Adopting a LunarCalendar
Brainstorming a Calendarfor Lunar Settlers
by Peter Kokh, © 2005 The Lunar Reclamation Society This Paper is a Work in Process, and may be added to.
Six prior articles in Moon Miners' Manifesto
"Essays in 'M': Month, Meridian, Metonic Period"
MMM #7 July 1987 (online article) (re-edited text below from MMM Classics #1 pdf)
by Peter Kokh
M FOR MONTH, OR SUNTH:
Originally, of course, the term "month" meant the span of a full set of four phases of the Moon, e.g. from full moon to full moon, or from new moon to new moon, terms which render the appearance of the Moon to the inhabitants of Earth. On the Moon itself, this lunar month of 29.53 Earth days would rather appear to denote a full set of phases of Earth, e.g. full earth to full earth, except that this defini-tion of month would seem irrelevant to anyone living on the Farside from which Earth was never visible.
Rather, to the Lunar Settlers, this period, called a lunation by our astronomers, will simply signify the period from sunrise to sunrise or from sunset to sunset - wherever they happen to live on their adopted new homeworld. From a Lunan's point of view, it's all about where the Sun is in their sky, and has nothing to do with Earth at all. Earth could cease to exist and their would be no more "full moons" or "new moons" to reckon by. Just the interval between sunrises (or sunsets).
Introducing "the Sunth"
Accordingly, pioneers might well prefer to call it simply the "sunth." This term is less stuffy than "lunation" which is really a geocentric term signifying the period from "new moon to new moon." The term "sunth" and avoids confusion with our own Earth calendar months of Roman origin which do not coincide at all with lunar months as they average about a day longer in order to divide the year into twelve neat periods with no leftover days. The Sunth then would be the natural way of reckoning the passage of time on the Moon.
The sunth will also be the primary consideration in scheduling activities which depend upon the availability of sunlight and/or solar power. This will include mining and industrial operations, road building and prospecting, The local time of sunth will also determine the timing of agricultural chores.
M IS FOR MERIDIAN:
The Replogle globes of Earth and Moon alike are divided into 15 degree longitudinal segments. For the Earth, this is a natural, since 15 degrees is the width of the idealized "time zone" (15 x 24 = 360).
On the Moon, however, the slow daily crawl of the terminator line dividing sunshine from darkness is just over 12 degrees (12 deg., 11 min., 27 sec.). So for the purposes of settlers of the Moon or for people on Earth who want to better comprehend what life on the Moon would be like, future Moon globes might display meridians marked every 12 degrees. Thirty 12° sections equals a full circle of 360° Thirty quasi "date zones" if you will. Even if these zones do not precisely measure the sun's slow crawl across the sky they would offer a close enough approximation to allow Lunan students and others to easily estimate by how many dates the sunth is retarded or advanced in his/her location in comparison to other settlement sites and outposts on the Moon.
M IS FOR METONIC PERIOD:
A 5th Century B.C. Athenian by the name of Meton noticed that the Moon's phases returned to the same dates of the year after 19 years ( i.e. 228 calendar months = 235 lunar months ). The Metonic period is important for anyone who would devise a calendar which respected the 29.53 day lunar month or sunth, and yet reconcile it with Earth's 365.25 day year at least periodically. *
A Moon Calendar for Lunar Settlements
MMM #7, July 1987 (online article at www.asi.org/mmm/ )
The text below is from the re-edited version in MMM Classics #1 pdf
by Peter Kokh
To be sure, there will be settlers on the Moon with "Tory" hearts, i.e. unwilling to give up the ways of Old Earth, however inappro-priate to the new world. Earth's calendar is one such piece of baggage best left at home. On Earth, counting time by "moons" may be conven-ient for nomads and rustic hunter-gatherers, but the overriding temporal fact of life since the dawn of the agricultural age remains the length of the year: the four seasons.
But on the Moon, however, the four seasons do not apply -- except for astronomers. The overarching pacer of life will the the sunth (see M is for Month, above).
Keeping the standard 24 hour day/date
Because of Earth's proximity to the Moon and the high density and intensity of Earth-Moon communications and commerce (as compared, for example, to Earth-Mars intercourse), it will be convenient to keep the standard 24 hour day -- probably called "date" on the Moon to avoid confusion with the longer sunth.
Then a two page calendar would always be valid even as to the times of local sunrise and sunset to within the hour, per location.
Advantages of an occasional 8-day week
Such an extra day would be a logical choice for religious feasts and holy days and for secular holidays alike. Since the extra day would not be a working day but an off day providing three long weekends out of every eight, it should be a popular feature and add cultural color to life on the Moon.
Naming the Days of the Week
Since, obviously, such lunar weeks and weekdays would not line up or keep cadence with those of Earth (no need to), new names are in order. The reader may have some suggestions. Let me offer three possibilities, naming the days of the lunar week after:
Fiscal Considerations
For fiscal and accounting convenience - divisibility into "quarters," for example - the calendar should have twelve sunths invariably -- like the Islamic model rather than the Jewish one (which sometimes has thirteen). This would yield a short "year" or "ennium" of 354 dates that would slip seven sunths out of alignment with Earth's calendar after nineteen years (see M is for Metonic Period above.)
The Metonic Period: 19 years & 235 Sunths
So every nineteenth year an extra seven sunth period could be added, to be called "the Renaissance" and devoted to constitutional and institutional renewal, reform, and rededica-tion, thus bringing the Moon's calendar back into step with Earth's and providing a predic-tably popular generation-long rhythm as a crea-tive fringe benefit of which lunar civilization could be proud.
