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Dennis Schatz
Andrew Fraknoi
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Dennis Schatz
Andrew Fraknoi
Arlington, Virginia
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Library of Congress Cataloging-in-Publication Data
Schatz, Dennis, author.
Solar science : exploring sunspots, seasons, eclipses, and more / Dennis Schatz, Andrew Fraknoi.
pages cm
Summary: "Solar Science offers more than three dozen hands-on, inquiry-based activities on many
fascinating aspects of solar astronomy. The activities cover the Sun's motions, the space weather it causes,
the measures of time and seasons in our daily lives, and much more."-- Provided by publisher.
Includes index.
ISBN 978-1-941316-07-8 (print) -- ISBN 978-1-941316-47-4 (e-book) 1. Astronomy--Experiments--Juvenile
literature. 2. Sun--Observations--Juvenile literature. 3. Sun--Experiments--Juvenile literature. 4. Sun--
Juvenile literature. I. Fraknoi, Andrew, author. II. Title.
QB46.S2592 2015
523.7078--dc23
2015031629
e-LCCN: 2015035458
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Dedication
To Alan J. Friedman,
good friend, colleague,
and mentor, who inspired
everyone he met to remember
that science is a way of
thinking, not a list of facts.
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CONTENTS
About the Authors x
Introduction xiii
CHAPTER 1 1
Understanding and Tracking the Daily Motion of the Sun
Learning Goals of the Chapter 2
Overview of Student Experiences 2
Recommended Teaching Time for Each Experience 4
Connecting With Standards 4
Content Background 7
ENGAGE
1.1. Cast Away: What Do We Think We Know? 13
1.2. Your Personal Pocket Sun Clock 16
EXPLORE
1.3. Shadow and Sun Tracking 23
EXPLAIN
1.4. Modeling the Sun–Earth Relationship 32
1.5. Noontime Around the World 36
ELABORATE
1.6. Pocket Sun Compass 43
1.7. High Noon 47
EVALUATE
1.8. Write a Picture Book for Kids 51
1.9. Where Is It Night When We Have Noon? 53
1.10. What Do We Think We Know? Revisited 57
Video Math Literacy Cross-Curricular Resources
Connections Connections Connections Connections for Teachers
59 59 60 60 63
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CHAPTER 2 67
Understanding and Tracking the Annual Motion of the Sun and the Seasons
Learning Goals of the Chapter 68
Overview of Student Experiences 68
Recommended Teaching Time for Each Experience 70
Connecting With Standards 70
Content Background 72
ENGAGE
2.1. What Do We Think We Know? 79
2.2. How Can This Be True? 81
EXPLORE
2.3. Sun Tracking Throughout the Year 84
2.4. High Noon Throughout the Year 90
EXPLAIN
2.5. Reasons for the Seasons Symposium 93
ELABORATE
2.6. Length of Day Around the World 116
2.7. Seasons on Other Planets 125
2.8. I Can’t Make It Come Out Even: Fitting Days and Years Into a
132
Workable Calendar
EVALUATE
2.9. Write a Picture Book for Kids 139
2.10. E-mail Response to “How Can This Be True?” 141
2.11. Reasons for the Seasons Revisited 143
2.12. What Do We Think We Know? Revisited 146
Video Math Literacy Cross-Curricular Resources
Connections Connections Connections Connections for Teachers
148 148 149 149 151
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CHAPTER 3 155
Solar Activity and Space Weather
Learning Goals of the Chapter 156
Overview of Student Experiences 156
Recommended Teaching Time for Each Experience 158
Connecting With Standards 158
Content Background 161
ENGAGE
3.1. What Do We Think We Know? 173
3.2. Be a Solar Astronomer 175
EXPLORE
3.3. Safe Solar Viewing: Project and Record Your Own Images of the Sun 178
3.4. Discover the Sunspot Cycle 182
EXPLAIN
3.5. How Fast Does the Sun Rotate? 196
3.6. Space Weather: Storms From the Sun 206
3.7. What Else Cycles Like the Sun? 218
ELABORATE
3.8. The Multicolored Sun: An Introduction to Electromagnetic Radiation 232
3.9. Student Detectives and the Ultraviolet Sun 243
3.10. Additional Ways of Observing the Sun Safely 250
EVALUATE
3.11. Space Weather Report 257
3.12. Predict the Next Sunspot Maximum and Minimum 259
Follow-Up (Extension) Activities for This Chapter 263
Video Math Literacy Cross-Curricular Resources
Connections Connections Connections Connections for Teachers
264 264 266 266 268
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CHAPTER 4 271
The Sun, the Moon, and the Earth Together: Phases, Eclipses, and More
Learning Goals of the Chapter 272
Overview of Student Experiences 272
Recommended Teaching Time for Each Experience 274
Connecting With Standards 274
Content Background 276
ENGAGE
4.1. Predicting What the Moon Will Look Like 288
4.2. What Do We Think We Know? 292
EXPLORE
4.3. Observing the Moon 294
EXPLAIN
4.4. Modeling the Moon 304
4.5. Modeling Eclipses 311
ELABORATE
4.6. How Often Do Eclipses Occur? 313
4.7. Why Do People Spend $10,000 to See a Total Solar Eclipse? 316
4.8. Does the Moon Rotate? 318
4.9. What Do Eclipses Look Like From a Space Colony on the Moon? 321
EVALUATE
4.10. Lunar Phases Revisited 324
4.11. What Causes Lunar Phases and Eclipses? 327
Video Math Literacy Cross-Curricular Resources
Connections Connections Connections Connections for Teachers
331 331 332 332 334
Image Credits 337
Index 341
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About the Authors
Dennis Schatz is the author of years he served as a program direc-
numerous resources for educators tor for science education at the
and museum professionals, includ- National Science Foundation. At
ing Astro Adventures: An Upper the Pacific Science Center, he codi-
Elementary Curriculum (Pacific Sci- rected Washington State LASER
ence Center 2002) and Astro Adven- (Leadership and Assistance for Sci-
tures II (Pacific Science Center 2003). ence Education Reform), a program
He is also the author of 23 science to implement a quality K–12 science
books for children that have all program in all 295 school districts
together sold almost 2 million copies in Washington State. He was also
worldwide and have been translated into 23 lan- principal investigator for Portal to the Public,
guages. These include Astronomy Activity Book an initiative to develop programs—both on-site
(Simon and Schuster 1991) and Stars and Planets and off—that engage scientists in working with
(SmartLab Toys 2004). diverse audiences to enhance the public’s under-
Dennis was a member of the five-person design standing of current science research.
