What can we learn from
starlight?
Bryan Chambers1, Nima Thananjeyan2, Jeff Jorgensen3
1University
Preparatory Academy, 2Logan High School, 3Arroyo High School
Essential Question/Problem
How do astronomers use light to
gather information about objects that
cannot be directly sampled?
Students will learn how spectroscopy can be
used to provide us with data and information
about distant stars. Students will need to
become familiar with the electromagnetic
spectrum and the concepts of emission and
absorption spectra as a means to address this
question.
Instructional Case Outline
Phase 1: Teach students about the
Electromagnetic Spectrum. This will be achieved
through the following:
•
•
•
•
PowerPoint lecture
with rich visuals and
a notes template
NASA film clip
“Build an EM
Spectrum” activity
Prism Lab repeating
the Herschel Infrared
Experiment and the
Ritter Ultraviolet
Experiment
Phase 2: Teach concepts of spectroscopy and
emission and absorption spectra. This will be
achieved through the following:
Learning Objectives (Science Standards)
Chemistry 1 a. Students will relate the
position of an element in the periodic table to
its atomic number and atomic mass.
Physics 4 e. Students will understand
spectroscopy by performing experiments which
demonstrate the electromagnetic spectrum
including radio waves, light, and X-rays of
different wavelengths and know their speed in
a vacuum is approximately 3×108 m/s
(186,000 miles/second).
Earth Science 1 a. Students will identify and
analyze spectra from the Sun to recognize the
Sun is a typical star and is powered by nuclear
reactions, primarily the fusion of hydrogen to
form helium.
Earth Science 2 c. Students will indicate
which elements were/are created in the Big
Bang, stars and the supernova stage of stars,
and the mechanism that produces them.
Earth Science 2 d. Students will classify
different types of stars in their life cycles and
use visual, radio, and X-ray telescopic data to
reveal those differences.
Earth Science 2 g.* Students will explain
how the red-shift from distant galaxies and the
cosmic background radiation provide evidence
for the “big bang” model that suggests that
the universe has been expanding for 10 to 20
billion years.
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•
•
PowerPoint lecture explaining the details of
spectroscopy and emission and absorption
spectra
Diffraction Grating Lab examining emission
spectra of specific elements
Case Study: group activity involving
reading and writing
Phase 3: Teach students about the life cycle of
stars and make the connection that our
understanding of the life cycle has been
developed through the use of spectroscopy. This
will be achieved through the following:
•
PowerPoint lecture detailing the life cycle of
stars with a concept map/flowchart for
students to fill out along the way
The 5 E’s
•Engagement
Each lecture will be preceded by an introductory
question to check for students’ background
knowledge and generate curiosity. Students will
be given opportunities to think/pair/share about
each major topic before a lecture. The
generative question will be referred to often
throughout the unit to reinforce the overall
theme of the unit.
•Exploration
The exploration component consists of an
inquiry-based, hands-on approach to enhance
students’ understanding of the key concepts.
Activities include:
•“Build an EM Spectrum” activity will allow for
modeling and reinforcement of concepts.
•Prism Lab will provide opportunity for analysis
and interpretation of data.
•Diffraction Grating Lab will require systematic
observation and comparison to unknowns.
•Explanation
The explanation portion will primarily revolve
around the three PowerPoint presentations. The
lectures will be scaffolded for students by
providing notes templates and flowcharts.
•Elaboration
The case study featuring the concepts of
emission and absorption spectra will provide a
different and creative way for students to
approach the material. They will share
information and ideas and ask new questions.
•Evaluation
There will be formative assessment steps taken
at several points in the unit. These will include:
• Checking the notes templates for each
PowerPoint lecture
• Pair/Share and check diagrams and
worksheets from Build EM Spectra Activity
• Collecting and grading the lab worksheets
• Collect and check each student group’s work
from the Case Study
Research-Based Instructional Strategies
•Building literacy and communication through
the Case Study
•Hands-on activities to reinforce concepts
•Scaffolding lectures with notes templates and
concept maps
•Front-loading vocabulary
•Use of grouping strategies
•Using inquiry approach to connect concepts
•Differentiated instruction
Capstone Project/Investigation and
Assessments
Students will be challenged in an evaluation
activity to compare stars’ absorption spectra to
emission spectra of particular elements and see
if the elements are present in the star.
Students will also participate in a research
jigsaw activity where they will gather known
scientific data about an actual star, create a
visual display and present their findings to the
class.
Implementation Plan and Next Steps
We need to modify the two part Prism Lab with
clearer directions and data sheets. We will share
this unit with our science department colleagues.
Resources
•Filmclip about the EM Spectrum, NASA
•The Electromagnetic Spectrum Activity Guide,
NASA
•Ritter Ultraviolet and Herschel Infrared
Experiments, NASA
•Website for Star Data, University of Illinois,
http://stars.astro.illinois.edu/sow/spectra.html#c
lass
Areas of Focus for Instructional Growth
We will work to enhance inquiry strategies in the
activities. We will also work to make sure that
learners of all ability levels have scaffolded
access to the curriculum.