There are alternatives of course, but why compromise with those inappropriately attached to terrestrial customs. It's a brand new world and why not start fresh with new traditions? "Tories" can always import Earth calendars and keep them under their pillows.
[The Lunar Calendar issue will be revisited in later issues of MMM.]
"Dayspan"; "Nightspan"; "Sunth"
MMM # 43 MAR '91, pp 4-6
by Peter Kokh
The DAYSPAN
For the watchers on the ridge, it begins with an arcing flame of light punctuating the still dark eastern horizon -- part of the solar corona, something that the atmosphere-coddled Earthbound can never see, except during locally exceedingly rare 'total' solar eclipses. The Sun's intense disk is now still below the horizon, but this great prominence announces its imminent arrival onto the moonscape.
Here on the Moon, the Sun rises with great deliberation. From 'first contact' when the first diamond glint of light from the solar surface itself breaches the horizon, until 'last contact' when the entire blazing disk has just cleared, the Sun takes sixty ceremonial minutes to make its entrance. For such is the slowness with which the Moon turns on its axis to bring the Sun into view. (On the fast turning Earth, this show is run through in fast forward so that it amounts to no more than a two minute skit.) Two hours later, the Sun will have cleared the horizon by only a degree. It will not reach the far horizon, 180o degrees away, for another 14 3/4 days, better than two weeks.
But already this first standard day of the new sunrise, there is a noticeable shift in settlement activity, and a quickening of its pace. Within a few hours of first light, solar panels and/or solar dishes, and the many sun-tracking, grabbing, and channeling heliostats will have all locked on to its life- and energy-giving rays.
The Sun is both workhorse and taskmaster for the little community. With its return, added electrical power surges online. Solar furnaces melt charges of raw, or refined, regolith for the productions of sundry items from cast basalt, ceramics, glass, and glass-glass composites or Glax™. The concentrated rays are also put to work sintering iron fines scattered abundantly in the loose regolith blanket, and collected with a simple magnet, into assorted useful pieces using powdered metal technology. And either directly through focused heat, or indirectly through electricity, industrial-strength sunshine begins cracking water reserves back into hydrogen and oxygen for use in fuel cells aboard field vehicles and, stockpiled until sunset, for reserve nightspan power generation.
"Make hay while the Sun shines!" Not only does the pace of mining, processing, manufacturing, and field activities such as construction, road building, and prospecting, rise dramatically, but so does that of farming and home sunspace gardening. Plants emerge from their 'subsistence diet' of reduced artificial lighting during the nightspan, thrive anew and resume their progress towards eventual harvest. For most of the base personnel or settler population, the tempo of life has significantly accelerated.
More people venture abroad, "out-vac", either for work or just for a welcome change of scenery, excursion vehicles being the popular choice over cumbersome space suits. "Selenologists", still lazily called 'geologists' by their chauvinist Earth-tied colleagues, venture out of their labs to collect fresh samples in the field.
Habitats and pressurized common spaces (the "middoors") are flooded with soul-warming sunshine, thanks to the heliostats which filter out both the unwanted heat of the infrared and the harmful fury of the ultraviolet rays. Stained glass and prisms turn sunbeams into a painter's palette and interior and middoor surfaces take on a new glory. Walls, finished with a cheap whitewash of CaO lime or TiO titanium oxide suspended in a waterglass medium of hydrous sodium silicate, make an ideal canvas for these rainbow-bright live paintings. Greenery, its verdant hues more vivid after 'breakfast', completes this characteristic settlement color scheme.
Oases of park space tucked into crannies of the various food-raising areas are thronged during free time. School yard recess is imbued with renewed spirit. Those going to and from work along pressurized passageways lined with carefully chosen plantings seem to smile with a subtle new radiance.
Any ship carrying tourists will arrive while the Sun illuminates the area. Perhaps most of the visitors will stay to experience the full rhythm of settlement life, and depart during the following dayspan some three or four weeks later.
Long forgotten is the ho-hum grudging routine of daybreak on Earth, oft' equated with life before coffee. Here the Sun's glorious presence transforms everything through and through. For the fourteen plus 24-hour days of dayspan, the life of most settlers will be one of especially earnest industriousness. In every field of dayspan-reserved activities, there will be important production goals to meet if these brash settlers are to "set themselves up" for the quite different, but complementary, routine to follow.
<<< MMM >>>
The NIGHTSPAN
For the previous two plus weeks, this unlikely pocket of humanity on the Moon has been a beehive of activity, making use of the Sun's heat, its life-giving rays, and its electrical generating potential, to work through the more energy intensive portion of the long list of tasks needed to keep the community going. For total available on-line power will drop measurably as the Sun finally reaches the western horizon.
While the light available on the surface will remain full-strength until the final two minutes, 'down below' the level of redirected sunlight will have begun to taper off the past day or so as heliostats on the surface, even arranged in purposely staggered rows, begin to eclipse one another, cutting off solar access.
Industries dependent on harnessed and concentrated sunlight will have been located to avoid this problem, so they can keep working on full throttle for the full duration of 'sun-up'. Finally, however, the great solar furnaces and turbines will be shut down and the activities they support will stop. Those industries that depend indirectly on abundant electricity generated by solar arrays must likewise phase down. For whether supplied by standby nukes, fuel cells, spinners, or hydroelectric generators (where rille or crater slopes allow the possibility of pumping up water surplus by dayspan to let it fall during the nightspan), the total amount of on-line electrical power will be likely be appreciably reduced for the fortnight to come. Industry after industry will switch gears, taking up now the rather more labor-intensive tasks that it had strategically postponed during dayspan.