team that developed the Earth and space sciences He has received numerous honors, including
disciplinary core ideas for the National Research several from the National Science Teachers Asso-
Council that are found in A Framework for K–12 ciation (NSTA): the 2009 Faraday Science Com-
Science Education, which was used to develop municator Award, the 2005 Distinguished Service
the Next Generation Science Standards. to Science Education Award, the 1996 Distin-
For many years, Dennis was the senior vice guished Informal Science Education Award, and
president for strategic programs at the Pacific the 1980 Ohaus Honorary Award for Innovations
Science Center in Seattle, Washington. For four in Science Teaching.
More information about Dennis Schatz is available at
www.dennisschatz.org.
x NATIONAL SCIENCE TEACHERS ASSOCIATION
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TO PURCHASE THIS BOOK, please visit www.nsta.org/store/product_detail.aspx?id=10.2505/9781941316078Andrew Fraknoi is the author of the online journal and magazine
Disney’s Wonderful World of Space published by the American Astro-
(an astronomy book for grades 5–7) nomical Society. The International
and is the lead author of several Astronomical Union has named
successful introductory astronomy Asteroid 4859 Asteroid Fraknoi
textbooks for nonscience majors to recognize his contributions to
(such as Voyages Through the Uni- astronomy education and out-
verse, 3rd ed., published in 2004 by reach (but he wants us to mention
Brooks-Cole/Cengage). In the 1980s, that it’s a very boring asteroid and
he also edited two books of science no threat to the Earth!).
and science fiction for Bantam. He is editor and Andrew is the winner of the 2012 Faraday
coauthor of The Universe at Your Fingertips 2.0, Science Communicator Award from NSTA, as
a collection of astronomy activities and teaching well as the 2007 Andrew Gemant Award from
resources published by the Astronomical Society the American Institute of Physics. Also in 2007,
of the Pacific that is in use in formal and informal he was selected as the California Professor of
educational institutions around the world. the Year by the Carnegie Foundation for the
He is the chair of the astronomy department Advancement of Teaching. His other awards
at Foothill College, Los Altos Hills, California, include the Annenberg Foundation Award for
and appears regularly on local and national astronomy education from the American Astro-
radio explaining astronomical developments in nomical Society and the Klumpke-Roberts
everyday language. Fraknoi was the cofounder Award for public outreach in astronomy from
and coeditor of Astronomy Education Review, the Astronomical Society of the Pacific.
For more about Andrew Fraknoi, see
www.foothill.edu/ast/fraknoi.php.
EXPLORING SUNSPOTS, SEASONS, ECLIPSES, AND MORE xi
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T
he Sun is not only the easiest astronomi- FIGURE I.2
cal object in the sky to observe, but it has Total solar eclipse showing the Sun’s
a greater influence on our lives than any corona, which becomes visible during
other cosmic object. The fundamental elements totality
of how we mark time—the day and year—are
based on the Earth’s relationship with the Sun.
The cycle of our seasons (from winter to sum-
mer and back to winter again) has to do with
the tilt of the Earth toward or away from the
Sun as a year passes.
The charged particles streaming from the Sun’s
surface (the solar wind) cause the spectacular
auroras that people travel thousands of miles and
brave the cold of northern nights to see (Figure I.1).
When these particles overload our planet’s storage
capacity, they can disrupt our radio transmissions
and interrupt electrical power distribution. As
our civilization gets more and more intercon-
nected on Earth and in space, the chances of seri-
ous problems from a storm on the Sun increase.
The unique relationship between sizes and dis-
tances in the Earth–Moon–Sun system also cause that understanding than through the kinds of
spectacular eclipses of the Sun and the Moon. eye-opening (indeed, mind-opening) experiences
Total solar eclipses that reveal the eerie glow of in this volume.
the Sun’s outer atmosphere (the corona) are so This book is specifically designed for instruc-
beautiful and rare that people travel from all over tors of grades 5–8 who teach about the Sun and
the world to witness them (Figure I.2). Moon and their cycles as well as eclipses, but
Both the new and the older science standards some of the materials could easily be adapted
suggest that students need to have a good funda- for higher grades or (informal) settings outside
mental understanding of the Sun’s effect on their of school. Throughout, we provide classroom-
daily lives. There’s no better way of providing based activities, background information, and
FIGURE I.1
(Left) Aurora (northern lights) above Bear Lake in Alaska
EXPLORING SUNSPOTS, SEASONS, ECLIPSES, AND MORE xiii
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TO PURCHASE THIS BOOK, please visit www.nsta.org/store/product_detail.aspx?id=10.2505/9781941316078FIGURE I.3
experience with the science prac-
tices and crosscutting concepts A digital rendering of the Solar Dynamics Observatory
identified in the Next Genera- satellite
tion Science Standards (NGSS).
