by Shyamasundara Dasa and Markandeya Rishi Dasa
The Bhaktivedanta Book Trust International, Inc.
copyright (c) 1983-1999. All rights reserved.
1. Where to obtain VCAL
2. VCAL is freeware
3. List of files
5. Introduction to the program
6. How to use the program
7. Some basic Vedic astronomy
a. The movements of the moon and sun
b. The definitions of solar and lunar months
i. The solar month
ii. The lunar month and
8. The Pancanga, or the Vedic calendar
9. Reasons to follow a lunar calendar
10. Traditional and modern methods of calculation
11. Some comments on interpreting the Vaisnava calendar
a. Names of years and months
b. When to observe Ekadasi
c. "Break fast 05:18 - 09:34" and "Daylight-savings
d. Double or no tithi
f. Names for the signs of the zodiac
12. Parting Words
Where to obtain VCAL
most recent version of VCAL should be available on the Worldwide
VCAL is freeware
Bhaktivedanta Book Trust International owns the program, but
you are welcome to use it and share it with others. There
are only a few rules. They appear in the file LICENSE.TXT.
List of files
following files are included in this archive:
Overlay used by the main program
Overlay used by the main program
Overlay used by the main program
File containing list of towns
The document you are now reading
Describing changes in each new version.
Questions and Answers for the release of this version.
Your license for the free use of this program
About the festivals mentioned in the calendar
About the saints and incarnations mentioned in the calendar
About His Divine Grace A.C. Bhaktivedanta Swami Prabhupada
About the Bhaktivedanta Book Trust
Brief identification of this program
are welcome to share VCAL with others, but please distribute
the complete archive, not just selected files.
spell Sanskrit (and Bengali) names and terms, VCAL uses "as-if-diacritical"
spellings. That is, it spells as if it were employing the
diacritical marks used by scholars, but leaves those marks
out. Thus "Krishna" is spelled "Krsna." The VCAL documentation
follows the same system. A guide to the Sanskrit transliteration
system is found in all the books of the Bhaktivedanta Book
Introduction to the program
calculates Vedic lunar calendars. There are different ways
to make calendars according to the Vedic lunar system, all
very similar. This program makes the calendar according to
the Gaudiya Vaisnava tradition, an important branch of the
Vaisnava tradition. The word "Vaisnava" denotes a worshiper
has been developed for ISKCON, the International Society for
Krishna Consciousness, which follows the Gaudiya Vaisnava
tradition. But the calendars VCAL produces should be useful
for most people who follow a Vedic lunar calendar.
was written by Syamasundara Dasa. He and Markandeya Rsi Dasa
developed it further.
develop the program, in June 1989 Markandeya went to India
for extensive research and consultation with persons knowledgeable
about calendar making, astronomy, and Vaisnava observances.
The learning and expertise of those consulted have contributed
greatly to the reliability of this program.
How to use the program
runs under DOS. It is not a Windows program. To install it,
simply place all its files in any directory. To uninstall
it, simply erase the files.
program is easy to use, with a simple menu system. The F1
key gives you context-sensitive help.
uses a list of towns for which it can calculate a calendar.
You may enter new towns as needed, to a limit of 1200. If
you need more, you must delete some towns you don't use. (Or
you can keep more than one town file and switch between your
files by renaming them.)
greater than 65 degrees and 35 minutes (north or south) cause
problems for VCAL. Using such latitudes may result in wrong
calculations or may terminate the program with an error.
you add new towns to the list, take care to enter the latitude,
longitude and time zone correctly. If any of this information
is wrong, your calendar will be incorrect. (If you give your
modified town files to others, this warning is even more important.)
also provides for "batch files," which allow you to calculate
several calendars at a time. When you choose, from the Main
Menu, "Make Vaisnava Calendar," you will be asked, two screens
later, whether you want to calculate the calendar for only
one town or for many. If you choose "many," VCAL will present
you a list of the available batch files. Each batch file allows
you to calculate calendars for many towns through one command.
can also use VCAL to calculate birthdays. Insert the birth
information according to the Western calendar, and VCAL will
tell you the corresponding Vedic day of birth.
of 1999, VCAL has been used for about twelve years, but could
of course still have bugs. If you find a suspected bug, please
contact Markandeya Rsi Dasa at this e-mail address: <email@example.com>.
