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Active Galaxies and the Fermi Education and Public Outreach Program 9-14 http://fermi.sonoma.edu Active Galaxies and the Fermi Education and Public Outreach Program ................... 2 National Standards Matrix ..................................................................................................... 4 Introduction to Active Galaxies ............................................................................................ 5 Activity 1: Building Perspectives with Active Galaxies 6 Student Worksheet: A Making a Model of an Active Galaxy ...................................................................... 9 B Drawing the Active Galaxy Model from Diferent Perspectives ........................ 10 Activity 2: Zooming In on Active Galaxies 11 Student Worksheet: A Testing the Small Angle Approximation ................................................................. 17 B Measuring the Angular Size of a Person ................................................................... 18 C Measuring the Angular Size of a Galaxy Using the Active Galaxies Poster ..... 20 Activity 3: Light Travel Time and the Size of Active Galaxies 22 Student Worksheet: A Finding the Size of an Active Galaxy Flare Region ............................................... 26 B Measuring the Size of an Active Galaxy Flare Region ........................................... 26 C Measuring the Energy Emitted by an Active Galaxy Flare .................................. 28 Glossary (Defnitions and Acronyms).................................................................................... 29 Detailed Standards for Each Activity .................................................................................... 31 Resources ..................................................................................................................................... 33 1 usy educators sometimes have trouble fnding Where do gamma rays come from? Bways to help their students feel the excitement of science in action. As a part of its educational Gamma-ray sources include black holes, pulsars, efort, the NASA Education and Public Outreach supernova remnants, and active galaxies. Active group at Sonoma State University (SSU) has put galaxies are a very common source of high-energy together a series of activity presentations based gamma rays detected by Fermi. Tousands of these on the science of one of NASA’s exciting space sources are being studied during its mission. missions: the Fermi Gamma-ray Space Telescope. What instruments does Fermi use? Since many students remember and understand better when they actively engage in manipulating the concepts about which they are learning, we have Tere are two scientifc instruments on board included several hands-on activities to help keep Fermi: the Large Area Telescope (LAT) and the their interest and reinforce their comprehension Gamma-ray Burst Monitor (GBM). Te LAT is the primary instrument, and surveys the sky in and retention of the scientifc concepts covered high-energy gamma-ray light. It also studies many in the presentation of the mission. We have also individual sources of gamma rays. Te GBM detects included information about Fermi, what kind gamma-ray bursts, tremendous explosions coming of objects it observes and why astronomers are from vast distances. Tese explosions are thought interested in them. To help you determine when to signal the birth of black holes. this project might be of most use to you in your science and/or math curriculum, we have included What will my students learn from these activities? a matrix of the math and science standards covered. Tis introduction to the activities includes the Tis series of activities uses active galaxies – distant answers to some frequently asked questions. galaxies with supermassive black holes in their What is Fermi? cores – as an engagement to teach basic concepts in physical science and mathematics. Te mapping of the activities to the relevant national standards is Te Fermi Gamma-ray Space Telescope is a NASA shown by the matrix on page 4, and a more detailed satellite that was launched in 2008. Fermi is an listing of the standards met by each activity can be Astrophysics Division mission within NASA’s found in pages 31 through 32. Science Mission Directorate. Astronomical satellites like Fermi are designed to explore the How are these activities organized? structure of the Universe, examine its cycles of matter and energy, and peer into the ultimate limits Page 5 has a general introduction to active galaxies. of gravity: black holes. Fermi detects gamma rays, Depending on the age and ability of your students, the highest energy light in the electromagnetic you may need to tell them about this information, spectrum. Fermi was built in collaboration have them read it, or have a few advanced students between NASA, the U.S. Department of Energy, put together a presentation to the rest of the class France, Germany, Italy, Japan, and Sweden. Te based on this introduction and other sources they project is managed from NASA’s Goddard Space may fnd. With this introduction, try to convey Flight Center in Greenbelt, Maryland. 2 the excitement of the scientists when they frst 11) Lesson adaptations that will help you cope discovered interesting phenomena related to active with special needs students. galaxies, such as the super-massive black holes at 12) An answer key that provides you with the their cores, and the high-energy jets of particles and answers to the questions given to the students, light that are sometimes emitted. and that will help you evaluate the products the Each activity has some or all of the following students may produce as a part of this activity. components to help you make it an exciting 13) Student worksheets that contain the learning experience for the students: information and directions necessary for the 1) Science concepts and estimated time. (Note: student to complete the activities. NOTE: giving time varies signifcantly for diferent age groups the students the work sheet without the appropriate and levels of science understanding.) background information and procedures will not 2) Background information specifc to this activity. only decrease the learning of the students, it may (See the suggestions above for possible ways to also cause frustration and feelings of inadequacy to present this background information.) master science principles. 3) Te “essential question” asked by the activity. 14) Detailed Standards lists that explain how each Take the time to help students understand that activity meets the specifc national science and scientists ask questions. Each activity states the mathematics standards. essential question that this activity is designed to 15) A glossary that briefy defnes each term with answer, or to help the student explore. which the student may be unfamiliar (these appear bold 4) Te materials needed to complete the activity. in letters the frst time they are used in the activity). 5) A list of abbreviations used and possible additional notes to the teacher. 16) A list defning any acronyms used. 6) Te specifc learning objectives of this activity. 17) A resource list which will help you fnd more information about the topics in the activities. 7) Te step-by-step procedures to be followed for the most efcient and efective use of the activity. Who developed these activities? 8) An assessment rubric for the activity. It is important that before you start an activity you have a clear understanding of what constitutes a Te activities and the poster that describes active successful activity. Tis assessment rubric suggests galaxies have been developed as part of the NASA ways to evaluate your students’ work in mastering Education and Public Outreach (E/PO) Program the activities’ objectives. at Sonoma State University, under the direction of Professor Lynn Cominsky. Tis guide and the 9) Transfer activities: One of our goals in science is accompanying poster can be downloaded from: to help students see science and scientifc concepts http://fermi.sonoma.edu/teachers/agn.php as tools to be used throughout their lives, not just as a small part of their education. Including transfer Contributors to this education unit also include Dr. activities afer the activity is completed will not Philip Plait, Lynda Williams, Sarah Silva, Michelle only reinforce the specifc objectives, but also help Curtis, Aurore Simonnet, Tim Graves, and Dr. your students learn to apply scientifc concepts to Mary Garrett. We would also like to acknowledge their “real lives.” input from Kara Granger and Dr. Laura Whitlock 10) Suggested extension and refection activities. to an earlier version of the frst activity, and helpful Tese help the student follow up the activity comments from Sharon Janulaw, Teena Della, with comprehension exercises so that they better Dr. Christine Royce, Dr. William Keel, Dr. Greg assimilate the information, and use the concepts Madejski, Dr. Tom Arnold, Rae McEntyre, Bruce they have learned to better understand phenomena Hemp, and Tom Estill. in everyday life. http://fermi.sonoma.edu 3 Te activities in this booklet conform to these National Science and Mathematics Education Standards (NSES and NCTM). Detailed standards met by each activity are listed on pages 31-32. 4 galaxy is a system of stars, gas, and dust Eventually, they slow to a stop due to friction with A bound together by their mutual gravity. A gas well outside the galaxy, forming giant clouds of typical galaxy has billions of stars, and some have matter that radiate strongly at radio wavelengths trillions. Although they come in
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