The core of the book is a series of
student-centered learning experi-
ences that put the students in the
position of being scientists: ask-
ing questions; exploring phenom-
ena; and drawing, discussing, and
refining conclusions.
Educators who use the expe-
riences and suggested teaching
strategies in this book will involve
students in the three-dimensional
learning process recommended by
the NGSS, effectively integrating
the teaching of the disciplinary core ideas, sci-
ence practices, and crosscutting concepts related
How This Book Is Organized
to the Sun and the Moon and their motion in the The book contains four chapters, each of which
sky. Sections strategically located throughout deals with disciplinary core ideas in the NGSS:
the chapters identify especially good places to
emphasize the three-dimensional learning that 1. Understanding and Tracking the Daily
students are experiencing. Motion of the Sun: What does the Sun
In addition, we provide a variety of resources do in the sky each day, and how does that
that connect the content to best practices in math- relate to our notions of time and direction?
ematics and literacy, including the use of age-
2. Understanding and Tracking the Annual
appropriate web pages and real-time data from
Motion of the Sun and the Seasons: How
observatories and satellites, such as the Solar
does the Sun’s motion and position in the
Dynamics Observatory (Figure I.3).
sky vary throughout the year, and how
Although the first edition of this book is timed
does that relate to our ideas of a calendar
to allow teachers to prepare for the Great Ameri-
and the seasons?
can Eclipse of 2017, which will be visible through-
out the United States, the book is not tied to that 3. Solar Activity and Space Weather: What
event and will be useful for teaching about the phenomena do we observe on the surface
Sun and its effects on our culture and our under- and in the atmosphere of the Sun, and how
standing of nature in any year. do these influence what we observe and
how we live our lives on Earth?
xiv NATIONAL SCIENCE TEACHERS ASSOCIATION
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4. The Sun, the Moon, and the Earth of the core disciplinary ideas, scientific
Together: Phases, Eclipses, and More: practices, and crosscutting concepts.
How do the relationships among the Earth,
Elaborate experiences provide oppor-
the Moon, and the Sun produce solar and
tunities for students to apply their new
lunar eclipses?
level of understanding to related ques-
tions or topics.
Each chapter identifies the specific perfor-
mance expectations, disciplinary core ideas, sci- Evaluate experiences allow students
ence practices, and crosscutting concepts in the (and teachers) to gauge how well they
NGSS that are addressed in the activities. Also understand the concepts covered in
listed are connections that the experiences make the chapter.
with the math and literacy standards in the Com-
mon Core State Standards (CCSS). Each learning experience in the book provides
Learning experiences in each chapter move stu- all you need to organize, prepare, and implement
dents from initially engaging with the disciplinary it, offering the following information:
core ideas, science practices, and crosscutting
concepts to having a deeper understanding of 1. Overall concept: A general description of
each of them. These experiences follow the suc- the experience.
cessful 5E Instructional Model developed by
2. Objectives: What students will learn or
Biological Sciences Curriculum Study (BSCS; see
produce by completing the experience.
the more detailed explanation of the 5E Model,
p. xviii), dividing the experiences into the follow- 3. Materials: Everything you need to have
ing five categories: before you begin.
Engage experiences hook the students 4. Advance preparation: Important steps that
into wanting to learn more about the need to be completed before you are ready
topic and reveal their preconceptions to have the students do the experience.
about the subject.
5. Procedure: Step-by-step directions for your
Explore experiences allow students to students and you, plus answers to the
build from their preconceptions by mak- questions we suggest asking. Also included
ing observations (e.g., by viewing the are alternative approaches to deal with
Sun through special glasses [Figure I.4, different classroom structures (e.g., a self-
p. xvi]), and using the scientific practices contained classroom vs. multiple sections
to generate questions and consider new throughout the day).
ideas based on their observations.
Finally, each chapter ends with suggestions for
Explain experiences allow the teacher,
activities to connect to math and literacy concepts
via continued student discussion and
and other resources that allow for further explo-
activities, to help students develop a
ration of the concepts by students and teachers.
deeper and improved understanding
EXPLORING SUNSPOTS, SEASONS, ECLIPSES, AND MORE xv
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TO PURCHASE THIS BOOK, please visit www.nsta.org/store/product_detail.aspx?id=10.2505/9781941316078FIGURE I.4
We do not expect that every teacher will
use every experience in each chapter. The goal Students learn about safe viewing of the Sun.
is to provide you with a wealth of activities so
that you can choose the ones that best fit your
students’ developmental level, your class
structure, and your time limitations. At a min-
imum, we think it is important you include
at least one each of the engage, explore, and
explain experiences.
