The Martian Calender and Timekeeping

clark · 2004-01-21 14:37:17

This is indeed a valid point, as long as you propose to live in your bubble forever.

We all live in our own bubbles...

Here's a question about time on Mars:

How many time zones are there? What is the size of the time zone? How is the extra 30 minutes handled with time zones? Where should the "Greenich", or start time for Mars, be located?

I think trying to match Earth seasons and Mars seasons may be overly difficult- Mars has longer years, longer days. Eventually it will stop matching, unless you have floating seasons that change from one year to the next.

Palomar · 2004-01-21 15:13:38

*I'm sure most of us know the difference between physical bubbles (aka "domes") and metaphorical bubbles.

--Cindy

P.S.: Shaun wrote previously: "and that old phrase: '24 hours a day, 668 days a year' ... Oops! Oh well, I guess you can't have everything!!"

That's good. :laugh:

It is interesting, isn't it, how this thread generated so much controversy in its early days. Wish I had a few more suggestions...hmmmmm...

Byron · 2004-01-21 17:02:55

How many time zones are there? What is the size of the time zone? How is the extra 30 minutes handled with time zones? Where should the "Greenich", or start time for Mars, be located?

If there are ever enough settlements on Mars to warrant multiple time zones, I think it would make sense to have 12 different timezones (in 2 hour increments) instead of 24, just to make things a bit simpler. As for the "extra" minutes, I think the Martians will do what the JPL scientists are doing right now... using a "Martian" time in which the seconds, minutes and hours are about 3% longer than Earth time. KSR's cute "timeslip" idea may have been a fun writer's tool for his books, but I honestly don't see the practicality of stopping the clock 39.5 minutes each night just to stay on Terran time. Why not just make the units of time fit the slightly longer day?

It's all a matter of using a little common sense about these sorts of things....

B

Palomar · 2004-01-22 06:24:11

*Maybe the year "problem" could be solved by considering 1 year as being from perihelion to aphelion and another (new) year as being from aphelion to perihelion.

--Cindy

Byron · 2004-01-22 07:13:06

Here is the definition of the second:
the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom
I guess most scientist would have something to argue if instead of 9,192,631,770 periods, we would have on Mars 9,468,410,723, cause most formulas and constants in physics will get screwed up.

I'm not suggesting that we throw the baby out with the bathwater. Of course, the Terran "second" would remain the standard yardstick for scientific purposes, etc. The Martian second would be used solely for convenient timekeeping, i.e., keeping the 60-60-24 division of time that ALL people are accustomed to using. As for the "incompatibility" issues using two different units of time...that's just one of the things people will have to learn to live with, such the communications lag between Earth and Mars, etc.

B

clark · 2004-01-22 07:24:06

Cindy, excellenct idea.

Mars rise, Mars fall.

The second should just be the second, let's not confuse the future any more than is neccessary.

A simple digital watch that can be clicked to display current Earth time and date (with the day abbreviation) is all that they really need. Just like those watches that can display ten different 'curren time' for different world cities.

Perhaps we should take a cue from that 50k pen myth, and do what any Russian might, just figure out what works.

dickbill · 2004-01-22 10:05:23

I still believe that an universal representation of the time in a linear form is necessary. That way, it is the same time on MArs, whatever the longitude, or earth or luna or anywhere in the universe, provided you are not in a spaceship at close lightspeed.
Since it is linear, it could be decimaled too, but not necesseraly. The unit would be the second. We just have to initialize an origine of the "time", somewhere in the future and standardize a representation on a watch like :
00:00:04:03:05:05:01:04:08:01
which could be approximate by
04::::::: a little bit more than a year
a year is
00:03:01:07:00:08:08:00:00:
about 31.7 millions seconds

Byron · 2004-01-22 10:31:11

I still believe that an universal representation of the time in a linear form is necessary. That way, it is the same time on MArs, whatever the longitude, or earth or luna or anywhere in the universe, provided you are not in a spaceship at close lightspeed.
Since it is linear, it could be decimaled too, but not necesseraly. The unit would be the second. We just have to initialize an origine of the "time", somewhere in the future and standardize a representation on a watch like :
00:00:04:03:05:05:01:04:08:01
which could be approximate by
04::::::: a little bit more than a year
a year is
00:03:01:07:00:08:08:00:00:
about 31.7 millions seconds

Hmmmm....this looks to be awfully complicated. Can't make heads or tails of what you're suggesting... ??? (sorry...)

