Lesson 17

This lesson introduces learners to how the geometry of the Solar System determines where and when planets can be observed. Through discussion, diagrams, comparison activities and practical modelling, students explore the ecliptic and zodiacal band, distinguish inferior from superior planets, predict visibility at key alignments and explain apparent retrograde motion. The lesson concludes with explicit instruction and demonstration of safe solar-observation methods. Emphasise accurate astronomical vocabulary, ask learners to justify predictions using Sun–Earth–planet positions, and reinforce throughout that the Sun must never be viewed directly without certified equipment.