Time and Calenders on Mars, a proposal
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In an article of the jan/feb 2004 issue of the planetary report (page 10)
there was a story about time and calenders on mars. It tickled me to get
a sheet of paper and start calculating. In fact it needed more papers and
this is the (scrutinized) result.
There are 3 important constants in the Martian Time table
1) 1 mars second = 1 earth second (preserve the SI units)
2) 1 Sol = 24h39m35.2s (earth)
3) 1 mars year = 668.6 sol
[the latter 2 numbers are from the article!]
Years and leap years.
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I call 1 mars year a Mear (pronounce Mir).
1 Mear has no round number of sol's so we should introduce leapsols. In
fact we need 3 leapsols every 5 years. The formula for this is quite easy:
if ((mear %5) %2) == 0 ) => leapmear => add a leapsol.
Leapsols are added on the day just opposite to the martian new year and
will be an offical holiday (just as new year's day is).
So there exist a 5 Mear period, a quintennium, which repeats.
The number of sol in a Quintennium is 3 x 669 + 2 x 668 == 3343 sol.
Seasons and months
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1 Mear has 4 seasons called Ice, Melt, Gas and Freeze which refer to the
state of the CarbonDioxide caps on the planet.
Every season has 668/4 = 167 sol.
1 mear has 23 months of 29 days + 1 new years day (holiday)
The months are just the first 23 letters of the alphabet to remember
them easily. I did not look for good names but at least I think the J
should be Jouri (in remembrance of Jouri Gagarin). In fact it doesn't matter
how people call the months as long as they use the correct first character.
Dividing the sol.
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How is a sol divided? Recall that 1 Sol = 24h39m35.2s.
First deal with the .2 seconds => every 5 sols a sol has a leap second.
that gives us 1 sol = 24 x3600 + 39 x 60 + 35 = 88775 seconds.
88775 = 5 x 5 x 53 x 67. So it make sense to divide a sol in 25 Slices
of 53 x 67 = 3551 seconds. Almost an earth hour just a small 1.4%
difference.
This leads us to the question should we have 67 mars minutes of 53
seconds or 53 mars minutes of 67 seconds. I have no real argument for
eather but I like 67 minutes in an hour as I often need a few more minutes to get
things done, now I can have them
Note that this martian time framework would
imply 25 timezones on Mars, but that is no problem.
How about the martian week?
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As the sol and the day do not sync it is unwise to synchronize the
martian week and the earth week. So how long should a meek (martian
week) take? 7 days seems to make sense as we humans are used to it. However as the
days do not sync earth days a monday on mars will seldom be a monday on
earth (chance 1 in 7). For Martians the 5 day week is better, It matches
Deimos a bit but most important we could have every leapsecond in the
weekend (which unfortunately is only 1 day). Again I did not spend time to name
the days of the week (thumb, index, middel, ring and pink?).
Last but not least a 'phobe' as mentioned in the article is approx, half
a sol and will be used for informal purposes only, like: "I stayed in
the pub for half a phobe".
To be done.
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What still has to be done is to build an algorithm to convert earth
datetime to martian datetime. For this we should have a reference date.
A good one to remember is jan 1st 2000 is new years day Mear 0 on Mars.
In conclusion
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The martian time system is filled with primes:
- A quintenium has 3343 sol (3343 is prime.
- 3 mears out of 5 are leapmear. (3 and 5 is prime)
- Every season has 167 sols (167 is prime)
(In a leapmear one season is one sol longer)
- 1 Sol has 25 slices
(OK 25 is not a prime but at least it is the square of a prime)
- 1 maur has 67 manutes (martian minutes) (67 is prime)
- 1 Manute has 53 seconds. (53 is prime)
- every 5 sols there is a sol with a leap second. (5 is prime)
- The number of months is 23 (23 is prime)
- The number of sol in a month is 29 (29 is prime)
- 1 meek has 5 sols. (5 is prime)
Although the latter three are by choice, the children on Mars better be good in math!
Best regards,
Rob Tillaart
ps,
I cannot wait to buy a martian watch, or one with both mars and earth time
[note 28-01-2004 I noted the original text was double; so I removed one ]