I think the Gregorian calendar will be used as the "universal yardstick" of measuring time, and other systems layered on top of it simply as a matter of convenience.

B

dickbill · 2004-01-22 10:50:42

I think the Gregorian calendar will be used as the "universal yardstick" of measuring time, and other systems layered on top of it simply as a matter of convenience.
B

this is not complicated, you just add the seconds passed since the origine of the time, defined arbitrarily.
A year is about 31 millions seconds, written with 7 digits in decimal system, so 10 years after its creation, this calendar needs 8 digits, 9 after 100 yers etc.
That is not too much on a watch and It's really universal. The year unit and the days, months weeks etc, are not universal and would be useles in a standard time in a populated solar system. It's like everything when you get used to it.

I don't know, but how the southern hemisphere people feel about celebrating christmas in summer or the fact that we are, officially, in winter ?

This doesn't mean a local time is useless, of course.

A.J.Armitage · 2004-01-27 22:03:58

Well, just a quick thought on Holidays.
Martian Holidays will likely include...
1. Some sort of Holiday to Commemorate the first human landing on Mars. Happy First Landing all!

2. Days named in Honour of Mars probes.
For instance: Today is the first Viking Day! (Where we all dress up like vikings, drink beer and wrestle!-Think a St. Patrick's Day that had a train wreck with a Renaissance faire or three)
On Pathfinder day, we all run about. On the day of Spirit, we do extreme sports in commemoration of that first bouncy re-entry.
3. Other national holidays as needed.

Why in the world would they celebrate probes? It's like Zubrin's idea to put the Martian epoch several decades ago so that all the probe dates will be in positive numbers. Who cares? 100 years from now they'll barely register as historical curiosities.

(On the other hand, holidays based on failed probes where you smash into stuff and fall over might be fun.)

Holidays are more likely to be on the solstices and equinoxes and on perihelion and aphelion.

Bill White · 2004-01-27 22:55:45

I have started notes for a book tenatively titled "St. Bob's Day" to be celebrated by the Marsians on the Terran anniversary of Robert Zubrin's book.

St. Bob's Day. Wonder if he would approve?

clark · 2004-01-28 10:48:50

Every cult needs a deity.

We can light red, blue, and green candles.

good idea for a story, but please don't use Zubrin.

Bill White · 2004-01-28 11:03:07

Every cult needs a deity.
We can light red, blue, and green candles.
good idea for a story, but please don't use Zubrin.

The whole book takes place on one single day - - Marsian sunrise to sunset - - and examines the settlement and settlers in detail. Flashbacks and flashforwards give context.

St Bob's Day strikes me as pretty funny, but maybe that is just me. I have also named a fictional space vessel the Secy General Hillary Clinton - - its a research vessel that accomplishes humanity's first jump into hyperspace.

Saint Bob ?! That's preposterous. And which church do you think will make him a saint ?!

Its a "tongue in cheek" holiday. An excuse to party.

I once read a funny satire suggesting that hundreds of years from now Elvis Presley will be the founding icon of a new world religion. Mojo Nixon did a wonderful song - - Elvis is Everywhere - - I will post a link when I get around to it.

clark · 2004-01-28 11:12:37

Careful with the flashing Bill, there are children present.

Saint Bob, patron saint of the Mars nu.. err, i mean Mars settlers..

Of course it would seem a great many are willing to follow him into the desert, so why not make him a saint. Or better yet, just seal the deal and call him a prophet. [shrug]

Put a little oracle up on Olympus Mons, perhaps have people make long journeys to divine their future from the temple.

:laugh:

Yang Liwei Rocket · 2004-03-09 06:18:10

if only the Incas and Egyptians priets and writers were around, I'm sure they would ahve made a good martian calendar

we need a calendar for the future colonists and workers of mars

bdm · 2005-03-24 20:58:02

I feel evil, being a new user stirring up old threads, but I feel it's better to use existing threads rather than creating new ones that discuss exactly the same material.

