Our Goal

1
Our Goal

• The goal of the Islamic Computational Astronomy
  Network (ICAN) is to
• Set up a single, global standard for the Islamic
  calendar based on
• Islamic requirements
• Astronomical facts
• Results
• The entire Islamic world can establish a uniform
  global Hijri calendar
• Muslims everywhere in the world have the same
  Hijri dates (not two or three)

2
The Format of the Talk

• The talk will be broken down into three parts
• PART 1 CALENDARS
• How a calendar is made
• How Muslims fixed their calendar
• Question and answer session
• PART 2 THE MOON
• How the moon is sighted
• Question and answer session
• PART 3 A NEW GLOBAL CALENDAR STANDARD
• A new proposed global standard
• Question and answer session

3
Part 1 - Calendars
Muslims in North America follow THREE Hijri
Calendars - Calendars from ME countries. - Moon
SEEN anywhere in 48 contiguous states - Locally
visible moon (CT Council of Masajid) Muslims
started Ramadan 2005 on four solar days/dates
(instead of one lunar day/date). Oct. 3 Monday
Nigeria (some Sunday, Oct. 2 also) Oct. 4
Tuesday S. Arabia, M East, followers of Saudi
dates) Oct. 5 Wed. Australia, Indonesia,
Malaysia, Brunei, Turkey, Africa, Europe,
Americas Oct. 6 Thurs. Bangladesh, India,
Pakistan, Central Asia Eid al-Fitr 2005 was
celebrated on four different days/dates Nov. 2
Wed Nigeria, Libya Nov. 3 Thurs. S. Arabia, M
East, Indonesia, EU, USA (ISNA) Nov. 4 Friday S.
Africa, UK, Canada, USA, India, Pakistan Nov. 5
Saturday Northern India, etc. Why
this chaos? Muslims do not agree on when to
begin an Islamic month.  
4
Calendar Making Options

• You can make a calendar by using the sun or the
  moon
• People have used different methods to make either
  calendar for thousands of years
• The Islamic calendar is lunar, unlike the solar
  calendar
• Lunar calendars
• Babylonian
• Jewish
• Hindu
• Chinese
• Islamic

• The New Moon time and date could be fairly
  accurately calculated for more than 2000 years.
• None of the lunar calendars starts from the New
  Moon (Conjunction)

5
Two Major Challenges

• Accurately predicting moons earliest visibility
• Uniform global fixed dates of Hijri Calendar

6
Calendars are Global, not Tri-Zonal
7
Why Muslim Dates Are a Mess?

• Some start Ramadan
• By a visible moon (India, Pakistan, Bangladesh,
  Morocco, S. Africa)
• From the Moonset after the sunset (Saudi Arabia,
  Egypt and the M. East)
• On the New Moon date (Libya, Tunis, etc.)
• Moons fixed elongation or altitude (Indonesia,
  Malaysia, Turkey, etc.)
• Only dates based on the earliest visible moon at
  sunset fulfill the Shariah requirements.
• Do we have to see the Hilal to start and end
  Ramadan and other months? YES.

8
Lunar Calendar

• A lunar calendar depends on the moons phases
• Earlier, you could not predict exactly when and
  where a moon would be seen
• Now we can do this with modern computers
• Before the modern communication age, people
  observed their lunar calendars locally. It was
  not possible to coordinate between towns,
  countries and continents
• If it was cloudy, people couldnt see the moon.
  They had to complete 30 days though the moon was
  seen in the nearby town
• CONCLUSION
• The old ways of calendar-making, where every
  village and town observed its own dates, is no
  longer correct. Tri-zonal or bi-zonal calendars
  are equally invalid.

