Post-visit Resources
Spectroscopy:
Colors of Light
IN THE WORKSHOP SPECTROSCOPY: COLORS OF LIGHT YOUR STUDENTS USED SPECTROSCOPES TO
COMPARE THE LIGHT SPECTRA OF DIFFERENT ELEMENTS AND DISCOVERED HOW ASTRONOMERS USE THIS
INFORMATION TO DETERMINE THE COMPOSITION OF DISTANT STARS. CONTINUE THEIR EXPLORATIONS OF
LIGHT AND THE WAYS WE LEARN ABOUT THE UNIVERSE WITH THE FOLLOWING DISCUSSIONS AND ACTIVITIES.
DISCUSSION:
HOW DO WE STUDY OBJECTS IN SPACE?
TIME:
10-20 minutes
G OA L :
Review and discuss concepts encountered during the field trip.
Review the list of questions the class generated
before the field trip.
• Which questions were they able to answer?
What did they discover?
• Which questions were not answered during the
trip? What new things do they now wonder
about?
• How could they find more information about
those questions?
AC T I V I T Y:
Reflect on the students’ experiences in the
workshop.
• What things can astronomers learn about a
distant star from the light it gives off?
• Which parts of using the spectroscopes were
the easiest? Which parts were challenging?
How do you think astronomers might work
around those challenges?
COMPARING SPECTROSCOPES
TIME:
20–30 minutes to assemble spectroscopes, plus additional time for observing light sources
G OA L :
Make another simple spectroscope, compare it to the one used in the workshop,
and observe spectra of natural and artificial light sources.
M AT E R I A L S :
• Spectroscopes from the Spectroscopy
workshop
• Unneeded CDs, one per student
• Cereal or cracker boxes, any size, one per student
• Aluminum foil
• Tape
• Scissors
• Rulers with millimeter markings
• Protractors or 60o angle template
(downloadable here: http://coolcosmos.ipac.
caltech.edu/cosmic_games/spectra/angle60.gif)
• Bright light sources, preferably one fluorescent
and one incandescent
Pre-visit Resources
Spectroscopy: Colors of Light
AC T I V I T Y:
COMPARING SPECTROSCOPES
PROCEDURE:
1. Remind students of the spectroscopes they built
in the Spectroscopy workshop, and/or distribute
them again for students to observe. What
different parts does the spectroscope have?
What does each part do?
2. Invite students to examine the materials for the
second spectroscope. How do they compare to
the ones they used in the workshop? Which part
do they think each material will be used for?
3. Demonstrate and/or provide written
instructions for assembling the spectroscopes.
These instructions were adapted from the Cool
Cosmos website, http://coolcosmos.ipac.caltech.
edu/cosmic_games/spectra/makeGrating.htm.
See the site for photos of each step.
• On the top of the box, measure 3.8 cm from
one end, and draw a line straight across
the top of the box. Cut across this line
and cut off the flaps that result, leaving a
rectangular hole in one side of the box top.
This will be the viewing hole.
• From the open corner of the box, use the
protractor or template to draw a line 7.6
cm long which is at a 60o angle to the top
of the box. Repeat on the other side of the
box. Cut along both lines to create slits for
holding the CD.
• In the long side of the box opposite the slits,
cut out a rectangle the width of the box
side, starting about 1 cm from the top and
extending down about 2 cm.
http://coolcosmos.ipac.caltech.edu/cosmic_games/spectra/makeGrating.htm
• Using pieces of aluminum foil folded in
half for stability, cover the top half of the
rectangle with one piece of foil, and the
bottom half with another piece, leaving a
very thin slit between the two pieces. The
slit should be between 0.5 and 1 mm thick.
Tape the aluminum foil in place.
• Tape the top of the box closed and insert
the CD into the slits.
4. Demonstrate how to use the spectroscope
by pointing the slit at a light source and
looking at the reflected spectrum on the
CD. Invite students to practice using the CD
spectroscopes until they are comfortable
creating and viewing a spectrum with them.
5. Encourage students to look at various light
sources with both the workshop spectroscope
and the CD spectroscope and compare the
spectra produced by each. How are they
similar? How are they different? What are the
advantages and disadvantages of each?
