exupero's blog

Astronomical wall calendar

For the last year or so my five year-old has enjoyed tracking daily sunrise and sunset times for our location in Michigan. I originally made him a simple table covering a few weeks, but as each list finished and he wanted another, I got more sophisticated and introduced some basic data visualization, in particular using the horizontal as a time axis and drawing black bars from midnight to sunrise and from sunset to midnight. He monitors the creep of sunrise and sunset, and has noticed that our latest sunrise occurs well before the winter solstice. He's also asked that some additional information be included: moon phases and meteor showers.

Looking forward to 2023, I decided to level up and make a complete wall calendar. Here's what I've come up with so far:

The calendar uses the standard week-by-week format of a traditional monthly calendar, but besides days the horizontal also represents time through each day, with the dark areas indicating when the sun is below the horizon. Besides sunrise and sunset times, I've drawn an analemma with a small sun at its maximum height for the day. The dates of solstices and equinoxes are given, as are the earliest and latest sunrises and sunsets around solstices.

Moon phase is also indicated, and full moons show their traditional names.

I included several tidbits about meteor showers. Besides naming a meteor shower on the date that it peaks, I also drew a spray of meteors which subtly encodes some additional information:

To see the full calendar, go here. If you'd like to print your own, enter your longitude and latitude, UTC offset during standard time, and when daylight savings starts and ends for you (if it does). Then click "Download as PDF" and save the resulting file. Most print shops should be able to print the PDF and spiral or comb bind the pages for you.

I'm sure the calendar isn't error free, so if you run into any problems, or if you have suggestions for additional features, please email me.