The Tibetan Calendar

The Tibetan Ephemeris, Calendar, and Almanac

The Tibetan system of astronomy and astrology is extremely complex. It takes five years to study and master it at the Astro Division of the Tibetan Medical and Astro Institute in Dharamsala, India. Students learn to calculate everything by hand in the traditional manner, on a wooden board covered with soot upon which one writes with a stylus. There is no complete ephemeris compiled in which to look up figures. One of the main aspects of the training is the mathematics involved in all the calculations.

The Kalachakra system, like those of the Hindu traditions, gives formulas for determining "the five planets and five inclusive calendar features." The five planets are Mercury, Venus, Mars, Jupiter, and Saturn. Their positions, as well as those of the sun, moon, and nodes, are calculated for the Tibetan ephemeris according to a mathematical model, as was also the case in the ancient Greek system. Thus, it is unlike Chinese astronomy, which derived the positions and motion of the heavenly bodies based mostly on observation. Chinese mathematics, when sometimes applied, is primarily algebraic.

The ancient Greeks used mainly geometry, namely different geometric proportions, to determine and describe the motion of the planets. The Hindu systems developed the sine function, and thus employ trigonometric rather than solely geometric methods. The calculations in the Tibetan system, on the other hand, involve neither geometric proportions nor trigonometric functions, but are purely arithmetic.

The making of the calendar and almanac entails the five inclusive calendar features: the lunar weekday, the date of the lunar month, the moon's constellation, the combination period, and the action period. The first two are involved in the mechanism through which the lunar and solar calendars are brought into harmony.

Both the Tibetan and Hindu systems present three types of days. A zodiac day is the time it takes for the sun to progress one out of 360 degrees of the zodiac. A solar day, on the other hand, is from dawn to dawn. A lunar date days, correlated with the phases of the moon, is the period the moon takes to travel one-thirtieth the distance between new moon positions in each successive sign in the zodiac. The starting point of lunar date days is calculated by a mathematical process similar to that used for determining the position of the sun and planets. They are counted in a cycle of seven lunar weekdays named for the days of the week, which are also the names of seven of the planets. To correlate the lunar with the solar calendar, these lunar weekdays must be made to fit in with the solar days. This is complicated.

Firstly, the exact new moon does not occur at precisely the same time of day each month. Thus, the moon can start to travel one of these little distances of one-thirtieth of its cycle at any time of the solar day. The period it takes to travel that one-thirtieth the distance of its cycle is called by the day of the week. Thus, the day of the week may start at different times during the solar day.

Furthermore, it takes the moon a different amount of time to cover each of these little one-thirtieth distances, since its speed varies with its own position and with the position of the sun in the zodiac. Consequently, the amount of a lunar weekday that passes between the dawns of two successive solar days varies, because the length of a lunar weekday is likewise variable.

Dates of the lunar month, which constitute the second inclusive calendar feature, are numbered one to thirty and last from dawn to dawn in the manner of solar days. The problem is to determine which date is to be assigned to each day of the week. The solution is not so obvious, because the lunar weekdays – which are what determine the days of the week since they are called Sunday, Monday, and so on – start at and last for different lengths of time.

The rule is that the day of the week is decided by which lunar weekday is occurring at the dawn of the lunar date. For instance, a lunar weekday, such as Monday, may start in the afternoon of the second date of a month and end in the afternoon of the third. Since at the dawn of the third, which here is taken standardly to be at 5 A. M., the lunar weekday is still Monday, the third will be considered a Monday.

A day of the week can never repeat or be skipped. Directly after a Sunday, a Monday must follow, not a second Sunday or a Tuesday. However, sometimes the dawns of two successive dates occur within the same lunar weekday. For instance, the lunar weekday Monday may begin five minutes before the dawn of the third, and the next day, the Tuesday, may begin five minutes after the dawn of the fourth. This would make both the third and the fourth Mondays! There cannot be two Mondays in a row. One of these dates must be omitted. This is why in the Tibetan calendar certain dates of the month are skipped.

