Moon Sighting- The So Called Calculation vs Actual Sighting Debate

[Pakistani1947]

Moon Sighting or Astronomical Calculation - Dr. Louay Safi

This article is a condensed summary of a scholarly paper entitled "Reading, Sighting, and Calculating
From Moon Sighting to Astronomical Calculation." Please click here to view the full paper]
The Fiqh Council of North Americas ruling in favor of using astronomical calculations for determining
the beginning of the Muslim lunar month provoked a strong response, and the American Muslim
community continues to be divided over this issue. Scholars on the two sides of the divide present
arguments rooted in Islamic traditions, and often support their views by citing the same Quranic and
Prophetic sources, or by referring to statements by early Muslim scholars.

It does not take much for an observer to realize that the division and disagreements are not about the
sources themselves, but about how the sources are read. The division is between scholars who place
emphasis on the apparent meaning of the text and those who emphasize its intended meaning and
purpose.

The arguments for relying on sighting the new crescent as a means to determining the Islamic calendar
confound religious duties with the empirical knowledge and practical skills required to identify the days
on which these religious duties commence. Observing Ramadan and performing Hajj is ibadah (religious
duty), but observing the new crescent after birth to determine the beginning of the lunar month is not.
The latter relate to the human capacity for determining the birth of the new crescent, and it is a function
of the observers physical capacity to identify the new crescent. This capacity varies, needless to say,
with the knowledge of the position of the new crescent in the sky, the sharpness of the eye-sight of the
observer, the access to refined tools, the climatic conditions, etc.

Although some Muslims tried to root the practice of moon sighting, particularly for the month of
Ramadan, in the Quranic and Prophetic injunctions, a closer examination of the Quran shows that it
regards fasting of Ramadan and performing of Hajj as religious obligations, but considers the sun and
moon movements as part of the natural order.

The Prophet, indeed, directed the companions to establishing the first day of Ramadan by sighting the
moon, but then he stated that the reason for his directive was the inability of early Muslim community to
provide accurate calculation. The community, he pointed out, was then illiterate and did not master
reading, writing, or calculation. They had no experienced astronomers who have access to the
knowledge, tools, and facilities to determine with accuracy the beginning of the lunar month.
Consequently, Moon sighting was the only tool available for the early Muslim community.
If the distinction between these two areas of knowledge is confirmed, then the only reason for moon
sighting to be favored over astronomical calculation is when the former is more accurate in determining
the birth of the new crescent than the latter.

Early Muslim scholars agreed, by and large, on Moon sighting as the only acceptable way for
determining the beginning of the new lunar month. However, their consensus was greatly influenced by
the state of the science of astronomy, as well as the lack of direct access by the scattered Muslim
villages and towns to reliable astronomers. The consensus reached by early Muslim jurists on rejecting astronomical methods resulted from the lack
of any clear line of demarcation between astronomy and astrology. Most early Muslim scholars equated
astronomy with magic and fortunetelling.

The basis of the historical consensus on moon sighting has changed. Today, astronomers can calculate
with great precision the date and time of birth of the new moon. Moon sighting, on the other hand, has
become less reliable, as the conditions of the sky and the observers have deteriorated markedly over the
last two centuries. Muslims do not only live in middle latitude regions of mostly clear skyas was the
case in the early years of Islambut also in high latitude regions where the moon can rarely be sighted,
and in areas of high humidity and frequent rain. The sky conditions have worsened in most inhabited
regions.

Observation of the new moon is quite disturbing in countries where Muslims do not employ the service
of qualified observers using advance tools and facilities. Communities in the United States, for instance,
rely on claims by ordinary Muslims with limited experience and astronomical knowledge. Even in
Muslim countries where fairly advanced facilities are available, religious authorities accept the sighting
of laymen with little or no training.

It must be asserted, therefore, that astronomical calculations provide a higher degree of certainty than an
actual Moon sighting. For while astronomical calculation provide a precise date and time of the birth of
the new moon, sighting the Moon produces, even with the use of advanced telescopes, less accurate and
reliable results.

Yet the actual choice is not one in which we are asked to choose between astronomical calculation
and moon sighting. The choice is really between calculations and individual testimonies. For
several centuries, the Hanafi school of fiqh required that every qualified person must go to open fields
outside his village and town to observe the new moon. Other school of fiqh required two qualified
witnesses, in some cases one, to verify the actual sighting of the moon.

