Islamic Calendar Development for North America

Every calendar except one, at any time in the entire history of the
world, has had to make corrections by either adding or subtracting time.
The Jewish, Chinese, or Hindu calendars add a thirteenth month periodically,
to bring the lunar calendar in line with the solar calendar. This is called
"intercalation" or "Nasi" (in Arabic). Two kinds of
Nasi were in practice at the time of Prophet Muhammad (Salla Allahu alayhi
wa Sallam). One was inserting a thirteenth month, and the other was transposing
a sacred month with another for certain social or political advantages.
During the Prophet's farewell message, two revelations regarding the Islamic
calendar were given to humankind.

(Qur'an, 9:36): "Number of months in sight
of Allah is twelve (in a year). So ordained by Him, the day He created
the heavens and the earth."

(Qur'an, 9:37): "Verily the transposition
(of a prohibited month or intercalation) is an addition to Unbelief."


This indicates that the use of a calendar with intercalation is against
nature and disliked by Allah (Subhanahu wa Ta'ala). Intercalation of a
month is used by the Jewish, Chinese, and Hindu calendars, while Gregorian
calendar uses intercalation of days in several months to increase the number
of days to 30 or 31. The one calendar that does not add or subtract time
is the Islamic calendar. Despite the figures presented by some calendars,
the reality is that among all the prevailing calendars in the world, the
Islamic calendar is the oldest in practice in its original form without
any correction or modification. The year 5757 of Jewish calendar or the
year 1997 of the Gregorian calendar should not mislead one. These calendars
have had adjustments of adding or subtracting days or months. The Gregorian
calendar was last corrected replacing the Julian calendar by dropping ten
days in the year 1582 CE in the Catholic world, or by dropping 11 days
in the year 1752 CE in England, and its colonies including the United States.


The Islamic calendar, because of its inherent cycles of the visible
crescent, does not require any corrections, and has remained intact in
its principle since it was given to humankind by Allah (Subhanahu wa Ta'ala)
through His Messenger, Prophet Muhammad (Salla Allahu alayhi wa Sallam).
Thus, there is a definite need to develop an Islamic calendar. The guidance
regarding the reckoning of time, comes from Qur'an, and Hadith. In the
Qur'an, Allah (Subhanahu wa Ta'ala) says:

(Qur'an, 10:5): "It
is He who made the sun a radiance and the moon a light and determined their
stations that you might know the number of years and reckoning of time."

(Qur'an, 36:39): "Neither the sun may reach
the moon nor night will precede the day...each in special orbit is swimming
around according to its law."

(Qur'an, 55:5): "The sun and moon follow
courses exactly computed."

(Qur'an, 2:189): "They ask you about the
crescent moons, say: they are signs to mark fixed periods of time for the
people and for pilgrimage."

Thus, in the Islamic calendar the visible waxing crescent moon marks
the beginning of each new month, and there are 12 months in a year. The
year count started from the year of the Messenger's migration to Madinah.
According to Abu Hurayra, the Messenger said: "Fast to its sighting
(ru'yah) and break your fast to its sighting, and if it is obscured to
you by clouds, then count the month to thirty days." (Bokhari and
Muslim). The word ru'yah has been used in the language of the Qur'an for
"vision" by knowledge. This is evident.

(Qur'an, 105:1), "See thou not how thy Lord
had dealt with the people of the elephant?"

and (Qur'an, 99:6) "See thou not how thy
Lord dealt with the 'Ad people?"

Here, Allah (Subhanahu wa Ta'ala) is questioning the Messenger; "Do
you not know?" "Are you not aware of?" etc., while the Messenger
was not even born at the time of the people of the elephant or the people
of 'Ad. Therefore, the Hadith may mean "Fast to the vision (by eye
or by knowledge) of the new crescent." Moreover, the same concept
(absolute knowledge) is precisely what Muslims have used for centuries
to determine the daily prayer times by calculations, despite the fact that
in the past Muslims used direct vision of the sun, the simplest and only
method available at the time, to ascertain the prayer times. However, with
the advent of the clock and wristwatch, no longer does a Muslim go out
to check whether an object's shadow has reached its length or whether the
sun has gone below the horizon. Instead, he simply looks at his watch and
uses prayer times (calculated years in advance). Thus, observation by direct
vision was not the criterion; rather, it was merely a means of attaining
certainty. In other words, the method has changed (the use of calculation)
while the basis for prayer times (the solar position) has not. All the
Muslims accept this methodology without hesitation or argumentation. The
same principle may be applied to the precise orbit and rotation of the
moon since both the sun and the moon move with sufficiently known precision.


