least massive) Velocity (m/sec) Mass (kg) Kinetic Energy (Nm=kg m 2 sec 2 ) Crater Diameter (cm) Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: Retrieved & adapted July 23, 2009 from: 9

65 NAME: 566 CLASS: Examine the results of Parts II, III, and IV. Use the completed tables to answer the following questions. 10. How does kinetic energy of the projectile relate to crater diameter? 11. How does velocity relate to crater size? 12. How does mass relate to crater size? 13. How does the size of the projectile relate to crater size? 14. Which is the most important factor controlling the crater size; the size, mass, or velocity of the projectile? Ka Hana Imi Na auao A Science Careers Curriculum Resource Go to: 10 Retrieved & adapted July 23, 2009 from:

66 Impact Craters Data Charts 1 of :16 PM 567 Hawai'i Space Grant College, Hawai'i Institute of Geophysics and Planetology, University of Hawai'i, 1996 Impact Craters Data Charts drop height=30 cm (velocity=242 cm/s) trial 1 trial 2 trial 3 total average crater diameter crater depth average length of all rays drop height=60 cm (velocity=343 cm/s) trial 1 trial 2 trial 3 total average crater diameter crater depth average length of all rays drop height=90 cm (velocity=420 cm/s) trial 1 trial 2 trial 3 total average crater diameter crater depth average length of all rays - continue on next page - drop height=2 meters (velocity=626 cm/s)

67 Impact Craters Data Charts 2 of :16 PM crater diameter 568 trial 1 trial 2 trial 3 total average crater depth average length of all rays Go to Impact Craters Student pages. Go to Impact Craters Teacher pages. Return to Impact Craters Activity Index. Return to Hands-On Activities home page.

68 Activity: Impact Craters 1 of :16 PM Hawai'i Space Grant College, Hawai'i Institute of Geophysics and Planetology, Univeristy of Hawai'i, 1996 Key Words impact impactor ejecta Impact Craters Purpose To determine the factors affecting the appearance of impact craters and ejecta. Making an hypothesis After looking at photographs of the Moon, how do you think the craters were formed? Materials 1 pan "lunar" surface material 2. What do you think are factors that affect the appearance of craters and ejecta? tempera paint, dry sieve or sifter Preparing a "lunar" test surface balance 3 impactors (marbles or other spheres) meter stick ruler, plastic with middle depression protractor "Data Chart" for each impactor graph paper Fill a pan with surface material to a depth of about 2.5 cm. Smooth the surface, then tap the pan to make the materials settle evenly. Sprinkle a fine layer of dry tempera paint evenly and completely over the surface. Use a sieve or sifter for more uniform layering. What does this "lunar" surface look like before testing? Cratering Process 1. Use the balance to measure the mass of each impactor. Record the mass on the "Data Chart" for this impactor. 2.

69 Activity: Impact Craters 2 of :16 PM 570 Drop impactor #1 from a height of 30 cm onto the prepared surface. 3. Measure the diameter and depth of the resulting crater. 4. Note the presence of ejecta (rays). Count the rays, measure, and determine the average length of all the rays Record measurements and any other observations you have about the appearance of the crater on the Data Chart. Make three trials and compute the average values. Repeat steps 2 through 5 for impactor #1, increasing the drop heights to 60 cm, 90 cm, and 2 meters. Complete the Data Chart for this impactor. Note that the higher the drop height, the faster the impactor hits the surface. Now repeat steps 1 through 6 for two more impactors. Use a separatedata Chart for each impactor. Graph your results. Graph #1 is Average crater diameter vs. impactor height or velocity. Graph #2 is Average ejecta (ray) length vs. impactor height or velocity. Note: on the graphs, use different symbols (e.g., dot, triangle, plus, etc.) for different impactors. Results 1. Is your hypothesis about what affects the appearance and size of craters supported by test data? Explain why or why not. 2. What do the data reveal about the relationship between crater size and velocity of impactor. 3. What do the data reveal about the relationship between ejecta (ray) length and velocity of impactor. 4. If the impactor were dropped from 6 meters, would the crater be larger or smaller? How much larger or smaller? Explain your answer. (Note: the velocity of the impactor would be 1,084 centimeters per second.) 5. Based on the experimental data, describe the appearance of an impact crater.