Pre-visit Resources
Spectroscopy: Colors of Light
AC T I V I T Y:
COMPARING SPECTROSCOPES
6. Spectrum Journal—Challenge students to
use one or both spectroscopes to observe the
spectra of light sources at home and other
places they go and keep a Spectrum Journal.
Journal entries should list the location and
type of light source as well as a drawing (or
photo, if possible) of the spectrum. What
can they tell about the different light sources
based on the spectra they observe from each?
Some examples of possible light sources:
• Lamps and overhead lights at home, in
stores, etc.
• Computer and TV screens
• Yellow vs. blue/purple street lights
• Stop lights, neon signs, car headlights (with
caution!)
• Sun (should not be observed directly, but
the spectrum can be seen by pointing the
spectroscope at a white wall or piece of
paper in bright sunlight)
• Moon (easiest if moon is close to full)
REFLECTION:
• Discuss the results from students’ journals.
What similarities and differences did they find
among different light sources? Which ones
were unusual or surprising? Arrange the light
sources into groups or categories based on
their spectra.
• Look at students’ photos and drawing if
possible, and/or use the photos from this
site, which show the spectra from a CD
spectroscope of many everyday light sources:
http://www.cs.cmu.edu/~zhuxj/astro/html/
spectrometer.html
EXTENSIONS:
Additional variations for making and using CD
spectroscopes are found here. http://www.
arborsci.com/cool/spectrum-analysis-breaking-itall-down Encourage students to research other
ways to produce spectra as well and construct a
different spectrum viewer. How does it compare
to the first two? What are the advantages and
disadvantages of each? Which one do they think
is most effective for identifying substances based
on their spectra? Why?
Post-visit Resources
Spectroscopy: Colors of Light
R E S E A R C H P R OJ E C T :
THE UNIVERSE’S GOT TALENT!
TIME:
15–20 minutes to introduce project, plus time for individual presentations.
G OA L :
Investigate the formation and features of a celestial object and
create audition materials for a universal talent competition.
M AT E R I A L S :
(none)
PROCEDURE:
1. Provide a list of types of celestial objects. This
might include: asteroid, comet, planet, dwarf
planet, moon, different types of stars (red
dwarf, blue giant) galaxy, nebula.
2. Encourage students to choose one type of
object to explore further. Their research might
include answers to the following questions:
• What is this object?
• Where does it come from/ how is it formed?
• Where in the universe can it be found?
• How is this type of object related to or
different from other similar kinds of objects
(for example, how is an asteroid different
from a comet or a moon)?
• How do astronomers study this kind of
object? What kinds of tools do they use?
3. After conducting the initial research, students
should choose one example of this type of
celestial object that they think is unusual or
interesting. Challenge them to imagine that this
object is auditioning for a talent competition
show, “The Universe’s Got Talent,” and create
a poster, booklet, or audition video explaining
why their object deserves to be the next big
star of the universe. Information in the projects
should include:
• What type of object it is, how it was formed,
and where it “lives” now
• How it was discovered
• What makes this type of celestial object
different from other types of objects
• Why their specific object is unique, special,
and talented enough to be a contestant on
“The Universe’s Got Talent”!
Remind students that “audition materials” need
to be exciting enough to catch the judges’
attention, but they must not include anything
that is exaggerated or untrue, or they will be
eliminated!
4. Invite students to present their auditions to the class.
REFLECTION:
• What are some similarities and differences
between the different celestial objects students
studied? If more than one student studied
the same type of object, how do their choices
compare to one another?
• Think about the ways that celestial objects are
grouped and organized—and the ways that
some of these groupings have changed over
time. Are there other ways objects in space
could be sorted? Create a new classification
system as a class, giving each category a name
and a description of what characteristics its
members have.
Post-visit Resources
Spectroscopy: Colors of Light
AC T I V I T Y:
DETECTING INVISIBLE LIGHT
TIME:
30–45 minutes
G OA L :
Create an ultraviolet light detector using UV-sensitive beads and
test light sources to determine which give off ultraviolet light.
