One of the most consequential inventions of modern times is the telescope. Almost immediately upon turning it to the skies, Galileo made discoveries that altered our perceptions of our place in the cosmos forever: features on the Moon, the rotation of the Sun, the composition of the Milky Way, the phases of Venus, and the four large moons of Jupiter.

1.
This configuration of two lenses is called a refracting telescope (or refractor), since it only uses the refractive properties of lenses. The other major type of telescope, the reflector, uses mirrors and was invented many decades later by Isaac Newton. A reflector is more complicated than a refractor, and we are interested in simplicity in this activity.
2.
View the activity at TPT Online, https://doi.org/10.1119/1.5084934 , under the Supplemental tab.

Supplementary Material

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