The Exodus Calendar: A Simple Timekeeping System for Martian Colonists
£5.00
Dennis V. Silin
2025.078.0305
DOI https://doi.org/10.59332/jbis-078-09-0305
This paper presents the Exodus Calendar, a novel timekeeping system designed specifically for future Martian colonists that combines both mathematical accuracy and practical usability. The proposed system utilizes duration of Martian northward equinox year (668.5907 sols) as its reference year length and operates on a 22-year repeating cycle consisting of ten 668-sol years (even-numbered), eleven 669-sol years (odd-numbered), and one 670-sol year (final year only). Each year contains 12 months with terrestrial names, featuring a standardized 56-sol length for all months except December, which varies between 52-54 sols depending on the year type. The calendar maintains Earth’s seven-day week structure with familiar day names, organizing each month into exactly eight weeks that consistently begin on Monday and end on Sunday. The Exodus Calendar’s primary innovation lies in its cognitive simplicity: users need only remember the even/odd year length pattern and two monthly durations. This minimal learning curve, combined with retention of familiar temporal nomenclature, addresses the psychological and practical challenges of calendar adoption in Mars colony environment. Mathematical analysis demonstrates reasonable accuracy, with an average calendar year duration of 668.5909(09) sols producing a naïve error estimate of only 2.1 × 10-4 sols annually, comparable to the Gregorian calendar’s precision, making it suitable for long-term use without frequent adjustments. The proposed epoch is provisionally set to Martian equinox of April 11, 1955, to maintain compatibility with current informal conventions of Martian timekeeping but leaves the final epoch selection open for later work. A reference implementation with Earth-Mars date conversion capabilities demonstrates the system’s practical applicability.
Keywords: Mars Colonization, Calendar Systems, Timekeeping, Planetary Astronomy, Human Factors Engineering