Maintenance, repairs, and changeout of equipment; assembly and finishing; packaging for shipment; bookwork and inventory; - for many workers, it will be rather like switching jobs every two weeks. And perhaps that will be a welcome break in the routine, an anticipated and appreciated periodic shot in the arm, an essential element in sustaining personal and communal morale.
Workers who by dayspan crew those industries that do not have a proportionate list of postponable energy-light labor-heavy tasks to keep them busy during nightspan, might shift to quite different company co-owned ventures that are task-lopsided the other way. Unneeded farm workers might move to food-processing duties etcetera. Continuing education, especially in the line of one's work, might be preferentially scheduled for nightspan.
The Sun now set, Lunans, temporary personnel and permanent settlers alike, will find more leisure time for arts and crafts and cottage industry pursuits. Music, dance and other performing arts will vie for attention. Now there may be more time for shopping and flea market barter. Perhaps only necessities will be bought and sold during dayspan when able persons are best occupied building up export inventories to defray import costs, and producing domestic items to reduce import demand.
Fresh new pioneer recruits may have arrived shortly before sundown. This will give them a taste of what dayspan settlement life is like, saving more intensive orientation for the nightspan when extra senior personnel will be freed up from other duties to devote themselves to this task.
The public spaces of the settlement - its middoor squares, streets, alleys and passageways - might be more crowded during nightspan with people free to linger leisurely and enjoy activities for which there was little time the two hustling weeks before. Such places will come alive with entertainers and soap box orators, artists and craftsmen selling their wares or demonstrating their talents and taking in serviceable but prosaic "issue" items for customizing makeover into items of pride, hucksters selling similar items on commission, secondhand stalls and exchanges for recyclable items, shelves of produce harvested from in-home gardens and specialty jars of preserves put up by enterprising home-canners - you get the idea.
Ambiance provided by electric lighting can take several forms. Great electric lamps might use those same sunshine-delivery systems slaved to heliostats during dayspan to provide periods of simulated daylight each nightspan 'day', with subtle mood-setting lighting for nightspan 'nights' (night life and sleep time).
And color? Colored bulbs as well as stained glass diffusers and dividers will be one way to provide a magically cheerful touch. A harvest of neon and other noble gases adsorbed from the Solar Wind to the fines of the Moon's regolith soil blanket, and recovered by heating during the routine soil-moving processes of mining, road building, and construction, could lead to ample and creative use of neon lights. The "Greek Isles" look of the community's middoor and indoor spaces, in which sunlight splashes whitewashed walls accented with luxuriant greenery, will be upstaged now by quite a different enchantment after dark. It seems unlikely that our future Lunans will fear the night!
At last, the end of the long nightspan will draw near, and the final evening meal of nightspan may become a special one in settler homes, filled with anticipation, maybe even ceremony: "Sunrise Eve"!
<<< MMM >>>
Will Lunans mark the days by the Month or by the "SUNTH"?
It should be clear from the above pieces that the arrival of sunrise and, a fortnight later, of sunset will radically determine the scheduling of almost every activity within a lunar community beyond eating and sleeping and making love. Given that most Lunan industries and enterprises must stop to shift gears at both sunrise and sunset, it will be of no small benefit to their efficient operation to schedule "weekend" breaks so that they always fall at the same time in relation to these all-transfiguring events. As the Lunar settlement will be "under the gun" to produce enough exports to balance the cost of needed imports, as well as enough domestic goods to minimize that import need, achieving such smooth operation is not a goal to be dismissed .
But here's the rub. Sunsets repeat every 29.5 days (twice every 59 days) or 12 times a year with 11 plus days left over. The Jews and Moslems have such a calendar of "lunar months" (a tautology, when you think of it). But the Romans, while inappropriately keeping the word, altered the "month" so that an even dozen fit in each solar year. For us on Earth, where the really significant repeaters, affecting business cycles as well as agriculture, are the seasons whose onset is determined by our annual orbit around the Sun, quite irrespective of the lunar phase of the moment, the solar "month" (how that grates!) makes sense.
If the word "month" is no longer 'honest' for our calendrical tomes of 28-31 days, neither does it fit the sunrise to sunrise period on the Moon itself. From the viewpoint of one on the Moon, it is the Sun's aspect which is significant. Hence our suggestion [MMM #7 JUL 87, p9 "Calendar"] that the term "sunth" be coined for the purpose. Astronomers use the term lunation, but as this properly refers to the new moon to new moon period (that is, reckoned from local sunrise at 90o East), it is not sufficiently generic, and again inappropriately refers to the Moon, not the Sun (we would accept Lunar Solation).
Back to our question. Will future Lunans mark the days by Earth's months or by the local sunth? Perhaps they will use both calendars side by side, or a special calendar with dual dating. To visitors from Earth, as to those serving temporary tours of duty with no intention of staying for the rest of their lives, the Earth date will be the "real" date, as if our arbitrary notation were some cosmic fact. Even "Tory" settlers (those who have made the move in body but not in spirit) will feel reassured by a glance at our familiar Gregorian calendar.
Meanwhile, not only will settlement life totally ignore terrestrial conventions out of practical need, but both exports and imports and the arrival and departure of tourists will pay heed to the local Sun angle (the time of sunth) rather than to the date on Earth. Business and accounting cycles for Lunan entrepreneurs will follow the march of sunths, not months. Even those businesses on Earth trading with the Moon will need to refer to the lunar calendar (or at the lunar phases shown on most 'normal' calendars) to help determine shipping times.