On the other hand, sometimes the beginnings of two lunar weekdays occur before the dawn of the next date. For example, if the lunar weekday Monday begins five minutes after the dawn of the third and ends five minutes before the dawn of the fourth, then,by the first rule, the third should be a Sunday and the fourth a Tuesday, and there would be no Monday. Since it is not possible for it to go from a Sunday to a Tuesday without an intervening Monday, one of these dates will have to be doubled in order for one of them to be the Monday. This is why sometimes there are two eighths or two twenty-fifths in a Tibetan month.

To make the lunar calendar further correspond with the solar, a thirteenth month must occasionally be added to the year in the form of an extra doubled or leap-month. The rules for which dates are to be doubled or omitted, and when an extra month is to be added are different in the various Tibetan astro lineages. This is their major difference. The various Hindu calendars also have doubled and omitted dates, and both they and the classical Chinese calendar have doubled months. The rules followed are not the same as those in any of the Tibetan systems.

The third inclusive calendar feature is the moon's constellation. This does not refer to the moon's actual position at the dawn of a lunar date, as calculated by the five planets' techniques, but rather to its successive associated constellation. For any particular lunar date, this is the constellation position the moon would have at the beginning of the lunar weekday occurring at the dawn of that date, according to which that date was assigned its day of the week.

The fourth and fifth features are the combination and the action periods. There are twenty-seven combination periods. Each is the period during which the combined motion of the sun and moon equals one twenty-seventh of a complete zodiac. For any time, then, we derive the combination period by adding the corrected position of the sun to the moon's successive associated constellation position. Thus, each period starts at a different time. They have specific names and interpretations, with some being less auspicious than others are.

Lastly, there are eleven action periods, derived by dividing the thirty lunar dates in a rather unsymmetrical manner. There is no need to give the details here. Each of the eleven action periods has a specific name and likewise some are less favorable than others are for certain activities.

Special Dates in the Tibetan Calendar

The Tibetan calendar and almanac play a large role in Tibetan life. One of their most important usages is setting the dates for various Buddhist offering ceremonies or tsog. The tenth of both the waxing and waning phases of the moon, in other words the tenth and twenty-fifth of each lunar month, is the day for making ritual offerings to the Buddha-figures Chakrasamvara, sometimes known as Heruka, and Vajrayogini, as well as to Guru Rinpoche Padmasambhava, the founder of the Nyingma tradition. Out of all these tenths, the twenty-fifth date of the eleventh Tibetan month is the most important day for Chakrasamvara, and the tenth of the twelfth Tibetan month for Vajrayogini. The eighth of each Tibetan month is the special day for making offerings to Tara. This is only during the waxing phase of the moon.

If, for instance, a Tibetan month has two tenths, the offering ceremony is made on the first of these. If the tenth is omitted during that month, the ceremony is held on the ninth. This rule is followed for all religious practices to be performed on a specific auspicious date of the Tibetan calendar.

In each Tibetan Buddhist lineage and within each monastery of each tradition, the schedule of the rituals performed during the course of the year is defined in terms of the Tibetan calendar. The summer retreat is normally held from the sixteenth of the sixth Tibetan month until the thirtieth of the seventh month. This is known as the early summer retreat. Gyuto and Gyumay Tantric Monasteries of Lhasa follow the later summer retreat from the sixteenth of the seventh Tibetan month until the thirtieth of the eighth month. Moreover, in the Gelug tradition, the twenty-ninth of each lunar month is the special day for the Buddha figure Vajrabhairava, also known as Yamantaka, especially relied upon for protection from obstacles and interferences. For this reason, meditation retreats for intensive practice are considered best begun on this date of any Tibetan month.

The Buddhist holiday of Vesak celebrates not only Shakyamuni Buddha's parinirvana or passing away, but also his date of birth and enlightenment.Vesak, or sometimes Wosak, derives from the Pali equivalent, used in Theravadin countries, of the Sanskrit month Vaishakha, which is the second Kalachakra and fourth Tibetan month. This holiday is celebrated on the full moon day, i.e. the fifteenth, of that month. Since the Theravadin calendar is different from that of the Tibetans, and derives from one of the Indian Hindu systems, Vesak works out to be one month earlier than in the Tibetan scheme.