M AT E R I A L S :
• UV-sensitive beads (available from science and
teacher resource suppliers, as well as some
hobby and craft stores)
• Yarn or pipe cleaners
M AT E R I A L S :
• UV-sensitive beads (available from science and
teacher resource suppliers, as well as some
hobby and craft stores)
• Yarn or pipe cleaners
• Various light and heat sources, including a UV
flashlight, if possible.
• Window and/or access to outdoors
PROCEDURE:
1. Introduce the activity with a discussion of
electromagnetic energy. Show an image of
the electromagnetic spectrum as appropriate,
review the relative energies of visible colors
of light, and discuss the idea that radio waves,
heat, etc., are types of light energy whose
wavelengths are too short or long (i.e., whose
energy is too high or low) for our eyes to detect.
2. Use infrared (heat) energy as an illustration of
how these other wavelengths of light energy
can be detected even if they can’t be seen with
the eye.
• How can you tell if something is hot? What
lets you know that it is giving off heat
energy even though you can’t see it?
• Various light and heat sources, including a UV
flashlight, if possible.
• Window and/or access to outdoors
• What other indirect clues can sometimes
indicate that something is hot (for example,
steam rising from a coffee cup, or toaster
coils glowing red)?
3. To detect light energy that we can’t see,
we need something else that will react to
the energy and cause a change that we can
observe. Explain that students will be making
detectors for ultraviolet light, a type of light
energy their eyes can’t see. The detectors react
to UV light with a color change that is visible
to their eyes.
4. Make detectors by stringing 4-5 beads on a
pipe cleaner or piece of yarn. These could be
fastened into a bracelet if desired.
5. Invite students to hold the detectors under
a variety of light sources and look for any
changes. If possible, include going outside,
exploring sunny and shady locations.
Encourage students to explore any other items
they think might give off UV radiation.
Post-visit Resources
Spectroscopy: Colors of Light
AC T I V I T Y:
DETECTING INVISIBLE LIGHT
REFLECTION:
• What energy sources gave off ultraviolet light?
What other kinds of light energy did they give
off? Did any give off infrared (heat) energy?
How could students tell?
2. Encourage students to find out more about a
type of electromagnetic energy that is outside
of visible light: Infrared, ultraviolet, microwave,
radio wave, gamma ray, or x-ray.
• Is this type of energy lower energy than
visible light or higher energy?
• How is it used in astronomy?
• What types of telescopes or other tools are
needed to study this kind of energy?
• What kinds of objects can be studied using
this type of energy? What can we learn
about them?
• How is this type of energy detected and
turned into something that we can observe?
• Make a chart organizing the different sources
by the types of light energy they gave off—only
visible light, visible and heat, all three, etc. Are
there any patterns?
• What are some ways that detectors translate
energy we can’t see into something that we
can observe? Brainstorm as a class about other
things that might be used to detect non-visible
wavelengths of light.
sk students to display their findings by
A
creating a poster, diagram, or three-dimensional
model illustrating either a celestial object that
is studied with this type of energy (and what
is learned about it from this energy) or the
telescope and/or other tools used to detect it.
EXTENSIONS:
1. Investigate the portion of the
electromagnetic spectrum on the other end
of visible light—infrared—with the following
activities:
• Explore visualization of near infrared light
by creating an IR camera. There are several
ways to adapt regular digital cameras or
webcams to display infrared wavelengths.
See the link in the Resources section below
for one method.
• Create a simple heat detector (see
Resources section for one example) and
test its sensitivity.
• Use temperature-sensitive liquid crystal
sheets (available from science and teacher
resource suppliers) to detect and visualize
infrared (heat) energy.
How do the detectors in each of these activities
change a type of energy we can’t see into
something that we can see?
