Darian (Mars)
A proposed Martian calendar · 24 months of 28 sols
The most worked-out calendar proposed for Mars, devised by Thomas Gangale in 1985. Twenty-four months of 28 sols, every sixth docked to 27, giving a year of 668 sols against the 668.59 Mars actually takes; the shortfall is made up by leap years on a rule of its own. The week is seven sols named for the same planets ours is — Sol Solis, Sol Lunae, Sol Martis and so on — and the months alternate Latin and Sanskrit names for the zodiac, Sagittarius then Dhanus, Capricornus then Makara. Year zero opens at the Martian vernal equinox nearest the invention of the telescope in 1609, so a Darian year number is roughly the Earth years since then divided by the 1.881 a Mars year takes. Nobody keeps it — no one lives there — so it sits with the other proposals rather than the calendars in use.
In UTC at 02:02 on October 27, 2026, this calendar read 27 Sagittarius 222. The reading above is live, in your own time zone.
At a glance
- Type
- Another world’s calendar — a proposal for Mars
- Origin
- Thomas Gangale, 1985
- Year
- 668 or 669 sols
- Months
- 24, of 28 sols — every sixth cut to 27
- Week
- 7 sols, Sol Solis to Sol Saturni
- Day
- A sol: 24 hours 39 minutes 35 seconds
- Leap rule
- An extra sol in odd-numbered years, and in most years that end in 0
- Counts from
- The Martian vernal equinox nearest 1609, the year of the telescope
- Where it’s used
- A proposal — no one lives on Mars to keep it
- How it’s worked out here
- From the Mars Sol Date, by Gangale’s rules
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