Furthermore, the Messenger warned his companions that they were unlettered
people who could "neither read nor count" (Hadith, Muslim) and
that they must therefore prefer to sight the moon rather than calculate
its position although if the day were cloudy, they could calculate it by
counting 30 days from the previous crescent. Later, when the Islamic civilization
flourished, Muslims could do more than count and write. They invented spherical
astronomy and with the advances in astronomy and computer technology, Muslims
are now able to calculate the dates when a new crescent could be sighted,
and when it is impossible to sight the moon. When sighting was more reliable
than calculation, the Ummah was told to rely on sighting. Today calculation
is more reliable than sighting, hence, that should be used.

Lunar Crescent Visibility:

Muslim astronomers have worked on this subject from 700 CE to the present.
Among early Muslims the contributions made by Habash al-Haasib (740-840
CE), Muhammad ibn Musa al-Khwarizmi (830 CE), al-Farghani (850 CE), Muhammad
ibn Gabir al-Battani (850-929 CE), and Abu Rayhan al-Biruni (11th century
CE) are worth noting. In recent times, especially during the last three
decades, scientists and astronomers both Muslims and non-Muslims have diligently
worked to develop algorithms to calculate the expected dates for moon sighting.
E.S. Kennedy (The lunar visibility theory of Ya'qub Ibn Tariq. Journal
of Near Eastern Studies, 27, 126; 1968.) documented the work on the lunar
visibility theory of Ya'qub Ibn Tariq of 8th century CE. F. Bruin, (The
first visibility of the lunar crescent, Vistas in Astronomy, 21, 331-358,
Pergamon Press, 1977) explained the first visibility of the lunar crescent,
giving a good scientific perspective for the problem. S. K. Abdali, (On
the crescent's visibility. Al-Ittihad, January-July, 25-31, Muslim Students'
Association, Plainfield IN, 1979) presented his views on crescent's visibility
analyzing some of the work done by others. Dr. Muhammad Ilyas (A modern
guide to astronomical calculations of Islamic calendar, times, and Qibla.
Berita Publishing Sdn. Bhd., Kuala Lumpur, 1984) developed a few preliminary
concepts for developing a crescent visibility algorithm. D.A. King (Ibn
Yunus on lunar crescent visibility. Journal of History Astronomy, 19, 155-168;
1988) wrote a paper on the work of Ibn Yunus on lunar crescent visibility.
Ilyas (Astronomy of Islamic times for the twenty-first century. Mansell
Publishers, London, 1989) presented his further work on lunar visibility
and the Islamic calendar. Yallop of Royal Greenwich Observatory (RGO) with
his criterion of azimuth and altitude has been producing annually an RGO
sheet showing the place of first visibility for every lunation. Ithaca,
New York based Dr. Omar Afzal has been refining his criterion from 1979
onwards by collecting information on moon sighting from all over the world
through the Committee for Crescent Observation.

With the benefit of the work done by these notable scientists, the author
carried on this research further by compiling published crescent observation
data from 1859 to 1990 CE, and data collected by the Committee for Crescent
Observation from 1979 to the present. A database for crescent observation
containing over 800 data points for sighting or nonsighting was analyzed
with the algorithm developed by the author. All the important parameters
that affect visibility were calculated for every single observation including
arc of light (elongation), moon's topocentric altitude above horizon (which
includes the effects of atmospheric refraction, the semi diameter of the
moon, and the parallax correction), width of crescent, distance of the
moon from the earth, and distance of the earth from the sun. Having calculated
these parameters for all the analyzed data, a correlation was established
for the threshold values that make a crescent visible.

