05. Geometry of Orbiting Satellites
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Worksheet

The Geometry of Orbiting Satellites

Grade Level:

9 – 12

Curriculum Standards:

SI-H-A-3, SI-H-B1, PS-H-A1, ESS-H-D2, ESS-H-D6

Technology Level:

Limited-Moderate

Overview:

By drawing a circle and different ellipses, students will model the elliptical path that a satellite follows as it orbits the earth and make measurements to explain the construction and shape of an ellipse.

Purpose:

This lesson is to explore the motion of a satellite in space as it orbits a larger celestial body.

It is to show how Kepler’s Laws explain both the motion of planets around the sun and the motion of all orbiting satellites, including artificial satellites around the earth.

Objectives

At the conclusion of this lesson , the student will be able to:
  1. Explain the difference between the construction of a circle and an ellipse.
  2. State Kepler’s 3 Laws of Planetary Motion and use them to explain the orbit of any planet around the sun.
  3. Use Kepler’s 3 Laws to explain the orbit of any satellite around the earth.
  4. Recognize that satellites move in elliptical orbits around the earth, and identify the points called the perigee and the apogee.
  5. Define eccentricity of an ellipse and identify the relationship between eccentricity and the distance between the two foci.

Materials and Resources:

Each student or group of students will need a thick piece of cardboard or Styrofoam (thick enough to secure a thumbtack), paper to cover the board and make drawings, metric ruler , and a piece of string approximately 60 cm long. Each student should be given the student worksheet that follows.

Internet Sites:

Procedures:

See student worksheet that follows

Evaluation:

  1. Students can be assessed on the completion and accuracy of the student worksheet.
  2. Students can answer test questions concerning Kepler’s 3 Laws as they relate to an orbiting satellite, circles, ellipses, apogee, perigee, and eccentricity.

Extensions:

  1. Students can make additional measurements to determine the semi-major axis(1/2 the longest distance across the ellipse) and the distance between the center of the ellipse and the focus.
  2. Students can use these measurements to calculate the eccentricity of each ellipse.
    eccentricity = semi-major axis / displacement of focus from center