There seemed to be a lot of controversy regarding the days of the week and religion. The controversy existed because of the one unspoken assumption that everyone made: that the intercalation of leap years must be performed by inserting one day.

This is not true.

There are calendars in use today that have intercalary periods longer than one day. ISO 8601 specifies a 52-week calendar that intercalates an extra week when the corresponding year has 53 Thursdays. The Hebrew calendar and the Chinese calendar both intercalate entire months.

This is why the Martian calendar I designed has an intercalary week. The idea of intercalating an entire week may seem a little odd, but let's consider how the calendar will be used.

Any Martian calendar must meet diverse needs.

Religious needs have been discussed in depth here already, so I won't need to add my own arguments on that topic. Needless to say, I considered the religious need to meet the Fourth Commandment seriously, so my calendar design has an unbroken cycle of a seven-day week. There are no blank days, and no days missing from the week.

Business needs are also important. One important need that business has is to break up the year into various subdivisions to aid in fiscal management. For ease of use, it would be best if those subdivisions were as even in size as possible. This requirement rules out calendars where the months vary in length to match the seasons. The need to have the equinoxes and solstices begin on the first day of a month is not as great as the business need for efficient fiscal reporting. Therefore, to the maximum extent possible, the months in my calendar design have the same length.

Another business requirement would be for the calendar to have as few variations as possible. The Gregorian calendar has 14 variations, with years of two different lengths beginning on any day of the week. If a diary for a particular year gets printed and remains unsold, it is generally considered useless and is discarded. This wastes resources. Various resources on Mars may be in short supply, or may need to be imported from Earth, so minimising such wastage is important. A perpetual calendar minimises these variations in the layout of the year and thus minimises waste. My calendar design is perpetual, with only 2 year layouts - long years and short years.

Another requirement would be to make the calendar hemisphere-neutral as much as possible. So many designs for Martian calendars make the implicit assumption that everyone living on Mars will live north of the equator that I don't even bother looking at those designs anymore. As soon as someone makes a gross error like that, it's safe to assume that the rest of the calendar will probably contain errors as well. Suppose Mars was terraformed so that it had oceans. If that happened, most of the Martian northern hemisphere will be underwater and most people will live south of the Martian equator! Would they still use northern hemisphere seasonal conventions?

A final requirement would be to make the intercalation rules as easy as possible, both now and in the distant future when the number of days in the year has been reduced due to tidal friction.

My calendar design is a calendar with leap weeks. The year lengths are 665 days (short years) and 672 days (long years). 665 days is exactly 95 weeks, and 672 days is exactly 96 weeks. There are 24 months in the year. All months have 28 days, except the last month in short years which only has 21 days. A year is a long year with 672 days if (Year * 39) mod 76 < 39, otherwise it has 665 days.

The design has many strengths and few weaknesses. The strengths are fairly obvious. The main weaknesses are:
* The use of leap weeks may take some cultural adjustment. In particular, the anniversary problem for events that occur during the last week of long years needs consideration.
* The last month of short years only has 21 days, not 28.
* The date and time of an equinox or solstice will vary by up to 3+1/2 days either side of a mean date.
* The intercalation is not Gregorian, so it may take some getting used to.

I would like the weaknesses of the design to be discussed. Are the weaknesses fatal flaws that make the calendar unusable, or would they be of relatively minor importance that can be lived with?

The calendar design is discussed in more detail here:
http://www.bdm.id.au/calendar/MarsCalen … lendar.htm

Edit 2006-04-07: The page has moved to a new location, so I updated the link. -BDM

bdm · 2005-03-24 21:11:09

Some people have advocated decimal time with 10 hours in a day. This time period is not very practical because there is little need to divide the day into periods of time that are 2+1/2 Earth hours in length.

100 hours in a day is much more practical. One of these hours is equal to about 14+3/4 Earth minutes. Such a period of time would be suitable for such day-to-day needs as doctors' appointments and the like.