From the 59 date sunth-pair to a full "lunar" calendar is a big step, however. For adopting a twelve sunth year of 354 days would put Lunans out of synch with Earth. IF they decide that this is not important, they have three basic options. A) they can simply let their 'years' (or 'calendars') advance over Earth years without any attempt to make an adjustment, as does Islam, giving it 33 years to our 32, or B) they can add an intercalary thirteenth sunth every second or third years, as does Judaism, or C) let the differences accumulate and add 7 extra sunths at the end of every 19th year (conveniently, there are precisely 235 new moons every 228 calendar months). If this last option seems far out, it does present a neat opportunity for a once-a-generation built-in period for institutional and cultural review. Those extra seven sunths could be collectively be called "renaissance" or "renewal".
IF keeping in sync with the year as reckoned on Earth is to be desired, sunths could be numbered 1 to 235, rather than named, in a cycle repeated every 19 years, while the year began and ended in lock step with the familiar Earthside cadence.
However the solar year/sunth incongruity is handled, using the sunth to mark the timing of events and activities within the lunar settlement will mean abandoning synchronization with the Sunday through Saturday rhythm so ingrained in us that we assume the day of the week must be a primeval cosmic framework valid in the most distant corner of the universe, even predating it, as some fundamentalists would insist. In fact, not only is the length of the day a purely Earth-local matter of no cosmic significance whatsoever, but the pegging of names to days in a certain suite with a once and for all calibration, is, however traditional, 100% arbitrary. Nonetheless the week, as it has been handed down to us, is the most stubbornly ingrained piece of our "cultural infrastructure", and it has survived all attempts to tamper with it.
Making the switch to sunthtime, if pursued in earnest, will mean pegging 'weekends' to this beat, i.e. an integral 4 weeks per sunth, i.e. no leftover days, with each sunth starting the same day of the week. But in every 59 day sunth-pair their are 3 days more than an even 8 weeks. An adjustment can only be made by making 3 weeks out of every 8, 8 days long instead of 7. If each of these extra days was placed to make a long weekend, and used for all holiday observances, this would provide 18 holidays a year, quite in line with American practice, but in a non-disruptive format. A "leap hour" every six or seven 'weeks' would keep the 59 day rhythm from drifting, as the sunth is some 44 minutes longer than 29 and a half days.
To avoid confusion (Monday on the Moon while it is Wednesday on Earth, at least this week etc.) Lunans will most likely adopt a totally new set of 7(8) names. The previous MMM article alluded to above, has some creative suggestions for the pioneers.
Another major question to be settled is whether all Lunan communities will observe the same weekend schedule, no matter how many 12o-wide 'date-zones' they lie apart from one another, or whether local weekends will fall with local sunrise and sunset. There are strong tradeoffs and they must weigh and choose.
Such a culturally radical switch in time-keeping would neither be to the point on Earth, nor stand as much chance as a snowball in a supernova. However, Lunans will be living in a workaday environment quite unlike anything ever experienced by any Earth bound community to date. For many settlers, the need to declare cultural as well as economic independence from Earth may be strong. In some form or another, Lunans will adopt conventions of time reckoning that pay only loose homage to our week and month. The year will survive, however, not because the Moon shares the Earth's orbital motion around the Sun, but because the two worlds lie in each other's backyard, assuring a high volume of trade and real time communication*.
I think it will be culturally refreshing! - MMM
<MMM>
APPENDIX
Pioneer Holidays
MMM #92 February, 1996 (online article)
by Peter Kokh
While "new traditions" (as oxymoronic as it sounds) are being made all the time, there is little doubt that those that command our observance most deeply are those which are oldest, rooted in our collective gitgo times. So it is with Holidays: Christmas, Easter, New Years go back millennia (two at least). Thanksgiving goes back nearly four centuries. The 4th of July will be 220 years old next time around.
We can expect that as the lunar frontier becomes fully established with the coming of age of the first native born generation of Lunans, the holidays and festivals they will most cherish will include those observed by those establishing the first beachhead.
The Apollo 11 landing (July 20th) is sure to be observed, as is the "infamous" day of retreat, the liftoff of the Apollo 17 crew (December 10th). But neither of these "trivia" dates will rival the enthused celebration of the "Day of the Return" when humans come back to the moon intent on setting up an open-ended "permanent" presence leading to genuine settlement.
The first crew may only set up camp and then return to Earth, to be followed by the first crew intent on staying a full day-night cycle (the lunar "sunth") or more. So closely connected with the observance of the Day of the Return will be the celebration of that first successful "overnighting" and the greeting of that first "sunrise" -- "First Night's End."
Finally, "Ever Since Day" will mark commencement of uninterrupted human presence on the moon. If I were to put a friendly wager on which of these will be the most honored in Lunan settlement tradition, it would be on "First Night's End." There will be a special flavor to this holiday, the shared mutual congratulations at having survived this "initiation" imposed by the moon itself. And for all non-native born Lunans, there will be a special personal resonance with memories of their very own "First Night" and "First Night's End."
Other history-rooted anniversaries may mark the birth of the first native born Lunan. And later, the first native born grandchild (i.e., second generation, whose health will be the final test of whether or not humans can stay on the moon indefinitely) [See MMM #47 JUL '91, p.5 "Native Born"]
Not all Lunan Holidays and festivities will take root in such historic occurrences. Some are sure to be bound up with the Moon's natural rhythms, much as a growing minority of us terrestrials observe the equinoxes and solstices. Local sunset and local sunrise will be big deals, something to mark with a special meal or wine or friends -- simply because they occur on a 28+ day cycle, not a 24 hour one.
