Lesson Plans for Teachers

These lesson outlines are designed to help teachers incorporate Kepler's laws of planetary motion into physics and astronomy courses. They map to relevant NGSS and AP Physics standards.

Lesson 1: The Shape of Orbits (1–2 class periods)

Standards: NGSS HS-ESS1-4, AP Physics C (central force motion)

• Warm-up: Ask students what shape they think planetary orbits are. Most will say circles.
• Activity: Draw an ellipse with string and pins. Vary the eccentricity by moving the pins. Measure the semi-major and semi-minor axes.
• Discussion: Why did astronomers assume circles for so long? (Geocentric vs. heliocentric)
• Reading: Kepler's First Law and Ellipse Geometry

Lesson 2: Faster and Slower (1 class period)

Standards: NGSS HS-PS2-4

• Activity: Equal areas demonstration with paper cutouts.
• Simulation: Use the orbit simulator to watch how speed changes.
• Reading: Kepler's Second Law, Angular Momentum

Lesson 3: The Harmonic Law (1–2 class periods)

Standards: NGSS HS-ESS1-4, AP Physics 1 (gravitational calculations)

• Activity: Use the solar system data table to verify T² = a³ for all planets. Have students compute a³ and T² and see how closely they match.
• Worksheet: Orbital period worksheet
• Extension: Use the Third Law to calculate the mass of Jupiter from its moons' data.

Lesson 4: From Kepler to Newton (1 class period)

• Discussion: How Newton built on Kepler's work
• Reading: Universal Gravitation
• Assessment: Quiz

Lesson 5: Real-World Applications (1 class period)

• Topics: Kepler Space Telescope, satellite orbits, Mars missions
• Discussion: Why do launch windows to Mars only open every ~26 months?