9
QUESTION AND ANSWER SESSION
10
Part 2 - Quran Hilal is Miqaat
11
Hilal and Not the New Moon
12
Ittihad vs. Ikhtilaf al-Matali
13
Lunar Calculation is Fine
14
Moon-Sighting Controversies
------?
15
Moon-Sighting Involves Two Parts

• There are two parts to moon-sighting
• How the moon revolves around the Earth
• How, when, and where people on the ground see the
  moon

Moon Basics

• The moon revolves around the earth (need an
  animatic to show this)
• As the moon moves around the earth, its phases
  change from the new moon to full moon and back to
  new moon

16
Computed New Moons for 2000-2019
17
Data for Ramadan 1427
18
Moons Rotation Around Earth

19
Sidereal Synodic (Conjunction) Month

• The moon rotates around Earth
• Sidereal rotation takes 27 Days, 7 Hrs, 43 Mins,
  11.6 Sec
• Synodic month (Conjunction to Conjunction) is 29
  Days, 12 Hrs, 44 Mins, 2.9 Sec
• The moon is not visible on the conjunction date

20
This is the New Moon (Geocentric Conjunction)

• Arabic term for the conjunction phase of the moon
  is not Hilal but al-Qamar al-Mawlid (new
  born-moon)
• Hilal (plural Ahilla) is the earliest visible
  waxing crescent moon after Mahaaq
• Mahaaq are the dark nights between two lunar
  months when the moon is hidden for observers from
  the surface of the earth.
• The New Moon (Geocentric conjunction) could not
  begin a lunar month because
• The New Moon occurs at all times of day and
  night.
• A date has to start always from a fixed point of
  time.
• Every month the New Moon occurs at a different
  point on the globe

New Moon
Hilal
21
A NASA Photograph at the New Moon Phase

• The infra-red scan of the moon at the conjunction
  shows a full black moon with no crescent

22
This is the Islamic New Moon (Hilal)

• Hilal (plural Ahilla) is the visible waxing
  crescent moon of the first two or three days.
• The term is derived from the root Halla to
  raise voice at the first sight of the waxing
  crescent moon

23
Moons Paths in Various Months

• From different locations on Earth in different
  seasons, the crescent moon appears of a different
  shape and at different heights.
• If the moon is not seen on the 29th evening then
  on the next day it appears 24 hrs. bigger,12
  degrees higher and brighter. It stays in the sky
  52 min. longer too.
• It does not mean the moon could be seen in the
  previous evening.

24
Fixing Dates of Ramadan and Eidain

• Islamic dates are not fixed because Islamic month
  may be 29 or 30 days long
• Islamic day and date begin at sunset after a moon
  is seen
• The earliest visible moon can now easily be
  computed for any point on Earth
• Earliest visibility may be by naked eye or
  binoculars followed by naked eye or telescope
  followed by binoculars or telescope only

25
The New Moon or Hilal?

• The New Moon (Geocentric conjunction) cannot
  begin a lunar month (as Qaradawi, Shakir and
  others believe) because
• The New Moon occurs at all times of day and
  night. (A date must always start from a fixed
  point of time)
• Every month the New Moon occurs at a different
  point on the globe
• A rotating dateline and floating time made the
  New Moon useless for any lunar calendar

• The Quran, the Sunnah and Fiqh make the earliest
  visible waxing crescent moon (Hilal) the fixed
  point (Miqaat) to begin an Islamic month (2189)
• Can we accurately predict moons earliest
  visibility?
• Yes. For any region, though not for every village
  on the Earth)
• Visibility should be consistently verified by
  naked-eye sighting

26
How Astronomers Compute Visibility

• The Moons earliest visibility is no longer a
  scientific inquiry, and there is no scientific
  test to prove or disprove a sighting claim. So
  how to determine the first date of an Islamic
  month? Since ancient times, astronomers have
  tried to predict the likelihood of seeing the
  waxing moon by defining minimum visibility
  criteria. Monzurs MoonCalc currently supports 13
  such criteria.
• Babylonian.................... Age at
  sunset24hrs Lag48 min.
• Fotheringham (1910) Alt, Rel Azi
• Maunder....... (1911) Alt, Rel Azi
• Indian/Schoch.......... Alt, Rel Azi
• Bruin ........... (1977) Alt, Crescent width
  0.5 modified to 0.25 min.
• Ilyas_A........ (1984) Alt, Elong
• Ilyas_B modified Babylonian Lag41-49 min for
  0-40 degrees Latitude
• Ilyas_C........ (1988) Alt, Rel Azi
• RGO/CFCO (1981) Alt10 degrees at sunset,
  Elong12/-
• SAfrican Astro Obs Topocenteric Alt, Rel
  Azi
• Shaukat........ (?)
  Alt3.4, Elong 12.7 Crescent width arcmin
  /1.2)1
• Yallop . (1997/8) Rel Alt, Crescent Width
• This criterion was developed from the Indian and
  Bruin criteria by Yallop (RGO) from 295 published
  moon (non)sightings compiled by Schaefer and
  Doggett. A parameter 'q' is derived from the
  relative geocentric altitude of the moon (ARCV)
  and topocentric crescent width. In the original
  technical note byYallop, q was derived at 'best
  time' (ie sunset moonset lag).
• Criterion q Range Remarks
• A q 0.216 Crescent easily visible (Not
  always)
• B 0.216 q -0.014 Crescent visible under
  perfect conditions
• C - 0.014 q -0.016 Need optical aid to
  find crescent
• D -0.016 q -0.232 Optical aid only