As students will learn using these experi-
ences, what they discover about the Sun’s
motion across the sky, the phases of the Moon,
and other astronomical phenomena will be dif-
ferent for people at different locations on the
Earth. Given that this is a publication primarily
for use in the Northern Hemisphere, some of the
experiences will need modification to be effective occasional reflection regarding students’ initial
at latitudes outside mid-Northern Hemisphere understanding of a concept and how their think-
locations (i.e., outside the continental United States ing changes after analyzing the collected data and
and southern Canada). discussion with other students and the teacher, it
always comes back to making sense of observa-
tions and data (see Figure I.5 for an example of
Use of an Astronomy Lab Galileo Galilei’s use of a notebook).
Notebook There are numerous reasons why having stu-
dents keep astronomy lab notebooks is valuable:
If you already use notebooks or journals in your
class, you can skip this explanation of their value,
• Students have a single place to document
although it is important to understand the differ-
what they have done over an extended
ence between notebooks and journals in general
period of time and across a number of
and why we refer specifically to using astronomy
science experiences. This makes it easy
lab notebooks.
to recover details that students may have
Journals are typically dominated by personal
forgotten.
reflections on what the student is currently think-
ing and how the student is reacting to what is • Students can reflect on how their
happening in his or her daily life—somewhat akin understanding of a concept has changed
to a memoir. Science notebooks hold more struc- from the beginning of a unit of study to
tured, objective descriptions of science experi- the end. This type of reflection—especially
ments and observations being made by students, written reflection—is key to deeper
plus conclusions reached based on the data col- learning (an idea well confirmed by
lected. While a science notebook also allows for research on how people learn).
xvi NATIONAL SCIENCE TEACHERS ASSOCIATION
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FIGURE I.5
• The process of keeping a contemporaneous
Drawings of the Moon from Galileo’s lab notebook mirrors what scientists do in
astronomy lab notebook their daily lives to document and reflect on
their area of research.
Although there is no one way to use notebooks,
here are a few criteria that we think are important
for creating an astronomy lab notebook:
1. Whatever you use as your notebook
(e.g., commercial spiral notebook or
composition book; student-created
notebooks from 8 ½ × 11 paper), it is
important to let the student personalize
the notebook including his or her name
on the cover along with artwork of an
astronomical nature. This can consist
of drawings made by the student or
astronomical images printed from the
internet or cut out of magazines.
2. Several pages at the beginning should be
reserved for a table of contents, which is
completed as students add material to the
notebook.
3. The pages should be numbered so material
can be easily referenced in conversations
with the teacher and other students.
• Teachers can see—and assess, if
necessary—what students have done 4. Each experience in our book suggests the
step by step and how well the students minimum material that should be included
understand the concepts being studied. in the notebooks to document what
students are doing. Sometimes this calls for
• It creates an entry point for discussion
writing directly in the notebook, and other
between student and teacher or among
times it involves attaching observations or
students, which can lead to deeper
a worksheet into the notebook. You may
understanding of the concept being studied.
wish to have students add more detail than
• Keeping the journal enhances students’ we suggest regarding the procedures they
writing skills, which support all areas of follow or to reflect more on predictions
study by them. and conclusions.
EXPLORING SUNSPOTS, SEASONS, ECLIPSES, AND MORE xvii
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TO PURCHASE THIS BOOK, please visit www.nsta.org/store/product_detail.aspx?id=10.2505/9781941316078If you are new to the use of science notebooks, If not, here are the key attributes to keep in mind
here are some of our favorite resources related to during each step of the 5E Model:
their use:
Engage
• Science Notebooks in Middle School (from
• What it is time to do: Hook the
the Full Option Science System program at
students’ interest and curiosity to learn
the Lawrence Hall of Science):
more, determine the students’ current
http://goo.gl/glnddU
understanding and preconceptions,
• Science Notebooks (Washington State and raise questions the students want
LASER [the website was formerly kept by answered.
the North Cascades and Olympic Science
• What it is not time to do: Provide
Partnership]): www.wastatelaser.org/
definitions, conclusions, or the right
Science-Notebooks/home
answer; lecture to students; or explain
• Fulwiler, B. R. 2007. Writing in science: concepts.
How to scaffold instruction to support
learning. Portsmouth, NH: Heinemann. Explore
www.heinemann.com/products/E01070.
• What it is time to do: Provide
aspx. (Read a free sample chapter at www.
opportunities to conduct and record
heinemann.com/shared/onlineresources/
observations, have students work together
e01070/chapter2.pdf.)
in research teams to compare results and
discuss their data, have students suggest
Use of the 5E Instructional conclusions based on the data, ask probing
questions of students that encourage them
Model to reflect on their thinking and redirect
The use of a learning cycle method to teaching sci- their investigations if needed, make sure
ence goes back to at least the 1960s and is based on a that everyone (including the teacher)
constructivist learning approach that emerged from is a good listener, and help all students
what research tells us about how people learn (e.g., be actively engaged in collecting and
Bransford, Brown, and Cocking 1999). There are a discussing data.
number of learning cycles used by different cur-
• What it is not time to do: Allow students
ricula, but we have settled on the 5E Instructional
to stop considering other conclusions
Model developed by the BSCS because it is one of
once a single solution is offered, give
the most studied and widely used approaches (see
students answers or provide detailed
http://bscs.org/bscs-5e-instructional-model for
explanations of how to work through a
more background).
problem, tell students they are wrong, or
If you already use a learning cycle in your
give information or facts that solve the
classroom, you can skip the rest of this section.
problem immediately.
xviii NATIONAL SCIENCE TEACHERS ASSOCIATION
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Explain Teachers across the country have found the
5Es a useful and effective way to proceed through
• What it is time to do: Encourage students
their science lessons. At first, individuals not
to explain concepts and definitions in
used to the rhythm or pace of the 5Es might get
their own words, based on justification
impatient with them, but research shows that
using data; explain concepts relying on
allowing students to learn through their own
experiments or observations; and build
investigations makes for far deeper and longer-
from students’ previous experiences and
lasting learning than just lecturing to them or
preconceptions.
showing a video.
