Curriculum Tie:


Summary: In this activity students will use a circular coordinate grid to plot zones of auroral activity.
Materials: For teacher:
 Photos of the Northern
Lights
For each student:
Attachments
Web Sites
Background For Teachers: Auroras are the beautiful curtains of colored light that are commonly
seen in the Arctic and Antarctic regions of Earth. They have a long
history of sightings by humans for over 3,000 years. Like lightening and
earthquakes, the auroras are natural events.
Auroral light is created by interactions between the sun and Earth.
The sun is a mass of electrically charged particles (in the form of a gas).
The sun is so hot that it’s outer layers blow away in the form of solar
wind. It takes an average of three days for this wind to reach Earth. In
general, Earth’s protective atmosphere and magnetic field protect the
planet from this solar wind. Instead of penetrating our atmosphere,
particles from the sun collect around Earth and gather in a cavity called
the magnetosphere.
Energized electrons from the sun collide with oxygen and nitrogen in
Earth’s atmosphere, producing colorful arrays in Earth’s magnetosphere.
The different colors of the auroras are created depending on the
molecules and altitude of collision. A yellowgreen color is the result of
an oxygen collision at 100 km. Red auroras occurs at 300 km. Blue light
results from ionized nitrogen molecules, and a purplishred color is the
result of neutralized nitrogen molecules.
It is easy to graph the auroral zone using
angles and a geographic circular grid of the
Northern Hemisphere. This activity is a
great followup to “Tomb Robbers.” Prior to this activity, students should be familiar
with benchmark angles and the circular grid
system. They should be able to plot points
on a circular grid and estimate and draw angles with minimal error.
In this activity, students use a
circular coordinate grid to plot zones of
auroral activity.
This grid system is different than a
coordinate grid because it is circular.
Astronomers often use circular grids to
identify objects in the night sky. To locate points on a circular grid, start at
the vertex and then move out to the
latitude given by the first coordinate of
an ordered pair, then move
counterclockwise along that circle the number of degrees indicated by the
second coordinate.
Vocabulary terms used in this lesson:
angle  The opening between two straight lines that meet at a vertex,
measured in degrees.
coordinate grid  A twodimensional system in which the coordinates
of a point are its distances from two intersecting, straight lines
called axes.
coordinates  An ordered pair of numbers that identify a point on a
coordinate plane or grid.
latitude  A geographic coordinate measured from the equator with
positive values going north and negative values going south.
longitude  A geographic coordinate measured from the Prime
Meridian (0˚ longitude) with positive values going east and
negative values going west.
Attachments
Intended Learning Outcomes: 2. Become mathematical problem solvers. Instructional Procedures: Invitation to Learn
Display several photos of the Northern Lights for the students.
Use some of the following questions to guide a brief class
discussion:
 Do you recognize anything in these photos?
 Has anyone ever seen the Northern Lights?
 Where would you go to see the Northern Lights?
 How are these colors created?
 What is the connection between the Northern Lights and
mathematics?
Instructional Procedures
 Have students work alone or in pairs for this activity.
 Distribute a Where to Find an Aurora worksheet to each student.
 Have students label the latitude lines as follows:
 Next have students estimate and label the unmarked longitude
lines.
 Have students plot the points onto the geographic circular grid for
the outer ring. The points are identified as ordered pairs
(longitude, latitude).
Note: If students are doing this activity after completing “Tomb
Robbers,” you will want to point out that 0˚ begins at the
bottom of the coordinate grid and angles move from this point
in a counterclockwise direction.
 Have students connect the points in the outer ring, then plot the
points in the inner ring.
 Using the scale 1 cm = 1,400 km, have students measure the
approximate distance (width) of the ring. To have students find
the range of widths, help them take measurements of both, the
shortest and longest distances between the inner and outer rings.
 Have students color in the ring with their favorite auroral colors.
 Using an atlas and the student’s Where to Find An Aurora
worksheet, hold a class discussion on the following questions:
 Where would you travel in North America to see an aurora?
 Where is the center of the auroral oval located?
 How far is the center from the North Pole?
 What is the range in widths of the auroral oval (in
kilometers)?
 If you were located at (205˚, 65˚), where would you look in
the sky to see an aurora?
 If you were located at (290˚, 60˚), where would you look in
the sky to see an aurora?
Attachments
Extensions:
Assessment Plan: Have students complete the Southern Lights worksheet.
Bibliography: Research Basis
Joram et. al., (2005). Children’s Use of the Reference Point Strategy for Measurement
Estimation. Journal for Research in Mathematics Education, 36(1), 423.
“Mathematics educators frequently recommend that students use
strategies for measurement estimation, such as the reference point or
benchmark strategy… Relative to students who did not use a reference
point, students who used a reference point had more accurate
representations of standard units and estimates of length.” Author: Utah LessonPlans
Created Date : Feb 27 2006 13:25 PM