If a particularly appropriate Lunan Calendar is adopted [see MMM #7 JUL '87, "Moon Calendar"], with "sunths" of 28.5 (24 hr.) days instead of 30.5 day calendar months, with the discrepancy with Earth reckoning made up with occasional "leap" ("intercalary") "sunths" or weeks, Lunar New Years may only approximate the fall of New Years on Earth.
In such a case, the observance of religious feasts and holy days may also vary with that on Earth, without spiritual harm to those who honor them. This will be much to the chagrin and resistance of religious fundamentalists (those who give major importance to the minor, and minor importance to what really matters, and call every one else heretic and infidel.)
Solar Eclipses on the moon are the flip side of Lunar Eclipses on Earth. They will be much more of an experience for Lunan pioneers and settlers than any eclipse on Earth (even total Solar). They will last several hours locally, and possibly may occasion the morning or afternoon "off" (work or school) as the case may be. And it will be the most favorable time for looking for city lights on Earth's nighttime face.
In time, other "political" milestones will come to be honored in settlement tradition -- the day when home rule is won, or independence declared, for example.
Historic and festive holidays will not be the only early-rooted traditions. Pioneering songs and ballads, even candidate settlement anthems, are sure to be written, sung, performed, and loved.
There may arise too special festive foods with historic significance. We have pretzels and crossover buns associated with Lent, unleavened bread associated with Passover. Eggnog, Christmas cookies, Easter Eggs, and Pumpkin Pie are among many foods especially popular at specific festive times. On the moon, many long-loved foods and recipe delights will not be available early on. Special early frontier substitute food and menu items, beverages too, even if in time the need to make such substitutions eases, may be prepared and consumed with relish on commemorative occasions. Associated with such holiday tradition meals may be time-revered toasts, blessings, and mutual greetings.
Certain plants are associated with various observances on Earth; poinsettias and mistletoe with Christmas, for example. And plants grown successfully in the early outpost days may come to be associated with various Lunan observances in like fashion.
The first humans to return to the moon may think that all they are doing is erecting, deploying, setting up, demonstrating, testing, etc. But even the little incidental things they do may in time take on special meaning and color not at all obvious at first, to become ritually repeated. This will all occur sometimes spontaneously, other times with alertness, if not deliberateness, as a part of fulfilling the very human need to impose on nature's own rhythms, a festive and commemorative cultural rhythm of our own. Such cultural rhythms are a major element of the social glue that binds generations together. In this way they will bind future Lunan generations, much as similar traditions have always served in terrestrial communities throughout the globe, and throughout historic and prehistoric times.
<MMM>
The Moon Calendar Revisited
MMM #95, May 1996 (article online)
How Lunans will mark the days
by Peter Kokh
Relevant Readings from Back Issues of MMM
In our attempt to uncover the early roots of a distinc-tively Lunan culture, we have looked at the Moon's "sixth-weight" gravity, its airlessness and exposure to the cosmic elements, the natural quarantine it imposes between scattered settlements, its dehydrated state, and its mixed bag of mineral assets. All of these will radically affect the development of Lunan civilization and culture from day one.
But there is yet another brute physical fact about the Moon that will affect everything just as deeply: the slow lethargic crawl of the Sun across the sky - the Moon's 14.75 day long "dayspans" and "nightspans", its 29.5 day "sunth".
[Astronomers call the period from full (or new) moon to full (or new ) moon a "lunation". From a lunar point of view, what is important is the sunrise to sunrise period. It would be silly for them to call it a "month". An "Earth" (full to full or new to new) would make sense only to Nearsiders. So we suggest the "sunth" as the logical term.]
While within habitats and biospheres lighting can be artificially controlled to reproduce the Earth-normal 24 hour lighting cycle, much of lunar industry will have to match the rhythm of its operations to that of the sunth. For even if we have nuclear power to sustain a higher level of nightspan industrial activity, the availability of abundant free solar power during dayspan, will mean that there will always be a premium on getting done as much energy-intensive work as possible during sun-up, preferentially leaving energy-light, labor-inten-sive tasks for nightspan - where possible. This mode of opera-tions will create a strong fortnightly rhythm in many sectors of Lunan life. [see "Dayspan", Nightspan" ref. above.]
Pioneers will be free to use Earth's calendar, its days, dates, and months to govern their lives. Certainly Lunan astronomers and businessmen involved in export-import trade may need to do so. Those addicted to regular TV programs relayed live from Earth, and new settlers not yet committed to a lifetime stay may do the same. But for most Lunans, Earth's rhythms will be totally irrelevant. "The" thing that will matter above all is the timing of local sunrise and local sunset.
One way to harmonize the rhythms of their lives to those of the Moon would be to start with an all new Calendar, designed from scratch to better serve their purposes. If Lunans adopt a system of alternating 29 and 30 (24 hour) date sunths in which each sunth always begins on the same day of the week, then at each location on the Moon, sunrise and sunset would always fall on the same dates of the sunth. This would favor smooth production scheduling and a rhythm to count on.