• What it is not time to do: Accept or
propose explanations without justification or
discourage or stifle students’ explanations.
Use of Think-Pair-Share
The think-pair-share learning strategy is also
Elaborate encouraged throughout the book and is closely
aligned with the 5Es. Like the 5Es, the think-
• What it is time to do: Expect students to
pair-share sequence is based on many years of
apply the concepts, skills, and vocabulary
research regarding how people learn. It provides
they have learned to new situations; make
a mechanism for individual students to person-
additional observations and collect data;
ally reflect (think) on a question or topic, typically
and use previous learning to ask questions,
in writing, before having a discussion with a part-
design new experiments or observations,
ner or small group of students (pair). The shar-
and propose appropriate solutions.
ing allows students to further reflect on their own
• What it is not time to do: Provide and others’ thinking about a subject, often lead-
students with detailed solutions to ing to refined and improved understanding. Dif-
new problems, provide answers before ferent groups may initially come up with differ-
thorough discussion, or ignore previous ent ideas or solutions about the problem at hand.
data and evidence related to the concept. When all the groups have a chance to discuss
their thinking in front of the entire class (share), a
Evaluate wider range of ideas come to the fore. Guided by
a skillful (and not too intrusive) teacher, the class
• What it is time to do: Have students
can list, discuss, and evaluate the various ideas
demonstrate and assess their own learning
the groups have come up with and deepen every-
regarding the concepts while the teacher
one’s understanding.
assesses student progress.
• What it is not time to do: Introduce new
concepts or subjects or test for isolated
Personalizing the Use of This
vocabulary and facts. Book for Your Class
Although this book and its student handouts
can be used effectively on its own, it may also
EXPLORING SUNSPOTS, SEASONS, ECLIPSES, AND MORE xix
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TO PURCHASE THIS BOOK, please visit www.nsta.org/store/product_detail.aspx?id=10.2505/9781941316078be supplemented by a textbook, by student May you have many such experiences with your
research in a library or on the internet, and by students as you use this book.
audiovisual materials that help reinforce or
—Dennis Schatz and Andrew Fraknoi
develop concepts that are hard to visualize.
We have listed some of our favorite outside
resources throughout the book. Special Note of
We understand that different classes and
groups have different schedules. Some teachers
Acknowledgment
reading this book will have a class for most of Student activities, like the experiences in this
each day and can apportion their time in such a book, are often put forward by a number of
way that experiments can be carried out through- authors independently. One version is often influ-
out the day. Other teachers will have each class enced by other adaptations that educators try and
for only one period and—if experiments need to then report on in write-ups, conference sessions,
be continued at another time on the same day— and web pages.
may need to pool the work of several classes to We gratefully acknowledge inspiration for sec-
obtain the data needed to continue. We have tried tions of a number of these experiences from the
to take into account both kinds of classes in the talented staff of the following institutions: the
instructions, but we also appreciate that no one Stanford Solar Center; the NASA Science Missions
knows a class better than its teacher, and thus you Directorate Heliophysics Forum; the Explorato-
may want to modify our suggestions to fit your rium science museum in San Francisco; the Uni-
particular circumstances. versity of California, Berkeley, Space Sciences Lab
We also know (from our past experience lead- Center for Science Education; Hands On Optics;
ing professional development workshops for the Astronomical Society of the Pacific; the Pacific
teachers) that the readers of this book will likely Science Center; David Huestis at Skyscrapers,
find ways to improve, expand, and personalize Inc.; NASA’s Goddard Space Flight Center; the
the experiences we suggest for their students. Chabot Space and Science Center; the National
If you come up with great new ways of treat- Oceanic and Atmospheric Administration,
ing the subjects we cover or simply find a clever NASA’s Stratospheric Observatory for Infrared
modification of our suggestions, we would love Astronomy (SOFIA), and others. We are particu-
to hear from you. You can reach us by e-mail at larly grateful to Deborah Scherrer of the Stanford
dschatz@pacsci.org (Dennis) and fraknoi@fhda. Solar Center for many useful suggestions.
edu (Andrew). Finally, many thanks go to Paul Allan, coau-
Both of us were trained as astronomers and thor of Astro-Adventures II (Pacific Science Cen-
have spent our professional careers explaining ter 2003), who developed and refined many of the
the wonders of the sky and the greater universe activities that are the basis of a number of experi-
to students, teachers, museum educators, and ences in this book.
museum visitors. Nothing gives us greater plea-
sure than when someone looks up and says, “Oh,
I get it! For the first time, I get how that works.”
xx NATIONAL SCIENCE TEACHERS ASSOCIATION
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A Website for This Book
A special set of web pages to go with this book • News and resources about upcoming
has been established at the National Science eclipses and other topics related to the book
Teachers Association (NSTA) website. You can
• New ideas and reader suggestions for the
find it at www.nsta.org/solarscience.
experiences in the book
The page includes the following:
REFERENCE
• PDF versions of student forms, material
Bransford, J. D., A. L. Brown, and R. R. Cocking, eds.