Two other events from Shakyamuni Buddha's life are celebrated. After Buddha demonstrated his enlightenment under the bodhi tree in Bodh Gaya, the first person he taught was his mother, who had passed away in his childbirth and was reborn in the Heaven of the Thirty-three Gods or, according to some sources, in Tushita Heaven. Buddha traveled there to teach her. The holiday of the Descent from the Heavenly Realm, celebrated on the fourth date of the sixth Tibetan month, commemorates Buddha's return to this world. Buddha then went to Sarnath and at the Deer Park taught his first human disciples. The holiday of Setting Flow Rounds of Teachings (Turning the Wheel of Dharma), on the twenty-second of the ninth Tibetan month, celebrates this.

Each of the Tibetan Buddhist lineages also has its special days. For instance, in the Gelug tradition the holiday Ganden Fifth Offerings, on the twenty-fifth of the tenth Tibetan month, commemorates the passing away of Tsongkhapa. Monlam, the Great Prayer Festival in Lhasa, takes place from the third to the twentyfourth of the first Tibetan month. On its final day, there is traditionally a Tossing Out of a Ritual Cake ceremony performed by the State Oracle Nechung, during which all obstacles for the new year are symbolically removed. This is followed on the next day, the twenty-fifth of the first month, by the celebration of the Inviting Maitreya Festival, during which an image of Maitreya, the next Buddha, is paraded around Lhasa in an ornate cart.

There are also specific dates for the consultation of oracles. For instance, the Tibetan government traditionally consulted the Nechung State Oracle on the tenth of the first month. In Tibet, the Abbots of Drepung Monastery regularly consulted the Nechung Oracle on the second of each Tibetan month.

Tibetan calendars regularly mark three types of inauspicious dates. "Bad days" are marked with the Tibetan letter zha, and last from dawn to dawn. "Black days" are marked with a nya, and cover only the daytime. Both occur on fixed dates each year, one during each Kalachakra month. The third type of inauspicious date, marked with a ya, lasts both day and night. It is known as "Yen Kuong days," after the name of a Chinese deity. There are usually thirteen each year and they occur on fixed dates of the broad Chinese-style months of the yellow calculation system. Furthermore, from the Chinese-derived element calculation system, each year contains two "black" or inauspicious months, and occasionally there is a "black" year.

The other type of date on the Tibetan calendar marked with a letter, this time sa, is for the bimonthly ceremony of the monks and nuns for the purification and restoration of their vows, the sojong ceremony. Each year, the first of these is held fifteen solar days after the new year. Tibetan months begin with the waxing period of the moon. The second sojong each month, at the end of the waning period, is held fourteen lunar date numbers after the previous ceremony. If there is a doubled date, both those dates are taken as one in the count. If there is an omitted date, an extra date's number must be counted to make fourteen. The first sojong of each month, at the end of the waxing period, is held simply fifteen solar days after the previous ceremony, with no regard to doubled or omitted dates.

It should be noted that, in general, the waxing half of the month is considered more auspicious than the waning. Therefore, most Tibetans will begin constructive, positive practices during the first half of the lunar month so that the results will increase and expand like the waxing moon.

Auspicious and Inauspicious Dates

In addition, certain dates are considered auspicious and others inauspicious for various specific activities. For instance, the ninth, nineteenth, and twenty-ninth dates of a lunar month are auspicious for beginning journeys, whereas the so-called "water-strainer" dates of the second, eighth, fourteenth, twentieth, and twenty-sixth are unfavorable for travel. This is why if Tibetans cannot begin a journey on an auspicious date, they will often take a piece of their luggage and move it a little down the road to another house on the auspicious date, so as to begin the journey symbolically on that day. However, if one dies on the ninth, nineteenth, twenty-ninth, or when the moon is in the ninth constellation, or on a Sunday, and especially on a date when all three occur together, this is considered inauspicious for those left behind.