The only way to do this, however, would be to insert an 8th day, 3 weeks out of eight, yielding 4 weeks exactly each sunth, alternately 29 and 30 dates long. There is a catch. This immediately uncouples Lunar weekday names from those in use on Earth. The eighth day could be inserted in a weekend, allowing for convenient holiday and festivity scheduling with no interruption to the work week, and should be a popular feature. But it is something sure to scare the pajamas off the various warring clans of Friday, Saturday, and Sunday funda-mentalists, all of whom seem to think Earth's weekday sequence is an immutable, transcendental, cosmic law. Indeed, in the past, no proposal for calendar reform has been more certain to fail than a change in the Sunday-Saturday sequence.
For the sake of argument, let us assume that our pioneers are of the mind that this is a brand new world, and fresh beginnings are in order. They opt for the 24 hour date, the 7-8 day week, and the 4 week Sunth. The first of each calendar sunth would coincide with the "Full Earth" as seen from lunar Nearside (this occurs simultaneously with the "new moon" as seen from Earth). Nearsiders will have sunrise in the first half of the sunth, sunset in the second. Farsiders will have sunrise in the second half of the sunth, sunset in the first.
[A detail: because the sunth is 29.5306 days long, not 29.5 exactly, every 40th date, or on the closest weekend thereto, an extra hour would be added (as we do in the fall, switching back from daylight savings to standard time). This measure would keep the 29-30-29-30 pattern accurate - at the price of Earth dates lapping lunar dates by one every 2 1/2 years.]
Next, they will need new names for the days of the week, since their matchup with Earth's weekdays will always be ratcheting backwards with every 8th day insertion, 3 times every two sunths. Using the old names would mean utter confusion. Here are three name set suggestions:
Luna | Io | Europa | Ganymede |Callisto | Titan | Triton | (Titania)
(2) the names of the 7(8) stars in the Big Dipper:
Dubhe | Merak | Phad | Megrez | Alioth | Mizar | Alkaid | (Alcor)
The problem with this suggestion is that the Big Dipper is not visible below latitude 30û south on the Moon and some southern settlements would thus find these names elitist.
(3) the names of the 7(8) stars of the Pleiades star cluster (and the attendants of Artemis, a Greek mythological moon goddess):
Alcyone | Celaeno | Electra | Maia | Merope | Sterope | Taygeta | (Pleione and/or Atlas, the parents of the seven sisters).
Pleione could be used for the 8th day inserted in the mid-sunth weekend, Atlas for the 8th day inserted in every other sunth-end weekend. The Pleiades can be seen from all locations on the Moon as they cross the sky above the lunar equator. The 7-8 date week, again to avoid confusion with the invariable 7 day period of Earth, could be called the Pleiad.
[This Pleiades option is the one this writer personally prefers]
Time Zones?
On the Moon, the Sun rises an hour earlier every 9.5 miles you travel to the east, and that's at the equator, in a shorter distance closer to the poles. There is a 24 hour differ-ence every 12.2û or every 230 miles along the equator. It will be much simpler for all the Moon to have just one time zone.
The fun has just begun. The Sunth-Pleiad solution is the easy part. Those of you figuring ahead must have realized that 12 sunths = 354+ days, 11 less than an Earth standard year.
This has always been the problem with counting by moons, instead of idealized 30-31 day calendar months. On Earth, while the period between full moons or new moons is a handy yardstick, the one thing that really matters above all is the succession of seasons in a 365 day cadence. It is the Solar year, not the lunar year that is king. Two cultural traditions, Jewish and Islamic, have adopted lunar calendars nonetheless.
The Jewish calendar attempts to keep step with the solar year by adding a thirteenth intercalary month, seven years out of nineteen. [There are 235 lunar months exactly in 19 calendar years of 228 calendar months. This is called the Metonic Period.] The Moslems make no attempt to keep pace and end up counting 33 of their years to every 32 of ours (the time it takes the faster 354 day year to lap the slower 365 day).
On the Moon, Earth's seasons by which weather governs agriculture, are of no real concern. Lunar agriculture, in controlled biospheres, can set its own seasons, and will be more sensitive to the availability of free sunlight on a sunthly schedule of two weeks on, two weeks off. Nonetheless, there will be incentives to keep the lunar sunth year and terrestrial solar years in step, at least over the long haul. The Moon, unlike Mars, is in Earth's backyard, and the sheer volume of live communications, and the heavy regular traffic in exports and imports make Earth's dominant calendar something not to ignore lightly.
This said, are there any solutions better than the two mentioned above? The problem with the Jewish solution of twelve 354 day years of 12 lunar months interspersed with seven 383-4 day years of 13 lunar months is that the years are very unequal, a severe handicap for fiscal accounting and economic management. The Islamic solution is to ignore the problem and not make any attempt at concordance.
Option A
One possible but radical synthesis is a Metonic Period sequence of 19 years of 12 lunar months (sunths) of 354 days each, followed by a once-a-generation cultural, social, and institutional renaissance period of 7 "catch up" lunar months (sunths), at the end of which, the lunar and Earth calendars would again be in step. This would provide equal years for accounting purposes, and the cultural, social, artistic, institutional renewal once a generation would be planned, anticipated, and provide a culturally treasured shot-in-the-arm. There are problems with this: how do you count anniversaries, especially for events taking place in the 7 renaissance sunths?
Option B
Perhaps an even more radical solution is to decouple the sunth-sequence from the year. We already have a calendar in which the weekdays are decoupled from the days of the month. That is, January 1st can fall on any day of the week. Months begin in midweek (Mon. thru Sat.) six times out of seven. We could have a sequence of 235 sunths (repeating every 19 years) and allow the Calendar Year or New Years Day to float through the sunths, much as we allow the "First" to float through the week. The sunths could simply be numbered 1 through 235 instead of named. Or, easier to sell, there could be a sequence of 12 names with a thirteenth intercalary sunth 7 years out of 19, Jewish style. A floating New Years Day would keep the terrestrial year counting cadence, while still coupling lunar life to the dayspan-nightspan pace of the sunth.
