21 September 2011

Rosh Hashanah, the sun, and the moon

Here's my current stab at visualizing a series of the following events:
  • sunrise, sunset
  • moonrise, moonset
  • the Hebrew calendar
  • the Gregorian calendar
I'm using the days surrounding Rosh Hashanah just for fun, and because it is upon us.

All times are one hour too early because I am not correcting for Daylight savings.

One thing to note is the new moon on 28 Elul/09-27, as can be seen from the fact that moontime and daytime are nearly centered upon each other. (I'm using "moon-time" to mean the time between moonrise and moonset.) Ideally the new moon would be on 1 Tishrei, but it doesn't always work out that way.

Another thing to note is that this period includes the day on which there is almost exactly 12 hours of light, 27 Elul/09-26. (To match the chart, below I use times in PST not PDT, i.e. I ignore Daylight savings.)
  • sunrise 0544 (5:44am)
  • sunset 1745 (5:45pm).
You might think that this day with 12 hours of light should be the equinox (09-23), but here's an explanation of why this is not the case.

Some of the many areas for improvement include adding the days of the week, using daylight savings, and solving the problem with blurry text on top of color.

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