templates, and handouts for the book
1999. How people learn: Brain, mind, experience, and
• An updated list of links from the book (so school. Washington, DC: National Academies Press.
that you don’t have to retype URLs)
Flares on the Sun
EXPLORING SUNSPOTS, SEASONS, ECLIPSES, AND MORE xxi
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The Sun, the Moon,
and the Earth Together
PHASES, ECLIPSES, AND MORE
C
hapters 1 and 2 focused on impor- FIGURE 4.1
tant cycles of time produced by the
An image of the Moon taken with the
rotation of the Earth on its axis and
NASA Galileo spacecraft
the revolution of Earth in its orbit around
the Sun. These determine how we measure Note the lighter rays coming from the Tycho
two key periods of our lives: the day and crater at the bottom of the Moon’s disk.
the year. This chapter adds a third cycle of
importance in astronomy (and human cul-
ture): the revolution of the Moon around
the Earth. The Moon’s cyclical motion is not
only connected to our notion of a month,
but it also produces the changing phases of
the Moon and explains why we have solar
and lunar eclipses.
EXPLORING SUNSPOTS, SEASONS, ECLIPSES, AND MORE 271
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Learning Goals of the Chapter Overview of Student
Experiences
After doing these activities, students will
Teacher note: For maximum effectiveness, the
understand the following:
first three experiences in this chapter should
1. As the Moon orbits the Earth, its position be done significantly in advance of when you
relative to the Sun changes and produces do the experiences that follow. This will allow
the different lunar phases we see. students to have 10 to 30 days to observe
the Moon on their own before doing the later
2. The lunar phases have a predictable
experiences in this chapter. This might mean
pattern over about a month’s time, going
interrupting another science unit with the first
from new Moon to waxing crescent, to first
three activities, but we assure you that the
quarter, to waxing gibbous, to full Moon, to
effectiveness of keeping a Moon observation
waning gibbous, to third quarter, to waning
journal far outweighs the short-term challenge
crescent, and back to new Moon.
of starting this chapter before finishing another
3. Solar eclipses can only occur when the science topic.
Moon is in its new moon phase.
Alternatively, you can begin your unit with
4. Lunar eclipses can only occur when the the first three experiences and then move to
Moon is in its full Moon phase. other chapters of this book, allowing for a 10-
to 30-day gap between the time you do the
5. Because the orbit of the Moon is tilted
first three experiences in this chapter and when
with respect to the orbit of the Earth, lunar
you do the rest.
and solar eclipses do not occur each month
as one might expect but instead occur in
Engage Experiences
pairs of solar and lunar eclipses around
every six months. This chapter starts with what appears to be a simple
challenge for the students: putting a series of lunar
6. While people on half of the Earth can
photographs in order by the shape of the Moon as it
see a total lunar eclipse, only people in a
would appear if they observed it over a number of
narrow path on the Earth can see a total
weeks. Because the students want to know if their
solar eclipse.
answers are correct, this experience “hooks” them
7. Because the Moon takes the same amount into observing the Moon, which ultimately leads to
of time to rotate as it takes to revolve a deeper understanding of lunar phases, the connec-
around the Earth, we on Earth only see one tion of the lunar phase cycle to our concept of the
side of the Moon. month, and the cause of solar and lunar eclipses.
• 4.1. Predicting What the Moon Will Look
Like: Students examine six photographs
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of the Moon and predict the order of the front of the room is the Sun. Each student
different phases. receives a model Moon (a small Styrofoam
ball attached to a pencil) that they use to
• 4.2. What Do We Think We Know?
explore the sequence of lunar phases they
Students discuss and record their thoughts
see as the Moon orbits the Earth.
regarding the following questions: (1) What
are the different phases of the Moon, and • 4.5. Modeling Eclipses: After students
how do the phases change throughout understand where the Moon has to be in
the month and year? (2) What causes the its orbit to see each phase, the modeling
different phases? (3) What are solar and process continues as they explore where
lunar eclipses, and what causes them? the Moon has to be to produce solar and
lunar eclipses.
Explore Experience
Elaborate Experiences
Students make their own observations of the Moon,
which they will need for the explain experiences, Students engage in additional experiences that
including the time they see the Moon, the phases reinforce and build a deeper understanding of
they see, the position of the Moon in the sky, and key the core ideas and science practices regarding the
features on the lunar surface (e.g., craters, maria). Moon’s motions and phases and the timing of
and explanation for eclipses.
• 4.3. Observing the Moon: Students begin
making basic observations of the Moon • 4.6. How Often Do Eclipses Occur? The
when it is out during the school day, teacher uses hula hoops to model the Moon’s
followed by observations in the evening orbit around the Earth and the Earth’s orbit
sky from their homes. They use the around the Sun to help students understand
data collected over a number of days to why there are typically two solar eclipses
conclude how the Moon’s phases and its and two lunar eclipses each year.
position in the sky change over time.
