Tag Archives: calendars

Shifting Time and Calendar Reform

The clocks go back tonight, as the United Kingdom switches back to Greenwich Mean Time for the winter.

This human, cultural manipulation of time reminds me of the idea of the International Fixed Calendar. This is a thirteen month calendar, with each month having 28 days. This means that days and dates always match up (the 1st of the month is always a Monday, &ct). As well as making arrangements (or any date based task easier) the International Fixed Calendar makes rent, interest, mortgage, salary and other monthly payments consistent and therefore fairer.

13 times 28 equals 364, one day short of a solar year. To solve this problem, the calendar adds an extra day that sits outside the seven day week or the thirteen month system. Since 366 day leap years would still be required to keep the calendar in sync with the Earth’s orbit, every four years you would get not one but two extra-calendrical days.

Late last year, researchers at Johns Hopkins University scored a bit of a media hit with their Hanke-Henry Calendar. They solved the 365 problem by saving up the extra days and the leap days, and then scheduling a leap weak every four or five years! I prefer the International Fixed Calendar however, because we like to compare seasonal and weather conditions year-on-year. It is important to be able to compare the same date over several years and know you are also comparing the same point in the Earth’s orbit too. Continue reading