Some basic astronomy
The movements of the moon and sun
the perspective of an observer on earth, the sun and moon
and stars are moving around the earth every day. If we look
at the sky at night, as the hours pass we will see the moon
and stars gradually move west across the sky, seeming to move
together. But as several nights go by, we may notice that
the position of the moon in relation to the stars moves towards
extent of this relative movement comes to roughly 13 degrees
per day. Thus the moon will complete a full rotation through
the belt of stars, called the zodiac, in about one month.
similar situation is true for the sun. Because the stars are
too weak to be seen during the day, we cannot see the sun
and the stars simultaneously. But if we could, we would see
the sun moving gradually against the background of the stars.
The sun, however, moves more slowly than the moon -- only
about 1 degree each day. So we would have to wait longer to
observe the difference. For the sun to come back to the same
group of stars on the zodiac takes one year.
The definitions of solar and lunar months and years
can define a month and a year in two basic ways: by the movement
of the moon and by the movement of the sun.
The solar month and year
Vedic solar month lasts the time it takes for the sun to traverse
a complete sign of the zodiac. The zodiac has twelve signs,
so each sign covers an angle of 30 degrees. Because the sun
moves across the zodiac by about 1 degree each day, to traverse
a complete sign takes about 30 days -- more exactly, 30.4
days. Twelve such months make one solar year -- that is, a
little more than 365 days. In other words, a solar year is
the time it takes for the sun to start from any group of stars
and return to it. Such a year stays synchronized with the
The lunar month and year
lunar month and year are slightly more complex. The Vedic
calendar defines the lunar month in terms of the phases of
the moon. We know that the phases of the moon change. The
moon is sometimes full, sometimes half, and sometimes new,
depending on how much of the moon we on earth can see lit
up by the sun. When the sun and moon are close to one another
on the zodiac, the side of the moon illuminated by the sun
will mainly have its back to us. So we will see only a sliver,
and most of the moon will seem dark. Then again, when the
sun and moon are on opposite sides of the zodiac, the side
of the moon we see from earth will be fully illuminated, so
we will see a full moon. All other positions of the sun and
moon result in the other, intermediate lunar phases.
the Vaisnava calendar a month starts the day after one full
moon and continues through the next full moon. This takes
about 29.5 days.
as 12 solar months make one solar year, 12 lunar months make
one lunar year. Since one lunar month takes 29.5 days, 12
such months will take about 12 times that long -- that is,
lunar year is 11 days shorter than the 365-day solar year,
so although the month synchronizes with the lunar phases,
the year does not synchronize with the seasons. Counting by
the solar calendar, every solar year the lunar year will begin
11 days earlier. So, to synchronize the lunar year with the
seasons, the Vedic calendar adds an extra month about every
third year, according to certain rules. In this way the lunar
and solar years stay in synch.
The Pancanga, or the Vedic calendar
Vedic calendar is called Pancanga. The word Pancanga indicates
that the calendar consists of five parts, or tells about five
elements. These elements are vara (the day of the week), tithi
(the lunar day, or phase of the moon), karana (half a tithi),
naksatra (the position of the moon in the zodiac), and yoga
(a measurement derived from the positions of the sun and moon).
For normal use of the calendar, one need not understand all
these elements. But some of them are described as follows.
we have discussed, the lunar month marks the time from one
full moon to the next. The lunar month is divided into 30
parts, called lunar days, or tithis. The tithis are simply
the different phases of the moon. Thus the first tithi starts
at the moment when the moon is full -- that is, when the angle
between the moon and the sun is 180 degrees and it continues
until the angle has increased 12 degrees. Then, that much
less of the moon seems bright to us: the moon is no longer
the second tithi starts, and it continues until the angle
between the sun and moon has increased 12 degrees more. Slightly
more of the bright side of the moon now has its back to us,
and so the moon is even less full.