• 4.7. Why Do People Spend $10,000 to
See a Total Solar Eclipse? Students use
Explain Experiences
the Earth–Moon–Sun model to discover
Building from their lunar observations, students that the shadow of the Moon only covers
create a model with their heads (the Earth), a a small portion of the Earth (the student’s
bare lightbulb (the Sun), and a Styrofoam ball head), leading to the realization that people
(the Moon) to understand what causes the lunar who want to see a solar eclipse often need
phases and solar and lunar eclipses. to travel to elsewhere in the world to do
so. Students then play with the model to
• 4.4. Modeling the Moon: This activity discover that this is not true for a lunar
builds on the modeling activities from eclipse: The entire half of the Earth facing
Chapters 1 and 2 in which the students’ toward the Moon will see a lunar eclipse.
heads are the Earth and a lightbulb in the
EXPLORING SUNSPOTS, SEASONS, ECLIPSES, AND MORE 273
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• 4.8. Does the Moon Rotate? Many people would see the shape of the Moon if they
believe that the Moon does not rotate observed it over a month’s time.
because we always see the same side of
• 4.11. What Causes Lunar Phases and
the Moon facing the Earth. Students use
Eclipses? Students are asked to label a
a model in which students’ heads are the
diagram that shows the Earth, Sun, and
Moon and Earth to determine whether or
Moon to indicate where the Moon is in its
not the Moon rotates.
orbit to produce each phase and to note
• 4.9. What Do Eclipses Look Like From a where the Moon must be in its orbit to
Space Colony on the Moon? Students use produce solar and lunar eclipses.
their Earth–Moon–Sun model to predict
what they would see during a solar eclipse
if they were astronauts at a Moon base.
Recommended Teaching Time
They then use internet resources to see for Each Experience
simulations of this as well as observations
Table 4.1 shows the amount of time needed for
made from the International Space Station
each experience.
that show what astronauts there see during
solar and lunar eclipses.
Connecting With Standards
Evaluate Experiences
Table 4.2 (pp. 276–277) shows the standards cov-
These experiences allow both students and teach- ered by the experiences in this chapter. Chapter 2
ers to assess how well the students understand dealt with any phenomena associated with sea-
the key ideas presented in the chapter. sons and the seasonal changes related to the appar-
ent motion of the Sun in the sky, so this chapter
• 4.10. Lunar Phases Revisited: Students are emphasizes the cyclic patterns of lunar phases
given a new set of six photographs of the and eclipses. Additionally, this table does not give
Moon and are asked to repeat the process Common Core State Standards, but gives general
of predicting the order in which they connections to the language arts and mathematics
standards.
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TABLE 4.1
Recommended teaching time for each experience
Experience Time
Engage experiences
4.1. Predicting What the Moon Will Look Like 45 minutes
4.2. What Do We Think We Know? 45 minutes
Explore experiences
4.3. Observing the Moon 45 minutes for introduction of experience,
followed by 10 minutes each day for follow-
up observations; requires students to make
observations outside of class time and a number
of days with clear weather; summing up of what
students learn takes another 45 minutes
Explain experiences
4.4. Modeling the Moon Two 35-minute periods
4.5. Modeling Eclipses 45 minutes
Elaborate experiences
4.6. How Often Do Eclipses Occur? 45 minutes
4.7. Why Do People Spend $10,000 to See a Total 45 minutes
Solar Eclipse?
4.8. Does the Moon Rotate? 45 minutes
4.9. What Do Eclipses Look Like from a Space 45 minutes
Colony on the Moon?
Evaluate experiences
4.10. Lunar Phases Revisited 45 minutes
4.11. What Causes Lunar Phases and Eclipses? 30 minutes
EXPLORING SUNSPOTS, SEASONS, ECLIPSES, AND MORE 275
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TABLE 4.2
Chapter 4 Next Generation Science Standards and Common Core State
Standards connections
Performance • MS-ESS1-1: Develop and use a model of the Earth–Sun–Moon system
expectations to describe the cyclic patterns of lunar phases, eclipses of the sun and
moon, and seasons.
Disciplinary core ideas • MS-ESS1.A: (The Universe and Its Stars) Patterns of the apparent
motion of the Sun, the Moon, and stars in the sky can be observed,
described, predicted, and explained with models.
Science and engineering • Develop and use a model to describe phenomena (e.g., model of the
practices Earth–Moon–Sun system).
• Analyze and interpret data to determine similarities and differences in
findings (e.g., daily observations of the lunar phases are compared with
observations of others and to the student’s own prediction).
• Engage in argument from evidence (e.g., discussion of which order of
the lunar phases is the most appropriate).
Crosscutting concepts • Patterns can be used to identify cause-and-effect relationships (e.g.,
observations of the Moon’s phases and modeling of the Earth–Moon–
Sun relationship reveals what causes the lunar phases).
• Science assumes that objects and events in natural systems occur in
consistent patterns that are understandable through measurement
and observation (e.g., the pattern of lunar phases is revealed though
observations of the Moon).
• Systems and system models (e.g. use of Earth–Moon–Sun model to
understand the cause of lunar phases and eclipses).
Content Background on a regular cycle. The differing amounts of light
and dark on the face of the Moon are called its
The Phases of the Moon
phases, and they repeat every 29.5 days with
Earth’s natural satellite (which we call the Moon clockwork regularity.
with a capital M, to distinguish it from the moons Since the Moon is a world made of cold rock,
of other planets) is the only object we can see in the it produces no light of its own. Moonshine, as
sky with just our eyes that changes its appearance the ancient Greeks figured out, is really reflected
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Table 4.2 (continued)
Connections to the • Writing: Students write arguments that support claims with logical
Common Core State reasoning and relevant evidence, using accurate, credible sources and
Standards demonstrating an understanding of the topic or text. The reasons and
evidence are logically organized, including the use of visual displays as
appropriate.