27
Earliest Visibility

• How to verify the earliest visibility claim?
• Some 16-20 hours old moons
• Some 20-24 hours old moons
• Some 24-30 hours old moons
• 2 days old moon

28
Tricky Part Observing the Moon

• The easy part is to understand how the moon works
• The tricky part is how people actually observe it
  from the surface of the earth
• How old a moon has to be before the human eye can
  see it
• If the sky is clear, why will some people see it
  and others will not
• Where it is cloudy or hazy, no one will see it
• We can now predict where it will be seen, and
  when

29
Moon Visibility

• In order to be seen, the moon must be approx. 20
  hours old or more
• 12 degrees away from the sun and
• 10 degrees above the horizon
• (Keep in mind that it will not always be seen,
  and not everywhere even if these conditions are
  met)
• The moon is seen on earth starting at point Y and
  its visibility extends westward in a parabola
• Each month, the moon is observed from a different
  place as the visibility maps show
• Earliest point of observation is not repeated for
  hundreds of years

30
Moon-Sighting Historically

• The ancients had no way of predicting moons
  earliest visibility accurately. So the older
  lunar calendars such as the Chinese, Indian, etc.
  used computational tables to check the actual
  observation of the moon each month

In the Muslim World

• The month was fixed by
• Watching the new moon each month, or
• Official government or Islamic body proclamation
  or
• - Other options (fixed calendars, month
  alternating 29 and 30 days)

31
Moon-Sighting Challenges

• Computational modeling predicts when and where
  the moon will be visible first, but
• If you go by visibility, then you face several
  hurdles 1. Sighting starts from a new point
  each month(This means that in one month Chicago
  may see the Hilal, but people 30 miles east of
  Chicago will not. Does this mean that both
  communities should observe separate Hijri
  calendars even though they are only 30 miles
  apart? This was quite common until the 1950s.)
• The answer is NO
• You need to build a uniform calendar based on
  Shariah and Geodesic rules

32
Every Lunar Month is 29 and 30 Days Long
Ramadan started on Nov. 5 2002 at a different
point on Earth than Shawwal on Dec. 4 2002. This
makes Ramadan 29 days long for the Americas and
30 days long for the rest of the world.
33
Earliest Visibility-Based Lunar Calendars

• Earliest visibility starts from a different
  point on Earth each month, as we see here
• Only W. Africa and the Americas could see Safar
  Moon on 2/28/06. The rest of the world saw it on
  2/29/06
• Visibility separator curve requires adjustments
  for
• political boundaries (Canada with the USA, etc.)
• Extending visibility to areas outside visibility
  separator curve (UK on Morocco, Europe on Saudi
  Arabia, or S. Africa)

34
QUESTION AND ANSWER SESSION
35
PART 3 - Global Islamic Calendar

• Islamic lunar month is no less than 29 and no
  more that 30 days long (Hadith Al-Shahru
  haakadha wa haakadha)
• Locally, the Islamic month starts from sunset
  when the crescent moon is first observed and
  continues until a moon is seen again after 29 or
  30 days
• A consistently west-moving dateline based on the
  moons earliest visibility means
• - Islamic month starts from a different point on
  Earth
• - Every month is 30 days long for some regions
  and 29 days for the rest