15 such tithis have passed, the angle between the sun and
the moon has increased by 180 degrees. This time the bright
side of the moon cannot be seen at all, and so we have a new
moon. Then 15 more tithis gradually pass, and the moon again
becomes full. When 30 tithis have thus passed, the month ends.
period when the moon wanes, or decreases in size, is called
krsna paksa ("the dark fortnight"), and the period when it
waxes, or increases, is called sukla paksa or gaura paksa
("the bright fortnight"). The words Krsna and Gaura used here
are specific to the Gaudiya Vaisnava tradition.
lunar calendars start the month from the 0-degree position
-- that is, directly after the new moon. Such calendars are
called mukhya candra. Other calendars, such as the one used
by the Gaudiya Vaisnavas, start directly after the full moon,
with the Krsna paksa. Such calendars are called gauna candra.
for the new moon and the full moon, the names of the tithis
are simply counting words: pratipat, dvitiya, trtiya (first,
second, third), etc. These names are the same for the tithis
occurring during Krsna paksa (the dark period of the moon)
and the gaura paksa (the bright period). The new moon is called
amavasya, and the full moon purnima.
paksa Gaura paksa Tithi Name Tithi Name
15 Amavasya (new moon)
15 Purnima (full moon)
Because the speed of the moon in relation to that of the sun
is not constant but varies, a tithi is not a fixed duration
of time. Its length fluctuates between 19 and 26 hours. Therefore,
since a lunar tithi does not correspond to the 24-hour solar
day, a tithi may start at any time of the day.
are certain tithis on which the followers of the Vedic culture
follow various observances or celebrations. On what day is
such a tithi to be observed? The general rule is that one
will celebrate a tithi on that day whose sunrise falls within
the tithi, though sometimes other rules come into effect.
Ekadasi tithi is especially important, and special rules determine
when to observe Ekadasi. Special rules also sometimes apply
for festivals such as Sri Krsna Janmastami.
previously mentioned, in the sky the belt of stars called
the zodiac is divided into 12 signs, which cover 30 degrees
each. There is also a way of dividing the zodiac into 27 parts,
which cover 13-1/3 degrees each. These parts are called naksatras.
moving over the zodiac, the moon continuously passes through
these naksatras one by one. In the Vedic calendar, naksatra
simply refers to the naksatra within which the moon is present
at sunrise on any particular day.
and naksatras can easily be understood in relation to the
phenomena in the sky. Tithi is the phase of the moon, and
naksatra marks the position of the moon. But yoga is not easily
understood in a similar way. The yoga is determined by adding
the angle or longitude of the sun and moon, reducing the sum
to fit in the circle of 360 degrees (by subtracting 360 degrees
if needed), and then dividing the resultant number by 13-1/3
degrees. Like the naksatras, the yogas are also 27 in number.
Reasons to follow a lunar calendar
the Vaisnava calendar the times for various celebrations are
determined by the tithi, sometimes with naksatra and other
elements of the calendar taken into account.
scholars who have analyzed the old Indian calendar systems,
both lunar and solar, have concluded that the lunar system
is the more ancient.
lunar phases are known to influence agriculture, and according
to scriptures like Manu-samhita (The Law of Manu) they also
influence more subtle aspects of human life.
Traditional and modern methods of calculation
the astronomical calculations needed to make a Pancanga were
done according to one of the astronomical texts such as Surya
Siddhanta. The methods described in Surya Siddhanta are basically
quite similar to modern astronomical methods for ascertaining
the positions of the planets. The main difference is that
Surya Siddhanta has a simpler model. Such a model is needed
if the calculations are to be done by hand in a practical
methods of Surya Siddhanta could be used by a skillful person
at any time, without the need for modern equipment. All that
was needed were some observatory instruments that could be
built without high technology. These instruments were used
regularly to check that the calculations tallied with observable
reality. When a difference appeared after some time, corrections
were made to the astronomical constants in the formulas. With
this system, fairly good results were obtainable even though
the astronomical model was simple. Its accuracy cannot be
compared to that obtained by modern methods, but for the purpose
of astrology and creation of calendars it sufficed.
computer program uses formulas that give an accuracy of 1
minute of arc for the longitude of the sun and 2 minutes of
arc for the longitude of the moon. When determining ending
times of tithis these errors can result in a maximum error
of 5 minutes of time. The average error is about 3 minutes.
Such an error will report an Ekadasi (the eleventh tithi)
on the wrong date roughly once every 20 years.