70 Activity: Impact Craters 3 of :16 PM The size of a crater made during an impact depends not only on the mass and velocity of the impactor, but also on the amount of kinetic energy possessed by the impacting object. Kinetic energy, energy in mostion, is described as: where, m = mass and v = velocity. During impact, the kinetic energy of an asteroid is transferred to the target surface, breaking up rock and moving the particles around. 7. How does the kinetic energy of an impacting object relate to crater diameter? 8. Looking at the results in your Data Tables, which is the most important factor controlling the kinetic energy of a projectile, its diameter, its mass, or its velocity? 9. Does this make sense? How do your results compare to the kinetic energy equation? 10. Try plotting crater diameter vs. kinetic energy as Graph #3. The product of mass (in grams) and velocity (in centimeters per second) squared is a new unit called "erg." Go to Impact Craters Data Chart. Go to Impact Craters Graph. Go to Impact Craters Teacher pages. Return to Impact Craters Activity Index. Return to Hands-On Activities home page.

71 Teacher Page: Impact Craters 1 of :15 PM Hawai'i Space Grant College, Hawai'i Institute of Geophysics and Planetology, University of Hawai'i, 1996 Background Impact Craters Teacher Page Purpose To determine the factors affecting the appearance of impact craters and ejecta. The circular features so obvious on the Moon's surface are impact craters formed when impactors smashed into the surface. The explosion and excavation of materials at the impacted site created piles of rock (called ejecta) around the circular hole as well as bright streaks of target material (called rays) thrown for great distances. Two basic methods that form craters in nature are: 1) impact of a projectile on the surface and 2) collapse of the top of a volcano creating a crater termed caldera. By studying all types of craters on Earth and by creating impact craters in experimental laboratories, geologists concluded that the Moon's craters are impact in origin. The factors affecting the appearance of impact craters and ejecta are the size and velocity of the impactor, and the geology of the target surface. By recording the number, size, and extent of erosion of craters, lunar geologists can determine the ages of different surface units on the Moon and can piece together the geologic history. This technique works because older surfaces are exposed to impacting meteorites for a longer period of time than are younger surfaces. Impact craters are not unique to the Moon. They are found on all the terrestrial planets and on many moons of the outer planets. On Earth, impact craters are not as easily recognized because of weathering and erosion. Famous impact craters on Earth are Meteor Crater in Arizona, U.S.A.; Manicouagan in Quebec, Canada; Sudbury in Ontario, Canada; Ries Crater in Germany, and Chicxulub on the Yucatan coast in Mexico. Chicxulub is considered by most scientists as the source crater of the catastrophe that led to the extinction of the dinosaurs at the end of the Cretaceous period. An interesting fact about the Chicxulub crater is that you cannot see it. Its circular structure is nearly a kilometer below the surface and was originally identified from magnetic and gravity data. This activity was adapted from a cratering activity developed by Karen Nishimoto and Robin Otagaki, Punahou School. Lunar Impact Crater 572 Typical characteristics of a lunar impact crater are labeled on this photograph of Aristarchus, 42 im in diameter, located West of Mare Imbrium.

72 Teacher Page: Impact Craters 2 of :15 PM 573 Common definitions: floor bowl shaped or flat, characteristically below surrounding ground level unless filled in with lava. ejecta blandet of mateial surrounding the crater that was excavated during the impact event. Ejecta becomes thinner away from the crater. raised rim rock thrown out of the crater and deposited as a ring-shaped pile of debris at the crater's edge during the explosion and excavation of an impact event. walls characteristically steep and may have giant stairs called terraces. rays bright streaks starting from a crater and extending away for great distances. See Copernicus crater for another example. central uplifts mountains formed becuase of the huge increase and rapid decrease in pressure during the impact event. They occur only in the center of craters that are larger than 40 km diameter. See Tycho crater for another example. This Activity In this activity, marbles or other spheres such as steel shot, ball bearings, or golf balls are used as impactors that students drop from a series of heights onto a prepared "lunar surface." Using impactors of different mass dropped from the same height will allow students to study the relationship of mass of the impactor to crater size. Dropping impactors from different heights will allow students to study the relationship of velocity of the impactor to crater size. Preparation