36
Modern Astronomical Computations (MoonCalc)

• MoonCalc. formalized various visibility criteria
• A strictly visibility-based criterion has
  several drawbacks
• a. Visibility is local and not global. Towns
  only a few miles apart, even parts of a mega city
  might see moon on two different days.
• b. Atmospheric conditions hinder moons
  visibility
• c. Observers mistakes and illusions
• (Visibility reports collected from 1900-
  contain unreliable claims.
• d. Moon watches arranged in 1990s did not
  produce reliable data.
• e. Many moon observers now compete to break the
  old records.
• There is no scientific test to prove or disprove
  a claimed sighting to be valid (i.e. Nov. 2,
  2005)

37
Global Lunar Calendar Standards

• Muslim astronomical computations for Global Hijri
  calendar
• Abdali (1978) First serious attempt to calculate
  the predicted dates of global lunar visibility.
• Minai (1980-81) Detailed analysis of issues
  involved in global Islamic lunar calendar
• Charles Evans (1960-) Photographic images of the
  earliest visible crescent moons
• Afzal (1986) Proposal for computing a global
  Islamic lunar calendar based on the moons
  visibility around 180E
• Imad (1986) First suggestion to make Makkah the
  starting point of an Islamic date
• Ilyas (1986) suggested Probability of moons
  earliest visibility for tri-zonal and bi-zonal
  Hijri calendars
• Turkish ( )

38
Reference Articles on Moons Visibility

• Ashbrook, J. 1984 Astronomical scrapbook, Sky
  Pub. Co. Cambridge. M.A.
• Bruin, Frans. 1977 The First Visibility of the
  Lunar Crescent, Vistas in Astronomy. V. 21, pp.
  331-358 (1977).
• Caldwell, John A.R. 1999. First Visibility of the
  Lunar Crescent. South African Astronomical
  Observatory.
• Doggett, L. E. 1994 Lunar Crescent Visibility
  ICARUS (v.107 p388-403)
• Dershowitz N. E.M. Reingold 1997 Calendrical
  Calculations. Cambridge University Press, New
  York.
• Fatoohi, Louay J et al. 1998. The Danjon Limit of
  First Visibility of the Lunar Crescent. V. 118.
• Loewinger, Y. 1995. Some Comments on the Article
  of Dr. B.E. Schaefer Q.J.R. Astro Soc.
• Odeh S.M. 1999. Taqweem Nasb al-Khata Fi Tahdeed
  Awail al-Ashhur al-Hijriya.
• Qasum et. al 1997 Ithbat al-Shuhur al-Hilaliyah
  wa mushkilat al-Tawqit al-Islami. Dar al-Taliyah,
  Beirut.
• RGO Astronomical Information Sheets 1987-2005
• Schaefer, Bradley E. 1988. Visibility of the
  Lunar Crescent. Q.J.R. Astro. Soc
• Schaefer, Bradley E. 1991. Length of the Lunar
  Crescent. Q.J.R. Astro Soc.
• Schaefer et. al 1993 Records of young Moon
  sightings Q.J.R. Astr. Soc. (v.34pp.53-56)
• Schaefer, B. E. 1993 Astronomy and the Limits of
  Vision Vistas of Astronomy (v.36,pp. 311-361)
• Schaefer, Bradley E. 1996. Lunar Crescent
  Visibility. Q.J.R. Astro Soc.
• Taqweem min 1409 hatta 1440 1408 Madina al-Malik
  Abd-Aziz lil-Ulum wa al-Taqniya Riyadh

39
Technical Standards for a Lunar Calendar

• The only way to build a workable global Hijri
  calendar is to fix
• A fixed Lunar dateline
• A standard method to calculate the start/end of
  every lunar month at the lunar dateline

Social Standards for a Lunar Calendar

• Compliant with Islamic law
• Predictable and computable
• Easily observed
• Easily verifiable
• Easily understood
• Sensible enough to be followed all over the
  world

40
Lunar Dateline

• Why International Dateline (Solar)?
• Two ships only 50 yards apart on the two sides of
  IDL have different dates
• Why International Lunar Date Line?
• For fixed Hijri dates
• Why ILDL cannot be at Makkah?
• Regions east of Makkah even Taif would have a
  different date
• Islamic date/day (from local sunset)
• Global Islamic date from 180E (ILDL)
• The moon will be visible somewhere around 180E
  but not everywhere the same evening

Proposed Lunar International Dateline
Monday
Sunday
180 E
180 W
International Dateline (Solar)
41
Global Lunar Islamic Calendar

• Saudi dates for 1427-1435 (Moonset after the
  sunset in Makka)

42
Global Lunar Calendar (Based on Visibility Around
180E)
43
ICAN

• Islamic Computational Astronomical Network
  (ICAN)
• Hijri calendars
• Global Prayers schedules
• Global Qibla directions
• Misc.