Consider the following, alll expressed in these "hours" of 14+3/4 Earth minutes:
* Working day: 32 hours
* Lunch break: 4 hours
* Favourite weekly television show from Earth: 2 hours or 4 hours
* Length of one class period at high school or university: 4 hours
* Appointment at the dentist: 2 to 4 hours
* Appointment at the doctor: 1 hour

Such a period of time cannot possibly meet all timekeeping needs, but as the first subdivision of the Martian day it would have many practical uses as demonstrated above.

RobS · 2005-03-29 15:22:28

Bruce, this is the most intelligent summary of the calendar problem I have seen, and I like your solutions. I have no problem with an intercalary week. Another solution for names would be January 1, January 2, February 1, February 2, etc. There are calendars that do that as well.

-- RobS

Palomar · 2005-03-29 21:44:49

*Speaking of timekeeping, I read this evening that a timepiece (watch, pocketwatch) lying on a shelf runs differently from a timepiece which is carried around/worn. (Actually I've read this before, in http://www.amazon.com/exec/obidos/ASIN/ … -5555959]a book I'm currently re-reading).

Just thought I'd toss that little factoid in here.

--Cindy

bdm · 2005-04-01 20:42:35

Bruce, this is the most intelligent summary of the calendar problem I have seen, and I like your solutions. I have no problem with an intercalary week. Another solution for names would be January 1, January 2, February 1, February 2, etc. There are calendars that do that as well.
-- RobS

I'm glad you like the calendar. I was surprised that nobody had drafted a similar calendar before. To my knowledge, there was no calendar proposal that had leap weeks with the extra week inserted at the end of the year.

I am familiar with KSR's double-Gregorian month names from the Mars trilogy, but I feel that they pose a few usability issues. January 1 looks too much like a date rather than a month name. This will confuse new settlers. Using letters may work better, like January A, January B etc.

I like the idea of naming the months after constellations, as a few designers have already done. If the months are named after constellations, it may encourage the Martian settlers to study science in general and astronomy in particular. Martian settlers will need a good basic grasp of science if they are to thrive, and having a calendar based on science may encourage them to learn the science that they will need.

Another idea for month names is chemical elements, but I would do it differently. If I was to use chemical elements, I would name the months after the chemical elements found in the human body, in decreasing order of abundance. Thus we would start with plentiful elements like oxygen, carbon, hydrogen, nitrogen, calcium, phosphorus (arranged in decreasing order of mass) and end with the trace elements. The only problem with this scheme is that there are more than 24 elements found in the human body.

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#126 2004-01-21 14:37:17

Re: The Martian Calender and Timekeeping

#127 2004-01-21 15:13:38

Re: The Martian Calender and Timekeeping

#128 2004-01-21 17:02:55

Re: The Martian Calender and Timekeeping

#129 2004-01-22 06:24:11

Re: The Martian Calender and Timekeeping

#130 2004-01-22 07:13:06

Re: The Martian Calender and Timekeeping

#131 2004-01-22 07:24:06

Re: The Martian Calender and Timekeeping

#132 2004-01-22 10:05:23

Re: The Martian Calender and Timekeeping

#133 2004-01-22 10:31:11

Re: The Martian Calender and Timekeeping

#134 2004-01-22 10:50:42

Re: The Martian Calender and Timekeeping

#135 2004-01-27 22:03:58

Re: The Martian Calender and Timekeeping

#136 2004-01-27 22:55:45

Re: The Martian Calender and Timekeeping

#137 2004-01-28 10:48:50

Re: The Martian Calender and Timekeeping

#138 2004-01-28 11:03:07

Re: The Martian Calender and Timekeeping

#139 2004-01-28 11:12:37

Re: The Martian Calender and Timekeeping

#140 2004-03-09 06:18:10

Re: The Martian Calender and Timekeeping

#141 2005-03-24 20:58:02

Re: The Martian Calender and Timekeeping

#142 2005-03-24 21:11:09

Re: The Martian Calender and Timekeeping

#143 2005-03-29 15:22:28

Re: The Martian Calender and Timekeeping

#144 2005-03-29 21:44:49

Re: The Martian Calender and Timekeeping

#145 2005-04-01 20:42:35

Re: The Martian Calender and Timekeeping

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