An algorithm (Shaukat's criterion) is thus developed (1988-1997 CE)
to calculate visibility curve (Lunar Date Line) on the map of the world.
This algorithm predicts the visibility of the new crescent better than
the criteria developed by others (Yallop, Schaefer, Ilyas, Abdali, and
Afzal). Shaukat's criterion has proven to match with actual sighting every
month since August 1992, as documented by an independent periodical, "Islamic
Perspectives," published monthly by Washington DC chapter of Islamic
Circle of North America (ICNA). Shaukat (Moon sighting: Hand in hand with
calculations. Islamic Horizons. January/February, 37. 1995) showed how
the calculations go hand in hand with actual sighting. In another article,
Shaukat (1995) provided a review on a book written by Ilyas (New moon's
visibility and International Islamic calendar for the American region.
The American Journal of Islamic Social Sciences. 12 (2), 279-284), "New
Moon's Visibility and International Islamic Calendar." Shaukat (Islamic
Lunar calendar. Insight, a Quarterly Journal, 11 (2 & 3), 15-17. Islamic
Foundation for Education & Welfare, Sydney, Australia.1996) provided
a sound basis for the development of an Islamic lunar calendar.

Development of Islamic Calendar:

The continuous efforts by the author in the last two decades for refining
the visibility criterion have reached to a point where sufficient agreement
exists between actual sighting and calculations for sighting. This criterion
can now be used to prepare an Islamic calendar for a specific region. Thus,
using this concept, a regional Islamic calendar for North America is calculated
and presented here. In such calculations, there is a small percentage of
uncertainty (about once a year on an average) when the visibility curve
falls just west of California, in which case, a note can be added in the
calendar indicating that although it is improbable to see the moon on that
evening, there is a small chance that the moon could be sighted on West
coast of North America on that day. Only for such a case do we have to
wait for sighting confirmation. For all other months the calculations of
sighting are quite definite without ambiguity, and we do not have to wait
for sighting, although the sighting would eventually be confirmed. Table
1 shows Gregorian dates for the first day of Islamic months with the convention
that Islamic date begins on the evening before the Gregorian date shown.
This is based on the visible crescent moon assuming North America as one
horizon (Matla').

Table 1 Islamic Calendar For North America
___________________________________________________________ ____
Month -- Year 1418 AH 1419 AH
___________________________________________________________ ____

1st Muharram 05-08-97 (Thu) 04-28-98 (Tue)
1st Safar 06-07-97 (Sat) 05-27-98 (Wed)
1st Rabi-al-Awwal 07-07-97 (Mon) 06-26-98 (Fri)
1st Rabi-al-Thani 08-05-97 (Tue) 07-25-98 (Sat)
1st Jumada-al-Oola 09-04-97 (Thu) 08-24-98 (Mon)
1st Jumada-al-Akhir 10-03-97 (Fri) 09-22-98 (Tue)
1st Rajab 11-02-97 (Sun) 10-22-98 (Thu)
1st Sha'ban 12-01-97 (Mon) 11-21-98 (Sat)*
1st Ramadan 12-31-97 (Wed) 12-20-98 (Sun)
1st Shawwal 01-30-98 (Fri)* 01-19-99 (Tue)
1st Zul-Qa'da 02-28-98 (Sat) 02-18-99 (Thu)*
1st Zul-Hijja 03-29-98 (Sun) 03-19-99 (Fri)
___________________________________________________________ ____

* very small chance that the first day of Islamic month may be on the
day before.

In the modern age of communication, we all need to plan, schedule, and
announce various religious occasions. An Islamic calendar based on calculations
of sighting that has proven to be sufficiently accurate for practical purposes
would compel us to start the Islamic months correctly without chaos and
confusion. Calculations for a visible crescent meet the intent of Shari'ah,
and are effective means for producing an Islamic calendar for any defined
Matla'. Benefits of developing such a calendar greatly surpass the chaotic
consequences created by mistaken and erroneous claims of sighting, and
having to wait past midnight to get the decision from authorities like
Islamic Shura Council of North America, or the confirmed news of sighting.

Khalid Shaukat is ISNA consultant on moonsighting.