Galileo's Telescope

Created Feb. 7, 2024 by Brent Purkaple, Kerry Magruder

This OER was designed by the OU Academy of the Lynx (oulynx.org) in conjunction with the "Galileo's World" (galileo.ou.edu) exhibition at the University of Oklahoma.

This activity is designed to be completed in 5 minutes by a typical visitor to the exhibition. For adaptations to other age levels and pedagogical settings, visit the "Galileo Telescope Cluster" below.

Introductory Galileo Telescope Activity

A telescope makes uses of both concave and convex lenses to magnify distant objects.

** The only supplies you will need for this activity are a set of concave and convex lenses. **

Warning: When performing this experiment it is important not to look toward a window, whereby you might accidentally glance toward where the light might be blinding.

Find the plano-convex lens. The plano side is flat. The convex side bulges. Look through the plano-convex lens at an object near by. Does it magnify it or make it smaller?
Find the plano-concave lens. The plano side is flat, and the concave side is indented. Look through the plano-concave lens at an object on the far side of the room. Does it magnify it or make it smaller?
Position the two lenses in a line at eye-level, with the flat sides facing toward each other. Try to focus on an object a few feet away. Hold the plano-concave lens close to your eye, and the plano-convex lens a few inches farther away. Is the object right-side-up or up-side-down?

Enjoy a pdf of this lesson:

Download: Introduction to Galileo's Telescope.pdf

Historical Background to Galileo's Telescope

The earliest known telescope was created in the beginning of the seventeenth century by Hans Lippershey. This "spyglass," as it was originally called, was an instrument whose significance was originally understood in terms of sailing. The spyglass was useful for spotting other ships as well as land features from far away.

Galileo made the telescope famous. When Galileo heard news of the telescope invented in the Netherlands he worked out the underlying geometry and crafted one of his own design. In this work, Galileo produced the first published observations of the heavens made with a telescope. His sensational discoveries included mountains on the Moon, vast numbers of previously undetected stars and four satellites of Jupiter.

See high-quality images from Galileo's book here, https://galileo.ou.edu/exhibits/starry-messenger.

Further OER's on Galileo's Telescope

Use the following OER's to further explore Galileo's Telescope.

"Telescope" from Museo Galileo website, http://catalogue.museogalileo.it/indepth/Telescope.html#200603.
"Galileo's Telescope" from Museo Galileo website, http://brunelleschi.imss.fi.it/esplora/cannocchiale/index.html.

Use the following OER's to further explore the Galileo's World exhibition.

Galileo's World iPad Exhibit Guide, itunes.apple.com/us/book/galileos-world-exhibit-guide/id1032005948?mt=1.
Galileo's World iTunes U Course, itunesu.itunes.apple.com/enroll/FDS-EYK-MRL.
Galileo's World website, galileo.ou.edu.