The most inauspicious date of the year is the "nine bad omens day." It starts on the sixth date of the eleventh Tibetan month at noon, and lasts until noon of the seventh. During this period, most Tibetans do not try to do any special religious or other positive practices, but instead go on picnics, relax, and play. The history of this custom is that at the time of the Buddha, one person tried to accomplish many positive deeds this day, but nine bad things befell him. Buddha advised that on this date each year in the future, it is best not to try to accomplish much good.

The immediately following twenty-four hour period, however, from noon of the seventh date of the eleventh month to noon of the eighth, is the "ten good omens day." On this day, at the time of the Buddha, ten wonderful things happened to that same person when he continued trying to do what was constructive. This period, then, is considered very favorable for positive projects but, in general, Tibetans also take this time for picnics and games.

Two other periods of the year are indicated in the almanac and are noteworthy. The first is called the "dawning of the star Rishi." This is calculated from a certain type of point in the eighth Tibetan month and lasts for seven days. During this period, the light from the star "Rishi" shines on the gem on the crown of a certain fabulous statue, causing nectar to flow from it. This causes hot springs to be most effective and thus these seven days are the so-called bathing days when Tibetans go to hot springs for treatment and cures.

The other is called the "poison pig days." They also last for seven days and are calculated from another type of point in the fifth Tibetan month. During these days, due to the effect of a contaminating rain, waters turn to poison. Any medicinal plants picked on these days will be poisonous. Likewise, hot springs will be very detrimental, and so everyone avoids them.

Although, from the Chinese-derived element calculation system, there are many obstacle periods during our lifetimes, the most major one noted by all Tibetans is the "obstacle year of age." This is each year during which our natal animal-signs recur. Thus, if we were born in a year of the rat, then each subsequent year of the rat would be an obstacle year. This occurs, then, every twelve years. According to the Tibetan way of counting age, where each calendar year in which we are alive is counted as one year of age, then during the first of these, we are one year of age, during the second thirteen, and so on.

Buddhist Approach to Astrology

There are so many variables that can affect the interpretation of any particular period, both in general and for an individual, that almost any time will have something wrong with it. Not all factors have an equal importance. Only certain variables are examined for one situation or another, and some will overrule others. Thus if a journey can be begun on a ninth, nineteenth, or twenty-ninth date, or a Kalachakra empowerment be given on a full moon day, it is not so crucial that other factors might be unfavorable.

The aim of this system is not to cripple people with superstitions. Rather, it provides the populace with something like a weather forecast. If we have a general idea that a certain date might not be so favorable, we can take specific preventive measures of performing ceremonies, acting in a kind, careful manner, and so on, as a way of overcoming or avoiding problems. It is like carrying an umbrella when one hears it might rain.

Buddhism does not view astrology in terms of influences coming from the heavenly bodies as independently existing entities totally unrelated to each individual's mental continuum, but rather as a reflection of the results of our previous impulsive behavior or karma. A horoscope, actually, is almost like a map for being able to read aspects of our karma. One of the comprehensive results of our impulsive actions in previous lives would be the reflection of our karmic situations in the astronomical and astrological configurations into which we are born. Therefore, astro information can give a clue about the results that might come from our previous impulsive actions unless we take preventive measures to alter the situation. Thus, it helps us to know how to handle any predicament. Likewise, an almanac indicates the comprehensive results built up and to be experienced by a large number of individuals together.

There is nothing fatalistic about the Buddhist worldview. The present situation has arisen from causes and conditions. If we can accurately read that situation, we can act in such ways as to create different causes and conditions for improving it even in this lifetime, for the benefit of both ourselves and others. This does not mean by making offerings or sacrifices to the various deities of the heavenly bodies to appease them and avert their harm, but rather by modifying our own attitudes and behavior.

On a popular level, when it is sometimes recommended that in order to extend our lifespans we need to commission a statue or painting of a certain Buddha-figure, it might seem that this is to gain the favor of that figure. This is an uneducated misconception. The attitude generated in such an undertaking is what has the most effect. If it is one of fear or selfishness, the effect will be minimal. Far more effective in prolonging our lives and improving our health and material situations are specific meditation practices when done with the motivation of being able to benefit others.