Introduction -- Activities. Measuring the moon indirectly ; Light year as distance ; Solar system scale ; The speed of light ; How far to the star? the parallax effect ; The formation of the solar system ; Habitable zone: how distance and temperature are related ; The greenhouse effect ; Creature feature: comparing earth to Mars and Venus ; Reasons for the seasons ; Phases of the Moon -- Readings. Angular diameters ; What is a light year? ; Hubble space telescope ; Scale measurements ; The Goldilocks effect: the earth is just right ; The parallax effect ; Earth as a system ; Global warming ; The water cycle ; The greenhouse effect ; The coming climate crisis? ; Reasons for the seasons ; Phases of the Moon.