This week on Looking Up Bruce Bookout takes time to explain calender reformation.
We again mark a calendar to help us break up our revolution around the sun into smaller more manageable portions. Calendars are funny things in that keeping them and naming their parts lends to strange things.
The ancient Roman calendar started on the Vernal Equinox and counted an eight day week 38 times. This equates to a ten month “year” in which each moonth started on the new moon. The ancient Romans just stopped counting winter days after the calendar stopped. Of course, this left a year falling short of a full solar cycle and it needed adjusting. How they were adjusted at first was practically, then decaying into politically, as the year’s length was shorted for rivals and lengthened for allies in office.
Greek influence started a long process of reform that resulted in beginning the year to what we now call January and adding two months. By the time we get to Julius Caesar there are twelve months but it is still in need of reforming. The influence of Caesar, brought us closer to the modern calendar by smoothing out months and adding leap days.
Previously the fifth month was called Quintilis, which is Latin for “fifth”, but was renamed to honor Julius Caesar as July. Hail Caesar!
If you’d like to take a closer look at calendars, or any of the other wonderful and amazing things in the sky, please visit csastro.org for a link to information on our monthly meetings and our free public star parties.