44
Committee for Crescent Observations Intl (CFCO)

• The Committee for Crescent Observation
  International (CFCO) is now part of ICAN, an
  independent group of experts in the astronomy of
  moons visibility, and lunar Islamic calendar.
  CFCO have been helping the Muslims all over the
  world since 1978 by accurately predicting the
  moons earliest visibility in the USA and other
  regions of the world. We provide the Dual
  solar/lunar dates calendar, and the data to
  observe the crescent moon (Hilal) for any place.
• CFCO helps Muslims fast and celebrate Eidain on
  correct dates
•  
• CFCO experts makes sure that the Ramadan and
  Eidain dates are fixed according to the
  observable Hilal of the Quran and the Sunnah. We
  collect sighting claims from all over the world
  each month, evaluate them by set visibility
  standards, and publish our findings regularly.
•  
• CFCOs criterion is the earliest verifiable
  visibility of the crescent moon somewhere (in
  North America).
• Islamic day/date/month begins from a clearly
  visible crescent moon after sunset on day 29 or
  day 30 of the lunation. If a moon is not seen
  consistently then odd claims do not fulfill
  Shariah requirements of Ghalabat-az-Zann
  (overwhelming probability) for Ramadan and
  Ghalabatal-yaqeen (near certainty) for Eidain.

• How to be part of CFCO?
• Support CFCO

45
Summary of Explanation

• This is about making a calendar you can make
  one using the sun or the moon
• People have used different methods to make either
  calendar for thousands of years
• A lunar calendar works the following way show
  with pictures
• It used to be that you couldnt exactly predict
  when it can be seen, now you can
• Before modern telecommunications, people used to
  observe their lunar calendars in a local fashion,
  and it was not possible to coordinate between
  countries and continents
• Now we have a challenge TO OBSERVE ONE GLOBAL
  LUNAR CALENDAR STANDARD
• This standard must be easily observed, easily
  verifiable, easily understood, and sensible
  enough that it can be followed all over the world
• There are two parts to an Islamic lunar calendar
  how the moon behaves, and how people on the
  ground organize their calendar based on its
  movements
• The movement of the moon can be tracked
  scientifically, and through the use of computers
  we can predict this
• That is the easy part
• The tricky part is how people actually observe it
  on earth
• there is the issue of how old a moon has to be
  before the human eye can see it,
• Where the sky is clear, some people will see it
  and some people will not
• Where it is cloudy, no one will see it
• We can now predict where it will be seen, and
  when
• First big challenge agreeing that we can predict
  when and where the moon is sighted (and this
  should always be verified by eyesight, this is
  not just a computer model)
• Second big challenge making a calendar out of
  this
• Once you have a set of lunar times, to build a
  workable calendar you need
• A standard dateline

46
5 Ways to a Great Presentation

• Communication is very important in todays world.
  What and how we deliver our information can be
  the difference between success and failure. Here
  are few tips that guarantee a great presentation.
• 1. SLOW DOWN Speaking quickly means sacrificing
  clarity and may turn off your listeners. Make
  good eye contact, breath more frequently and
  pause between new ideas.
• 2. ORGANIZE your information Tell your audience
  what youre going to tell them. Discuss your
  ideas. Talking about your ideas help you chose
  appropriate medium.
• 3. RECOGNOZE your limitations You will never
  deliver everything you know. We assimilate only 3
  to 5 points of new information during a
  presentation. Be selective of your information
  based on your audience and their needs.
• 4. PREPARE and PRACTICE Outline your
  information, and practice the sequence within the
  time limits. The words you speak in your head
  sound quite different when you speak them loud.
  Discuss the logic behind your ideas.
• 5. BE Yourself Dont try to be or say what
  someone else wants you to be or hear, regardless
  of the truth. Bring your unique qualities to
  your presentation.

47
QUESTION AND ANSWER SESSION