• Speaking and listening: Students engage effectively in a range of
collaborative discussions (one-on-one, in groups, and teacher-led)
with diverse partners, building on others’ ideas and expressing their
own clearly. Report on a topic or text or present an opinion, sequencing
ideas logically and using appropriate facts and relevant, descriptive
details (including visual displays as appropriate) to support main ideas
or themes.
• Reading: Students quote accurately from a text when explaining what
the text says and when drawing inferences from the text. Students
determine the meaning of general academic and domain-specific words
and phrases in a text relevant to the student’s grade level.
• Mathematics: Students recognize and use proportional reasoning to
solve real-world and mathematical problems. Students summarize
numerical data sets in relation to their context, including reporting
the number of observations and describing the nature of the attribute
under investigation, including how it was measured and its units of
measurement.
sunshine. Therefore, to understand the cycle of the is this sequence of phases that this chapter helps
Moon’s phases, we must look at the relationship— students to understand (Figure 4.2, p. 278).
in the course of a month—between the Earth, the
Moon, and the Sun.
The Surface Features of the Moon
For example, when the Sun is shining on the
side of the Moon facing the Earth, we on Earth In a very general way, the surface of the Moon
see the Moon lit up with sunshine—what we call can be divided into two types of terrain, the dark
a full Moon. On the other hand, when the Sun is round maria and the lighter highlands (Figure 4.3,
shining only on the side of the Moon facing away p. 279). The word maria is Latin for “seas,” a
from the Earth, we see no reflected sunlight from designation that dates from centuries ago when
the Moon—what we call new Moon. Between early Moon observers thought that the shadowy,
those two phases, we see some part of the side of round regions were quiet, dark oceans. Today
the Moon facing us lit up and some part dark. It we know the maria (pronounced “mar-ee-ah”)
EXPLORING SUNSPOTS, SEASONS, ECLIPSES, AND MORE 277
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FIGURE 4.2
A diagram of the Moon phases showing the full Moon and new Moon
First quarter
Waxing
Waxing Waxing
gibbous crescent
Full New Sun
Earth
Waning Waning
gibbous crescent
Wa
n in g
Third quarter
The outer circle of Moon diagrams shows what is visible in the sky from Earth. The inner
circle of Moon diagrams shows what would be visible from space, looking down from
above the Earth–Moon system.
are where overlapping round impact craters The Moon is full of craters—depressions made
were flooded with darker lava from beneath the when chunks of rock or ice hit the Moon and
Moon’s surface. Maria is the plural of mare (pro- explode with the energy of impact. Such explo-
nounced “mah-ray”). sions carve out a round hole in the surface of the
The highlands get their name from the fact that Moon roughly 10 to 20 times the size of the object
they are at a somewhat higher altitude than the that exploded. Younger craters tend to be brighter,
maria. It is the contrast of the dark maria with the as their impact exposes material that has not yet
lighter highlands that has inspired many genera- been covered by the darker Moon dust that blan-
tions of Moon watchers to imagine that they can kets so much of our natural satellite. You can see
see familiar shapes on the side of the Moon facing some large, young craters in Figure 4.3, including
us, including a man in the Moon, a lady’s face, Tycho and Copernicus (also see the "Lunar Map"
two children, and animals (Figure 4.4). on p. 300). On good photographs of the Moon, you
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FIGURE 4.3 FIGURE 4.4
A photo of the Moon with major features People imagine they can see various
labeled (see p. 300 for a larger version) faces and animals, such as a rabbit, in
the shapes on the Moon.
FIGURE 4.5
can see that the shapes of the dark maria all consist
of combinations of big craters that were made long Rays from a crater on the Moon
ago when giant chunks of rock were still common
in the inner solar system.
Depending on the size and nature of the explo-
sion that forms a crater, good-sized chunks of
exploded rock can be thrown sideways away
from the site of the explosion. When these pieces
fall, approaching the surface and scraping along
it before coming to a rest, they leave lighter
streaks along their paths. Called rays, some of
these features on the Moon can extend dozens or
even hundreds of miles from the original crater,
but they all point back to the original explosion
On this image of the Moon taken by the
that produced them. Rays from the crater Tycho
Clementine spacecraft, the bright crater Tycho
are easily seen on photos of the Moon that show
has rays coming out of it in many directions.
good detail (Figure 4.5).
EXPLORING SUNSPOTS, SEASONS, ECLIPSES, AND MORE 279
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FIGURE 4.6
An illustration of the Moon’s orbit relative to the Earth and Sun
Full Moon 1
Moon’s location
after an orbit of
360º
27.3 Days
Full Moon 2
29.5 Days
It takes two extra days for the Moon to go from full Moon to full Moon compared with the time it takes to
complete one full orbit (360°) of the Earth because the Earth is also orbiting the Sun. Thus, the Moon has
to revolve more than 360° to get back in line with the Earth and Sun, which is required to see a full Moon.
The Month and the Motions That phases of the Moon take about 29.5 days to repeat
Define It (Figure 4.6). It is this cycle of repeating phases that
has given its length to the unit of time we call the
The Moon takes 27.3 days to orbit (revolve around) month, a term that is based on the word Moon.
the Earth—that is, to return to the same place rela- The cycle of the Moon’s phases over 29.5
tive to the stars. However, the Earth–Moon sys- (roughly 30) days has been one of the fundamen-
tem is also revolving around the Sun during that tal elements of timekeeping in human history.
time, which means that the relative position of the Since the Moon is easy to see and remember, it is
three bodies is slowly changing. This is why the simple to keep track of the cycle. Many cultures
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