Meeting Information

All the Astrolabes

September 25, 2019
American Center for Physics
College Park, MD

Date: Wednesday, September 25, 2019
*Please note that this is the fourth, rather than third Wednesday in September*

Speaker: Harold A. Williams, Montgomery College

Topic: All the Astrolabes

Time and Location: 1:00 p.m., with Q&A to follow in Conference Room C on the 1st floor at the American Center for Physics (, 1 Physics Ellipse, College Park, MD-- off River Rd., between Kenilworth Ave. and Paint Branch Parkway.

Abstract: The astrolabe, a compact instrument used to observe and calculate the position of celestial bodies before the invention of the sextant, was the most important astronomical calculating device before the invention of digital computers and was the most important astronomical observational device before the invention of the telescope. The first work of science education written in a language that may be called English (middle English, actually) was Geoffrey Chaucer's Treatise on the Astrolabe. Chaucer, who today is known principally for writing the Canterbury tales, wrote the Treatise on the Astrolabe for his ten year old son Lewis in 1387.

Biography: Dr. Harold  A. Williams has been the director of the Montgomery College Planetarium since 1990. He is also the coordinator of the Physics laboratories and the head of the Astronomy program. Originally from Jacksonville, Florida, Dr. Williams received his bachelor of science degree with a double major in physics and mathematics from Florida State University. He received his Master of Science from the State University of New York at Stony Brook and his doctorate from Louisiana State University, where he studied star formation by using 3D explicit Eulerian hydrodynamics. At LSU, Dr. Williams first started teaching astronomy and learning how to use telescopes and run a planetarium. Dr. Williams continued his star formation studies for two years after leaving LSU as a post-doctoral fellow at the Department of Terrestrial Magnetism of the Carnegie Institution of Washington.