One could hardly fault Jews for suggesting the wholesale adoption of their lunar calendar complete with the names they have used for the lunar months for thousands of years. For a probably pluralist lunar society, this may not be a diplomatic solution. New neutral sunth names may be in order. Might we suggest something simple: (u in sun is unaccented)
Firstsun would begin with the last (if there are two) new moon (full Earth) in December. In case of two new moons (full Earths), the first would mark the beginning of Leapsun. In either case New years Day, January 1st on Earth, would fall somewhere between Firstsun 1 and Firstsun 29 on the Moon.
Option C
Yet another possible solution would be to have 12 sunths plus 11 extra year end reset days so that all sunths of any given year would have the having the same date/day sunrise-sunset pattern, which would be different from year to year in a pattern cycle that repeats every 19 years (the Metonic Period again). This solution would allow a set conversion to terrestrial dates and allow easy tracking of anniversaries. Because each of the 19 years of the sequence would have a characteristic pattern, they might be named, much as in the totemic Chinese system (year of the dog, of the pig, etc.).
There are two additional benefit of this system: the introduction of variety (the same variety we experience by important dates falling on different days of the week, year after year); and "fairness", if you will. By options A and B, some settlements would always experience sunrise and sunset on their weekends, (some on 3 day weekends!) others somewhere during the week. As industrial operations have to shift gear at these two times, the timing will come with different incon-veniences during weekends than during the week.
The Lunan settlers themselves must consider the merits of the various proposals above and choose one, or come up with something different. Please feel free to "vote" for the solution you like best, or to propose another.
Whatever calendar arrangement settlers eventually choose, it is sure to reverberate throughout Lunan culture, adding yet another layer of distinctive and characteristic differ-ence from the variegated "family" of cultures on Earth.
Physical Calendars
Lunar calendars need to be "perpetual" or recyclable. Options A and B allow a simple two sunth calendar (the 29, 30 date rotation) to be used indefinitely. A movable accent bar over a list of sunths on the side or above would be all that was needed to make it complete. If the day / date squares were reversible tiles, one side the photo-negative of the other, then each calendar could be customized easily to the local sunrise / sunset (dayspan / nightspan) pattern. Materials available are glass, ceramic, and metal. Recyclable organic art du jour could take the place of the "scene of the month" on our own paper calendars. It will be interesting. *
Embracing the Moon's Rhythms: Adopting a Moon Calendar
MMM #150, November 2001 (printed in MMM #150 pdf)
by Peter Kokh
Living and working by the "Sunth"
The slow two-week long crawl of the Sun across the black lunar skies would surely seem to merit the term "alien" along with the equally interminable wait for the Sun to rise again. Meanwhile, in all our activities, we will be in constant scrutinizing communications with Earth. At the beginning, the clock and calendar of our sponsor nation(s) will govern all activity schedules. Not so!
Many activities from field work to mining to energy production will necessarily be timed to the rhythm of local sunrise and sunset -- to the "sunth." Now surely personnel on the Moon can observe such schedule constraints while continuing to use Earth's international calendar for all other purposes.
But as temporary personnel on limited tours of duty are gradually phased out to be replaced by a growing number of volunteers willing to stay much longer, even indefinitely, the sense of adopting a truly lunar calendar will begin to become appealing. Most people prefer a predictable routine over the long term, however welcome occasional breaks may be. The plain fact is that the pace of the Sun, and whether or not it is currently dayspan or nightspan, will greatly affect the agenda for the (calendar) day for most everyone, in most every occupation. If we had a calendar which enshrined this natural lunar rhythm cycle, it would regularize everything.
Reconciling the 24 hour day with the 708 hour long sunth will be the easy part. Lunans would simply alternate sunths of 29 and 30 days, adding a leap hour every 7 weeks or so for a longer night's sleep -- never a shorter one! Of course, that would mean a gradual drift off of whatever terrestrial time zone they had started with -- Houston's Central Time or London's Greenwich Mean Time (Universal Time, Zulu time.) That way they would just be "democratic," sharing clock time with one time zone after another.
The benefit of this observance of sunth time would be considerable. Local sunrise and sunset would occur on the same dates every sunth, give or take a half day depending on whether it is a 29-day or 30-day sunth. This means that work scheduling that depends entirely on the local day/night situation can be regularized from sunth to sunth. Life would take on a certain predictable rhythm. And most people do strongly prefer predictable rhythms.
Factoring in the "week"
One could go further if -- (shrieks of horror from Jewish, Christian and Islamic fundamentalists) settlers adopted a variable length week. Five 7-day weeks with three interspersed 8-day weeks makes 59 days or two calendar sunths exactly. That would put local sunrise and sunset regularly not only on the same date, but also on the same day of the week.
Would people accept this? Historically, the seven-day week has been the single most change-resistant timekeeping interval. But there are ways to compromise. The seven named days could remain, with the occasional intercalary eighth day occurring on the weekend, say between "Saturday" and "Sunday." There would be little resistance to nineteen 3-day weekends a year -- three 3-day weekends every two sunths! -- except by the business sector, of course. The extra day could even be adopted by religious leaders for scheduling seasonal feasts and other religious observances. This presumes some good will on the part of religious leaders and some willingness to adapt their schedule of religious feasts to the lunar calendar. Freedom means that some will simply govern everything by Earth calendars. So be it.
