Electric Ptolemy

This is a marvelous thing. Paradigms collide when a Dutch astronomer builds a web page that uses Javascript to calculate the positions of the sun, moon, and planets based on Ptolemaic methods dating back to the second century AD: Almagest Ephemeris Calculator. That is to say, you will get answers as accurate as possible given the knowledge of the universe 1800 years ago. That’s way before Copernicus, way back when epicycles were the order of the day and the Earth was safely fixed at the center of the universe. Ptolemy could have worked out those epicycles much faster with Pentium-based hardware (although the IEEE sexagesimal floating fraction standard is pretty dodgy). Here’s a quote from the site.

When the web page is loaded the ephemeris calculator automatically selects the epoch date for the tables in Ptolemy’s Almagest as the default date. This corresponds with mean noon at the meridian of Alexandria on 1 Thoth 1 Nabonassar (or 26 February 747 BC in the proleptic Julian calendar, around 10h UT).

You will certainly remember that 747 BC is at or about the time that Sargon II conquered the Hittites. Remember? And then they came out with that lame sitcom about it, Sargon’s Heroes? I’m sure you remember.

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