Parallax

This lesson introduces "pre-trigonometry," the estimate of the distance to a far-away point. Students will use "pre-trigonometry" to calcuate distance and will use the "thumb method" of estimating distances in the field and understand the reason it works. Finally, they will understand how astronomers used the diameter of the Earth's orbit around the Sun as a baseline for estimating the distance of some stars, and the meaning of "Parsec" and "light year." Educational levels: High school