It occurred to me as I was wrapping up this story that you could make a digital astrolabe to run on your smartphone or tablet. I did a quick search on my phone and -- would you believe it? -- there's an app for that! Check out Astrolabe Clock by TwoNineEight Software. It's free, although perhaps a little less satisfying to use than an astrolabe in its pure, analog form.
- Deakin, Michael A.B. "Hypatia and Her Mathematics." The American Mathematical Monthly. March 1994. (April 17, 2012) http://www.maa.org/pubs/Calc_articles/ma055.pdf
- Encyclopaedia Britannica Online. "astrolabe." Encyclopaedia Britannica Inc., 2012. (April 17, 2012) http://www.britannica.com/EBchecked/topic/39959/astrolabe
- Evans, James. The History and Practice of Ancient Astronomy. Oxford University Press. 1998.
- Janus. "The Astrolabe: An instrument with a past and a future." (April 17, 2012) http://www.astrolabes.org/index.htm
- Meech, Karen. "Astrolabes." Institute for Astronomy, University of Hawaii. Last updated May 12, 2003. (April 17, 2012) http://www.ifa.hawaii.edu/tops/astlabe.html
- Morrison, James E., ed. "Chaucer's Astrolabe Treatise." (April 17, 2012) http://www.chirurgeon.org/files/Chaucer.pdf
- Museum of the History of Science, Oxford. "Using an astrolabe to tell the time." (April 17, 2012) http://www.mhs.ox.ac.uk/exhibits/using-anastrolabe/
- Rees, Martin. "Universe: The Definitive Visual Guide." Dorling Kindersley Limited. 2008.
- Starry Messenger. "Western Astrolabe Tour." The Department of History and Philosophy of Science of the University of Cambridge. 1999. (April 17, 2012) http://www.hps.cam.ac.uk/starry/waslabe.html
- TED Talks. "Tom Wujec demos the 13th century astrolabe." TEDGlobal 2009. Filmed July 2009. (April 17, 2012) http://www.ted.com/talks/tom_wujec_demos_the_13th_century_astrolabe.html