Post-visit Resources
Spectroscopy: Colors of Light
ONLINE RESOURCES:
• Kids Astronomy—Information and games on astronomy topics for students:
http://www.kidsastronomy.com/
• The electromagnetic spectrum and its uses in astronomy:
http://missionscience.nasa.gov/ems/01_intro.html
• An introduction to spectroscopy, how a spectroscope works, and different types of spectroscopy
used in astronomy: http://loke.as.arizona.edu/~ckulesa/camp/spectroscopy_intro.html
• Periodic table with emission spectrum of each element:
http://chemistry.bd.psu.edu/jircitano/periodic4.html
• Demonstration involving modifying a webcam to make it sensitive to infrared light:
http://www.lpi.usra.edu/education/fieldtrips/2005/activities/ir_spectrum/
• Instructions for a simple heat detector: https://explorable.com/create-a-heat-detector
• Cool Cosmos—A resource on infrared radiation and its use in astronomy, including information
for students and lesson plans for teachers: http://coolcosmos.ipac.caltech.edu/
S TA N DA R D S :
The workshop Spectroscopy: Colors of Light
and these accompanying resources support the
following elements of the Next Generation Science
Standards (http://www.nextgenscience.org/):
Core Ideas:
• Definitions of Energy: Energy can be moved
from place to place by moving objects or
through sound, light, or electric currents.
(PS3.A)
• Wave Properties: Waves are regular patterns of
motion. A simple wave has a repeating pattern
with a specific wavelength, frequency, and
amplitude. Waves of the same type can differ in
amplitude (height of the wave) and wavelength
(spacing between wave peaks). (PS4.A)
• Electromagnetic Radiation: When light shines
on an object, it is reflected, absorbed, or
transmitted through the object, depending on
the object’s material and the frequency (color)
of the light. The path that light travels can
be traced as straight lines, except at surfaces
between different transparent materials (e.g.,
air and water, air and glass) where the light
path bends. A wave model of light is useful for
explaining brightness, color, and the frequencydependent bending of light at a surface
between media. However, because light can
travel through space, it cannot be a matter
wave, like sound or water waves. (PS4.B)
• The Universe and its Stars: The sun is a star
that appears larger and brighter than other
stars because it is closer. Stars range greatly
in their distance from Earth. Earth and its
solar system are part of the Milky Way galaxy,
which is one of many galaxies in the universe.
(ESS1.A)
Post-visit Resources
Spectroscopy: Colors of Light
SCIENCE AND ENGINEERING
P R AC T I C E S :
• Planning and Carrying out Investigations: Plan
and conduct an investigation collaboratively to
produce data to serve as the basis for evidence.
Make observations and/or measurements to
produce data to serve as the basis for evidence
for an explanation of a phenomenon or test
a design solution (ES). Plan an investigation
individually and collaboratively, and in the
design: identify independent and dependent
variables and controls, what tools are needed
to do the gathering, how measurements will be
recorded, and how many data are needed to
support a claim (MS).
• Developing and Using Models: Develop a
model using an analogy, example, or abstract
representation to describe a scientific principle
(ES). Develop a model to describe unobservable
mechanisms (MS).
• Asking Questions and Defining Problems: Ask
questions that can be investigated based on
patterns such as cause and effect relationships
(ES). Ask questions that can be investigated
within the scope of the classroom, outdoor
environment, and museums and other public
facilities with available resources and, when
appropriate, frame a hypothesis based on
observations and scientific principles (MS).
• Order and Consistency in Natural Systems:
Science assumes that objects and events in
natural systems occur in consistent patterns
that are understandable through measurement
and observation.
• Analyzing and Interpreting Data: Analyze and
interpret data to make sense of phenomena
using logical reasoning (ES). Analyze and
interpret data to determine similarities and
differences in findings (MS).
• Obtaining, Evaluating, and Communicating
Information: Obtain and combine information
from books and other reliable media to explain
phenomena (ES). Integrate qualitative scientific
and technical information in written text with
that contained in media and visual displays to
clarify claims and findings (MS).
CROSSCUTTING CONCEPTS
• Patterns: Similarities and differences in
patterns can be used to sort and classify natural
phenomena. Patterns can be used as evidence
to support an explanation.
• Cause and Effect: Cause and effect
relationships are routinely identified and used to
explain change.
• Scale, Proportion, and Quantity: Time, space,
and energy phenomena can be observed at
various scales using models to study systems
that are too large or too small.