Creator of the Symmetry454 CalendarWelcome to ...

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Created by Dr. Irv Bromberg, University of Toronto, Canada email icon

Menu (click on desired choice):

  1. The Symmetry454 Calendar or the Symmetry010 Calendar
    • simple perpetual solar leap week calendars
    • conserve the traditional 7-day week
    • have symmetrical equal quarters
    • start every quarter on the same weekday (every month for Symmetry454)
    • symmetrically distribute leap years at intervals that are as smoothly spread as possible
  2. The Kalendis Calendar Calculator ( Free ) version 9.837(1547) released Jan 1, 2012
  3. Why March 21st?
  4. The Lengths of the Seasons
  5. The Length of the Lunar Cycle
  6. The Duration of Twilight
  7. Solar Calendar Leap Rules
  8. The Traditional Hebrew Calendar and the Rectified Hebrew Calendar
  9. Small spreadsheet shows how to interconvert Year numbers with (Solar, Lunar, Indiction) cycle numbers
  10. The Arithmetic of the Bahá'í Calendar, and Variants (Leap Day, Leap Week, or Leap Month)
  11. Links to Geographic Name Servers (to set up User-Defined Locales in Kalendis)
  12. What's new at this web site?
CALNDR-L This page updated 7 Tevet 5772 (Traditional) = 7 Tevet 5772 (Rectified) = Jan 1, 2012 (Symmetry454) = Jan 1, 2012 (Symmetry010) = Jan 2, 2012 (Gregorian)