Some comments on interpreting the Vaisnava calendar
Gaudiya Vaisnava tradition, the years are counted from the
appearance of Lord Sri Krsna's incarnation as Lord Sri Caitanya
Mahaprabhu. Lord Caitanya is also known as Gaura, so the year
is called "Gaurabda," "the year of Lord Caitanya."
month, or "masa," is known by a name of Visnu. The months,
the Sanskrit names by which they are commonly known in India,
and their rough equivalents according to the Gregorian calendar
are listed as follows:
Names of years and months
When to observe Ekadasi
the eleventh tithi, has special importance. In the scripture
Caitanya-caritamrta (Madhya-lila, chapter 24), Lord Caitanya
Mahaprabhu instructs Sanatana Gosvami regarding the Vaisnava
regulative principles. In text 342 Lord Caitanya says:
should recommend the avoidance of mixed [viddha] Ekadasi and
the performance of pure Ekadasi. You should also describe
the fault in not observing this. One should be very careful
as far as these items are concerned. If one is not careful,
one will be negligent in executing devotional service."
described in the book Hari Bhakti Vilasa, viddha (mixed) Ekadasi
takes place when the eleventh tithi starts before sunrise
but the tenth tithi still presides at the beginning of brahma
muhurta (the auspicious period that starts an hour and a half
Ekadasi it is traditional to fast. But under certain conditions,
called mahadvadasi, one fasts not on the Ekadasi but on the
next day, the dvadasi, even though the Ekadasi is suddha,
or pure, and not viddha, or mixed. There are eight mahadvadasis.
calendars produced by this program make it easy to see when
to observe Ekadasi. The Ekadasi fast should be observed on
the day called suddha (pure) Ekadasi, or alternatively on
Mahadvadasi, even if the previous day is called Ekadasi. All
this is clarified by the asterisk (*), which indicates a fast,
at the right margin of the calendar.
"Break fast 05:18 - 09:34" and "Daylight-savings not considered"
complete the proper observance of Ekadasi, the next morning
one should end the fast after the first time given in the
calendar and before the second time. The calendar gives these
times according to the standard time of the place for which
the calendar is made.
the summer, many locations do not follow standard time, but
instead move their clocks an hour ahead (or sometimes more)
to make more use of the hours of daylight. So, for example,
5 o'clock in the morning becomes 6 o'clock instead. The Vedic
Calendar program does not take such daylight-saving time into
account. So for days when your location uses daylight-saving
time, you must adjust the times given by the calendar. Generally,
this means that when daylight-saving time is in effect you
should add an hour to the times given.
Double or no tithi
studying the calendar, you may find that sometimes a tithi
is skipped and sometimes one tithi comes on two consecutive
days. There is nothing wrong with this. For each day, the
calendar just shows which tithi (moon phase) prevails at the
time of sunrise. Sometimes a given lunar phase may begin after
one sunrise and end before the next, and therefore on the
calendar that tithi appears missing. Or sometimes one lunar
phase extends throughout two sunrises in a row, and therefore
that tithi appears twice.
person's birthday is determined by the tithi prevailing at
the moment the person was born. Every year thereafter, the
day to celebrate as the birthday should be the day whose sunrise
occurs during that same tithi. If the tithi prevails on two
consecutive sunrises, the sunrise that has the same naksatra
as at birth will be the proper day for celebration. If neither
sunrise occurs with that naksatra, then the latter of the
two days should be chosen. If there is no day whose sunrise
occurs during that particular tithi, then the day within which
the tithi falls should be chosen as the day of celebration.
for example, that a person's appearance day should be celebrated
on dvitiya tithi in the month of Kesava and that for the month
of Kesava the calendar lists two dvitiya tithis, one after
another. And suppose that the naksatra that prevailed at birth
is not present. Then the second dvitiya should be chosen as
the day of celebration. If the calendar shows no dvitiya at
all, then the appearance day should be celebrated on the day
listed as pratipat, because the dvitiya phase of the moon
will occur during that day.
means the time when the sun enters a sign of the zodiac. If
you are conversant with astrology, you might wonder why the
calendar shows the sun entering the various signs of the zodiac
at times different from those given in Western astrology.