Those who insist that Muslims abandon astronomical calculation and rely on individual
testimonies are in actuality asking Muslims to abandon the certainty of reliable knowledge, for the
inconsistency of unverifiable individual reports. Individual reports, every student of fiqh knows,
produce uncertain knowledge (marifah zanniyah). This is amply illustrated by the established records of
Moon sighting testimonies. These testimonies have been exceedingly inconsistent, and have resulted in
numerous contradictions and reversals.

There is an ample evidence to convince anyone who is familiar with both shariah injunctions and
contemporary astronomy that astronomical calculations provide a more reliable and certain approach for
determining the beginning of the Islamic lunar months. The fact that contemporary Muslim scholars are
reluctant to embrace this certainty underscores the challenges facing contemporary Muslim scholarship.
The Fiqh Council of North Americas decision to formally adopt astronomical calculation represents a
major step forward in overcoming historical inertia. Although the decision of the FCNA has not so far
brought about a consensus among North American Muslims, it has set the foundation for the
development of a position that can potentially bring a new consensus in deciding the beginning of
Ramadan and the two Eids for the world-wide Muslim community.

 

[nvra911]

Wah Koi Google kerkay bhee wo forumula nahi nikaal saka? Where is the calculation or the forumula some people brag about so much! Formula kahaan hay yaaro?

I'll take a swing at it - (though my posts hardly get approved here and even when they do, it's like a day later, but anyway)...

You're pretty arrogant to begin with. And it's hard to get the point across to people like you: they just want to argue for the sake of a feel-good factor.

When people are referring to advancement in science, they are talking about advanced learning in the field of astronomy, advancement in astronomical tools like the telescopes and aides like the mirrors placed on the Moon by Apollo missions where we bounce of lasers to get the accurate distance of Moon in millimeters from the Earth.

Through these, we can now predict the movements of other astronomical bodies with great confidence, especially the Moon where we can predict within millimeters the accurate position of the Moon in its orbit at a particular millisecond. This is all that is required to formulate a lunar calender. These tools were not available 1,500 years ago and seeing by eye was the only accurate enough way.

You confusion comes from a place of silliness. You are a man of 21st century but stuck in 7th century methods and refusing to update your ideals. So, for you, 'seeing' the moon every month is required to write a lunar calender, where as through 21st century scientific methods this can all be done without each Muslim needing to climb a tree in their towns and cities and coming back with conflicting sightings.

You want to 'see' the Moon to follow the calender, no matter what scientific methods say. So you will forever be stuck in the 'literal-ness' of the argument, keeping on bickering and never understand.

 

[Pakistani1947]

Moreover these formulas use historical data as stem for the forecasting for instance let say that
In 1989 on the 5th day of July it rained 60 mm in New York
In 1990 on the 5th day of July it rained 75 mm in New York
In 1991 on the 5th day of July it rained 2 mm in New York

Nooray key chumchay! You wrong in saying that "moon sighting is being calculated by using historical data"

Today, astronomers can calculate with great precision the date and time of birth of the new moon. Moon sighting, on the other hand, has become less reliable, as the conditions of the sky and the observers have deteriorated markedly over the last two centuries.

It must be asserted, therefore, that astronomical calculations provide a higher degree of certainty than an actual Moon sighting. For while astronomical calculation provide a precise date and time of the birth of the new moon, sighting the Moon produces, even with the use of advanced telescopes, less accurate and reliable results.

 

[Khalid2008]

It's good dabtable topic and we must seriously give it a thought, despite of so much scientific research why we people are still living back in 1400 years. NASA has developed the formula and based on their algorithm, we must follow it. Like we utilise their all other discoveries & inventions, such as computer, electricity, cars, patrol etc. But, fact of the matter is how do these MOLVIS or Roweit Hilal Committe will fill their tummy. Poor Pakistani nation is spending thousands of hundreds rupees on these molvies and Hilal Committee. I think there is no need for such type of committee. Because......... if there is no dispute on the other 11 Islamic months for moon sighting, why there is a dispute on Eid moon sighting.
I can post a link for another thousands years for moon, like we follow other inventions of West or US.

http://eclipse.gsfc.nasa.gov/phase/phasecat.html

But, who will follow it????.......we want dispute and business on the name of Islam. If we follow this scientific research, who will fill the tummies of Ruweit Hilal Committee and Government????? We want our nation remained fool.........(clap)(clap)(clap)

