the Sun Through the Year
Creating an Earth/Sun Model
Students create a simple model of the Earth and sun as seen from space.
They use it to explore the sun's apparent movement across the sky over
the course of a year. They note the changes in the sun's angle. The begin
to understand that it appears lowest in the sky on the winter solstice
and highest on the summer solstice. This lays the groundwork for understanding
the reasons for seasons and for making sense of Mystery Class photoperiod
1-2 periods and then a few minutes each month
clear 2-quart bowl, large sheet of white paper taped to a piece
of cardboard or other rigid item, sharp pencil, erasable marker,
compass, crayons or colored pencils
Plan to conduct this on a sunny dry day around the 20th of September (close
to the Fall Equinox).
to imagine they are far out in space and can see the Earth and our sun.
Ask, What would you expect to see happening and why? Make four different
drawings to show what you'd see during each season. Once students
have completed this, ask, What questions do you have? Save
these for students to revisit later in the activity.
for larger image.
an X in the center of the paper to represent our Earth.
the materials outside. Find a level surface for the paper. Make sure
the location receives sunlight all day.
the bowl upside down on the paper. Ask students to imagine it's our
atmosphere. Mark an x on the center of the bottom of the bowl with
the overhead marker. Make sure the x on the paper is lined up under
the x on the bowl. Trace the edge of the bowl onto the paper to make
it easier to line up.
students use a compass to determine North for your location. Once
they've reached consensus, they should mark North on the paper and
a student touch the side of the clear bowl with the tip of the pencil
so the shadow of the pencil's tip falls on the X on the paper. Have
a partner make a dot on that spot with the marker. (They can put a
number or date beside each dot to recall the order in which they made
observations.) After each dot goes on, ask students, Where do
you predict the dot will be next month? Explain your thinking. Which
direction does the sun appear to be moving?
Note: To get accurate results, the bowl must sit
in the same location and be lined up in the same way for each monthly
this activity each month. Use one color overhead marker from September
through December and another color from January through June. If this
is done on or about the 20th of each month students will
see what happens on the fall and spring equinox and the winter solstice.
Their marks will indicate the changes in the angle of the sun throughout
Connections — Discussion and Journaling Questions
patterns did you notice over the course of the year?
would you explain them?
general statement(s) could you make about the yearly movements of
the sun and earth?
questions do you still have?
does this "tell you" about the seasons?
you noticed that the sun appeared higher
in the sky than it was a month ago, which seasons could it not
be? Explain your thinking. (It couldn't be fall, because
the sun appears lower in the sky from month to month in the fall.)
As students mark the sun's apparent movement throughout
the year, they'll find that it appears lower and lower from
the fall equinox through the winter solstice. It appears lowest
in the sky (the greatest angle) on the winter solstice and
then begins to appear higher and higher until the summer solstice,
when it's at its highest point. It is somewhere between the
two on the equinoxes. (See the glossary definitions and images
of the sun's location on the solstices
have completed the exploration, ask them to revise the drawings they
made during Laying the Groundwork. They can either create new ones or
use another color to make changes. Their responses to the discussion
and journaling questions along with the changes in their drawings should
reveal an enhanced understanding of the seasonal Sun-Earth relationship.
Also see these assessment tasks.