This is one of the differences between the two kinds of astrology,
Western and Vedic. The difference pertains to a certain angle
called ayanamsa, which is presently around 23 degrees. The
explanation of ayanamsa can be found in books about Vedic
Names for the signs of the zodiac
are the Sanskrit names for the signs of the zodiac,
alongside their English counterparts.
wish you a life fulfilled with good Vaisnava years. Hare Krsna.
(c) 1999 The Bhaktivedanta Book Trust International, Inc.
All rights reserved.
FESTIVAL DAYS FROM THE VAISNAVA CALENDAR
Explanations compiled by Krsna-priya Devi Dasi
(Vaisnava Academy for Girls, Alachua, Florida, USA)
This Vaisnava calendar uses the terms "appearance"
and "disappearance" to denote the birth ("appearance")
and the departure ("disappearance") of great souls
and incarnations of the Lord.
-- the appearance day of Radha-kunda and Syama-kunda,
sacred ponds that are the bathing places of Srimati Radharani
and Lord Krsna in Vrndavana.
Rasayatra -- Lord Balarama's springtime rasa dance
with His cowherd girlfriends.
Daityaraja Puja -- the festival commemorating Bali
Maharaja's surrender to Lord Vamanadeva, the dwarf incarnation
of Lord Krsna. A Deity of Vamana is worshiped.
-- the appearance anniversary of Bhismadeva, the
"grandfather" of the Pandavas.
Yatra -- a festival during the hot season in India
in which the Deities are covered with sandalwood paste (candana)
to cool Them. (This is generally impractical in the West,
where it is cold during this time.)
Masa -- the month of Damodara. Throughout this month,
devotees commemorate the pastime of naughty Lord Krsna's being
bound with ropes by mother Yasoda. Devotees offer lamps daily.
Dipavali, or Diwali (and Kalipuja) -- a commemoration
of Lord Rama's return from exile to Ayodhya, His capital,
following the defeat of the demon Ravana. (Vaisnavas don't
regularly observe Kalipuja, the worship of Durga Devi.)
Pancami -- a festival held three days after Ratha-yatra
to commemorate Srimati Rukmini Devi's visit to Vrndavana to
bring Lord Krsna back to Dvaraka.
Puja -- the appearance anniversary of Ganga Devi,
the goddess of the River Ganges.
Sagara Mela -- a festival observed especially at
the confluence of the Ganges and the Bay of Bengal. Kapilasrama,
the asrama of Lord Krsna's incarnation as Kapiladeva, the
son of Devahuti, is located at this place. The festival commemorates
King Bhagirathi's bringing the River Ganges down from the
celestial planets to the ocean and the lower worlds.
Purnima -- the appearance anniversary of Lord Sri
Caitanya Mahaprabhu, who is Krsna Himself in the role of His
own devotee. He appeared in 1486 in Mayapur, West Bengal.
or Gosthastami -- After previously having grazed
the calves, on this day Krsna first went out to graze the
cows. In this way He became a gopa, a cowherd boy. On this
day the gosalas (cow pens) are cleaned and the cows worshiped
and offered prasada (santicified food) by the devotees.
Puja -- the festival commemorating the worship of
Govardhana Hill by the residents of Vrndavana and Lord Krsna's
lifting the hill.
Puja, or Go-krda -- On this day, according to Hari-Bhakti-Vilasa,
one should decorate the cows and bulls, make them run, and
have the bulls plow the field.
Marjana -- the cleansing of the Gundica temple in
Jagannatha Puri, India.
(Vyasa) Purnima -- the appearance anniversary of
Srila Vyasadeva, the compiler of the Vedic literature.
of ISKCON in New York -- Srila Prabhupada founded
ISKCON, the International Society for Krishna Consciousness,
Saptami -- The day when the sage Jahnu released the
River Ganges after swallowing her. On this day, if possible,
one should worship the Ganges and bathe in her waters.
Puja -- the day for worship of a form of Mahamaya
called Jagaddhatri, "the maintainer of the material world."
(Vaisnavas do not usually observe this festival.)
of Jagannatha Misra -- the day the father of Lord
Caitanya Mahaprabhu performed the celebrations for Lord Caitanya's
vrata -- a vow to observe austerities to please Katyayani
Devi, or Yogamaya Devi, the spiritual energy of Lord Krsna.
