Recent posts

The Earth’s Shadow

December 2, 2019

Today’s image comes once again from the many diagrams in BL Royal MS 16 C XII. This particular drawing illustrates how the earth’s shadow is cast by the sun. I appreciate the detail the scribe added to the sun, giving it a face complete with attitude. Read more

Tychonic Pumpkin Pie

November 28, 2019

One of my students happens to be a skilled baker. She made a special History of Science pumpkin pie for Thanksgiving. Seriously? When was the last time you saw a pumpkin pie with an image of Tycho Brahe on it? My students are great. Read more

Interesting Planetary Diagram

November 18, 2019

The standard geocentric model assumed that the planets were arranged out from the center, the earth, according to the period of revolution. On this assumption, the shorter the period, the closer the planet was to the stationary, central Earth.[1] Claudius Ptolemy ensconced the order in his Syntaxis (commonly know as… Read more

Want to learn what an astrolabe is?
Want to learn how to operate one?
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An Introduction to the Astrolabe