The Weekend
On Earth, many businesses must operate around-the-clock day in, day out -- "24/7." That means that work schedules are staggered or even put on a rotation of 6 or 8 days ("not 7") so that everyone takes his or her turn working weekends. On the Moon it will be even more important to keep expensive capital equipment and expensive shared facilities such as schools and parks open and running all the time. So what is a true "weekend" for the largest number will surely not be so for all. How the settlers decide to "be fair" or "flexible" will be up to them.
The Weekdays
Now I put "Saturday" and "Sunday" in quotation marks for a reason. You see, the sticking point will be that in a system with periodic eight-day weeks, the named day of the week on the Moon cannot long remain the same as the universally named day of the week on Earth. With the very first 8-day week, the next lunar "Sunday" would fall on the next terrestrial Monday. In a little over two months, the days of the week would coincide again -- temporarily. There can be only one way to avoid confusion: adopt a totally new set of names for the lunar days of the week, seven constant and one periodic.
Now there is nothing very religious about the names of the days of the week in most modern languages. The days are named after the seven celestial bodies known to the ancients: Sun, Moon, Mars (Tiw), Mercury (Woden), Jupiter (Thor), Venus (Fria), and Saturn (in English using the Scandinavian equivalents given in parentheses.) So there should be nothing either sacrilegious or antireligious about adopting a totally new set, to avoid any confusion.
Fundamentalists, of course, believe that when it is Sunday on Earth it must be Sunday everywhere in the Universe. In fact it can be Sunday one side of our International Date Line and either Saturday or Monday on the other side, and no one looses sleep over that. Avoiding confusion with Earth's calendar will be essential, just as is avoiding confusion between Metric and English units of measurement. Some suggestions for day name sets of 7(8) names are given in the MMM #7 article cited below.
Sunths and Years do not neatly mix
So far so good. The real sticker comes if we attempt to assign a year number in a lunar calendar. One Earth year, and the Moon does share this once-around-the-Sun pacing, works out to twelve lunar months (sunths from a Lunan's perspective) of 354 days plus eleven and a fraction days left over. That's quite inconvenient, it would seem. In the Hebrew calendar, an adjustment is made by inserting a thirteenth month from time to time. In the Islamic calendar, there is no attempt to keep pace with the solar year count -- the year is counted as 354 days and so shifts constantly with respect to the seasons.
The Metonic Cycle to the rescue
However, there will only be a problem if the Lunans adopt an annually rotating set of sunth names. Happily, there is a way to avoid this. Just by chance, the lineup of sunth and month repeats every nineteen years in a pattern known as the Metonic cycle. In short, 235 "sunths" is very nearly 228 calendar months (a total deviation of only 2 hours!). Now if the Lunans simply numbered the sunths from 1-235 they could still observe the shared terrestrial year count.
There really is no other "elegant mathematical" solution. We've tried to brainstorm the problem in various directions for the past 15 years. Such a solution has been sought in vain by lunar calendar partisans for millennia.
Numbering the sunths from 1-235 with a repeat every nineteen years will work just fine. We could assign them short, easy to remember compound names, using the first syllable roots of the Latin names for the numbers 0-9: ni, un, du, tri, qua, qui, si, sep, oc, nov -- or some euphonic variation thereof.
Starting Points
So where or when would we start counting? The answer is simple, on any nineteenth year in which our January first happened to coincide with a "new moon" or "full moon" -- whichever standard we wanted to adopt. When we see a full Moon, observers on the Moon would see a new Earth (the night hemisphere of Earth would face the Moon.) When the Moon is "new," the side facing Earth is totally dark and observers on the Moon would see a full Earth.
What would be the logical place to start a sunth from a lunar viewpoint? That depends on the chauvinism that comes with where on the Moon you happen to have settled. For Farsiders, any consideration of the "phase" of Earth would be moot -- Earth will never be above their horizons. Perhaps most settlers will live on Nearside where most of the mare plains are located.
Sunrise on the eastern limb (Mare Smythii - Mare Marginis - Mare Australe) at 90 °E would seem as good a starting point as any. That would coincide with "new moon" on Earth. If you wanted to mark the sunth from sunset at that point, the start of the sunth would coincide with what we experience as Full Moon. The settlers must make the decision, and pick up the sunth count reckoned back to the last new Moon or full Moon (whichever standard they pick) that occurred on a January 1st.
To follow or avoid Jewish or Islamic Practice?
Now in both lunar calendars in wide usage on Earth, the Jewish and the Muslim, the start of the month is reckoned from the first observable crescent moon, i.e. a couple of days after the new moon. The settlers can opt either to go with that precedent or break with it (by using the lunar standard suggested above) to avoid any confusion or appearance of religious considerations.
However, if they want a lunar calendar that is ready to go, has a fixed tradition of calculation, and still tries to keep apace with the year count, they could simply adopt the Jewish Calendar with or without its month names, and with or without its feasts and festivals. The one advantage of such a choice would be that calculators to translate Jewish and Gregorian dates into one another already exist, both on paper, and online. But similar calculators could easily be devised for any calendar setup the settlers choose to adopt. It's only a software matter.
Calendars on the Wall
In plain practice, physical Lunan calendars would give the equivalent standard Earth date and day of the week (and/or day count #s 1-365) in fine print alongside the lunar sunth day number and day of the week name. It's simply a layout problem, with a number of good solutions. One great advantage of the Sunth Calendar is that it won't change every year. Lunar Calendars can be made of durable materials.
<MMM>
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