Janmastami -- the appearance anniversary of Lord
Sri Krsna, the Supreme Personality of Godhead.
Phula Dola, Salila Vihara -- a summer boat festival
for the Deities of Sri Sri Radha-Krsna.
Pusya abhiseka -- During the morning puja, or worship,
the Deity or a salagrama is bathed in pure ghee. Srila Prabhupada
once explained the festival this way: "Krishna was just
a toy in the hands of the Gopis, so one day the Gopis decided
that we shall decorate Him. Pusyabhisheka means a ceremony
to decorate the deity profusely with flowers, ornaments, cloths.
After there should be lavish feasting and a procession through
the streets, so that all the citizens should see how beautiful
Saradiya Rasayatra -- Lord Krsna's autumn rasa dance
with His girlfriends.
Vasanta Rasa -- Lord Krsna's springtime rasa dance.
Sasti -- The appearance day of Lalita-sakhi, the
intimate confidante of Srimati Radharani.
Puja -- worship of Laksmi Devi, the consort of Lord
Visnu (not observed by Gaudiya Vaisnavas).
-- the festival observed by Nanda Maharaja, Lord Krsna's father,
to celebrate Lord Krsna's appearance.
Caturdasi -- the appearance anniversary of Lord Nrsimhadeva,
Lord Krsna's incarnation as half-man, half-lion.
Cida Dahi Utsava -- Srila Raghunatha Dasa Gosvami's
chipped- rice-and-yogurt festival for Lord Caitanya and His
associates. Celebrated especially in Panihati, West Bengal.
-- the appearance anniversary of Srimati Radharani,
the eternal consort of Lord Krsna.
Govinda Jhulan Yatra -- the swing festival of Radha-Krsna.
The Deities ride on an elaborately decorated swing.
Kunda prakat, snan dan -- the appearance anniversary
of Radha- kunda, the bathing pond of Srimati Radharani in
Vrndavana. Devotees bathe there especially on midnight of
Ramana Devji appearance -- the appearance of the
Deity of Lord Krsna worshiped by Srila Gopala Bhatta Gosvami.
Yatra -- The chariot festival in which Lord Krsna
in the form of Lord Jagannatha rides with Lord Balarama and
Subhadra Devi in Jagannatha Puri, India.
Vijayotsava -- Lord Ramacandra's victory over the
demon Ravana. A large effigy of Ravana is ceremoniously burned.
and Tulasi Jala Dan -- During the hot season in India,
a pot of dripping water is placed over Tulasi and Salagrama
to keep them cool. (Generally, this is impractical in the
West, where it is cold during this time.)
Puja -- worship of the goddess Sarasvati (not generally
observed by Vaisnavas).
Ratri -- worship of Lord Siva. Devotees may bathe
a Siva-linga in water and panca-gavya (five substances from
the cow) and offer Krsna-prasada to Lord Siva. Fasting is
optional for Vaisnavas.
Yatra -- On this full-moon day, sixteen days before
Ratha- yatra, Lord Jagannatha is bathed. He becomes sick and
is confined to rest for fourteen days. He is then offered
special care until He comes out for Ratha-yatra.
Prabhupada's acceptance of sannyasa -- Srila Prabhupada
accepted sannyasa, the renounced order of life, from Sri Srimad
Bhakti Vijnana Kesava Goswami Maharaja in Mathura, India,
Prabhupada's arrival in the USA -- Srila Prabhupada
arrived in Boston on September 17, 1965.
Prabhupada's departure for the USA -- On this day
in 1965, Srila Prabhupada left Calcutta aboard the steamship
Prabhupada's disappearance day -- Srila Prabhupada
left this world on November 14, 1977, in Vrndavana, India.
Devotees observe this anniversary with personal remembrances
of Srila Prabhupada, readings from his biography, and so on.
Vivaha -- the wedding of Salagrama and Tulasi Devi.
Dvadasi -- the appearance anniversary of Lord Vamanadeva,
the dwarf incarnation of Lord Krsna.
Pancami -- the first day of spring. On this day,
the Deities are offered many flowers, leaves and new shoots
(c) 1999 The Bhaktivedanta Book Trust International, Inc.
All rights reserved.