Scarlet Calendar


In order for humans to prosper on Mars a number of things are needed. Among them is a unified calendar. Right now no prefered/standard calendar exists, although there are a number of propsals. Finding none of the propsed calendars satisfactory I've become encouraged to create a new one.
The requirements I have made for the calendar were:
  • The calendar must be simple to use.
  • The calendar must resamble the Gregorian calendar as much as it is reasonably possible.
  • The calendar must use as universal naming as possible.
Threfore I propose the Scarlet Calendar as the standard Martian Calendar.


According to Wikipedia:
The average length of a Martian sidereal day is 24h 37m 22.663s (based on SI units), and the length of its solar day is 24h 39m 35.244s (the latter is known as a sol, more precisely 88,775.24409 seconds). The corresponding values for Earth are 23h 56m 04.2s and 24h 00m 00.002s, respectively. This yields a conversion factor of 1.027491 days/sol. Thus Mars's solar day is only about 2.7% longer than Earth's.
(Full article: Timekeeping on Mars)

Although many calendars insist on a different nomenclature for a Martian day (sol) I use simply Martian day, or day. I think that humans are already used to that term und using it on mars will be more natural and unforced.
  • Martian second equals 1.027491 of an Earth second.
  • Martian minute equals 60 Martian seconds or 1.027491 of an Earth minute.
  • Martian hour equals 60 Martian minutes or 1.027491 of an Earth hour.
  • Martian day equals 24 Martian hours or 1.027491 of Earth days.
  • Apart from that I believe an universal, interplantary unit of time should be established which will be exactly the same on all planets.
From this point all references to days, hours, minutes and seconds will mean the Martian time units.

Martian year

The year has 668 Martian days in a normal year and 669 in a leap year.
There are 16 months each 41 or 42 days long.
The second month of the year is the leap month which has 41 days in a normal year and 42 days in a leap year.
Leap years occur in a 5 year cycle, every second year, starting with a leap year:
year 1: leap year
year 2: normal year
year 3: leap year
year 4: normal year
year 5: leap year
then the cycle repeats
year 6: leap year
year 7: normal year
year 8: leap year
year 9: normal year
year 10: leap year

Martian months

There are 16 Martian months:
  1. Silla - 42 days
  2. Gabija - 41 days in a normal year, 42 days in a leap year
  3. Gaia - 42 days
  4. Veles - 42 days
  5. Viviana - 41 days
  6. Susanoo - 42 days
  7. Belenus - 42 days
  8. Niben - 41 days
  9. Porvata - 42 days
  10. Freya - 42 days
  11. Tenjin - 41 days
  12. Whope - 42 days
  13. Ira - 42 days
  14. Perun - 41 days
  15. Eir - 42 days
  16. Zorya - 42 days

Astronomical spring begins during Gaia.
Astronomical summer begins during Belenus.
Astronomical autumn begins during Tenjin.
Astronomical winter begins during Silla.
The names of the months were chosen after various dieties originating in different parts of the world.

Silla - Inuit primary component of everything that exists.
Gabija - Baltic goddess of fire and hearth.
Gaia - Greek goddess personifying the Earth.
Veles - Slavic supernatural force of earth, waters and the underworld.
Viviana - Lady of the lake in the Arthurian legend.
Susanoo - Japanese god of sea and storms
Belenus - A Celtic solar diety.
Niben - Abenaki diety representing summer.
Porvata - Slavic god of the woods.
Freya - Norse goddess associated with love, beauty, fertility, gold, magic, war, and death.
Tenjin - Japanese god of scholarship
Whope - Lakota goddess of peace.
Ira - Polynesian sky goddess and mother of the stars.
Perun - Slavic and Baltic god of thunder and lightning.
Eir - Norse goddess associated with medical skill.
Zorya - Slavic star guardian goddesses.


The week on Mars is exactly the same as on Earth. Also days of the week are not tied to the days of the month. So each date might be different day of the week in different years.
Some callendars insist on changing the names of the days of the week, or their amount. I believe that there is very little to justify such changes.


The current era starts on 2 December 1971 C.E. on Earth which is 1 Silla 0 A.F.L on Mars.
A.F.L. stands for After First Landing.
The date and name of the era are related to the landing of the Mars 3 lander, which was the first successful landing of an humand craft on Martian soil.

End notes

The Scarlet Calendar, as most things, is not perfect. However I think it weightens simplicty and familiarity well enough to be good for everday Martian use. Most of the information required to design this calendar was found on page by Thomas Gangale (