 

[talkingbird2009]

On a philosophical note:

1. Did people not make errors due to visibility or other factors in starting a month at the time of prophet? Yes they did as evidenced by several hadith.
2. Does it make a difference if Ramdhan starts one day early or late or if Eid day one day early or late ? No, the sancitity or blessings of Ramadhan does not diminish a single bit. As evidenced by Hadith Bukahri Volume 3, Book 31, Number 136: Narrated Abu Bakra: The Prophet said, "The two months of 'Id i.e. Ramadan and Dhul-Hijja, do not decrease (in superiority) .
I.e. even if error is made their blessings do not decrease.
3. Only concern would be for Lailat -ul-Qadr. But that is only for people who blindly think that it is on the 27th of Ramadhan. Whereas overwhelming evidence from Hadith is that Allah wants us to search for it in the Last 10 days. Maybe in one year in in the life of prophet it was 27th, in one 25 th or 23rd and then the prophet said that Allah took the knowledge of when it was from his heart. Aisha (RA) said prophet did not know which night it was. So in reality it makes no difference if an error is made in starting or ending a month.

Currently there are 6 positions of various groups:

1. Local sighting
2. Mecca sighting
3.Global Sighting
4. Local Calculation
5. Mecca calculation
6. Global calculation

There are sub-classes in each.

Sighting: Naked eye ( no use of telescopes) or assisted sighting (use of semi powerful telescopes)
Calculation: Conjuction criterion, degree criterion, Minutes criterion with statistical visibility factors.

In the short run there cannot be a consensus. I believe in a Regional calculation / visibility factor based system, which self corrects based on actual sightings in clear conditions. But my belief does not matter. What matters is agreeing on one standard however flawed it might be and having the Eid and Ramadhan and Hajj with everyone together at once.

Yes, there cannot be any consensus as Moon Sighting is not an exact science like 2+2 =4. In the end it comes to what you are more comfortable with. All 6 groups as pointed by you have their reasons to follow their line of perception. Nevertheless, what i wanted to point out is that you cannot call observation by naked eye ( local sighting ) as less scientific than the Global calculation. Infact I find global calculation more risky to follow. If local robust models are generated including all variables and not just the path or birth of moon. The Sighting of moon /visbility is a gray area and more research is needed.

 

[talkingbird2009]

Nooray key chumchay! You wrong in saying that "moon sighting is being calculated by using historical data"

Today, astronomers can calculate with great precision the date and time of birth of the new moon. Moon sighting, on the other hand, has become less reliable, as the conditions of the sky and the observers have deteriorated markedly over the last two centuries.

It must be asserted, therefore, that astronomical calculations provide a higher degree of certainty than an actual Moon sighting. For while astronomical calculation provide a precise date and time of the birth of the new moon, sighting the Moon produces, even with the use of advanced telescopes, less accurate and reliable results.

Some how you are not getting the essence of the discussion and you are missing the difference between the path, birth and visibility although they are interlinked but does not necessarily mean that if the new moon is there than it should also be in the visible range.

 

[talkingbird2009]

It's good dabtable topic and we must seriously give it a thought, despite of so much scientific research why we people are still living back in 1400 years. NASA has developed the formula and based on their algorithm, we must follow it. Like we utilise their all other discoveries & inventions, such as computer, electricity, cars, patrol etc. But, fact of the matter is how do these MOLVIS or Roweit Hilal Committe will fill their tummy. Poor Pakistani nation is spending thousands of hundreds rupees on these molvies and Hilal Committee. I think there is no need for such type of committee. Because......... if there is no dispute on the other 11 Islamic months for moon sighting, why there is a dispute on Eid moon sighting.
I can post a link for another thousands years for moon, like we follow other inventions of West or US.

http://eclipse.gsfc.nasa.gov/phase/phasecat.html

But, who will follow it????.......we want dispute and business on the name of Islam. If we follow this scientific research, who will fill the tummies of Ruweit Hilal Committee and Government????? We want our nation remained fool.........(clap)(clap)(clap)

Loonytoon this only gives the phases of moon we all know what is a full moon, quarter moon , half moon and cresent... the question here is not to predict moon phases but the visibility of cresent.

 

[talkingbird2009]

I am quoting an excerpt from a similar discussion article on BBC

Project leader Dr Steve Bell, of the HMNAO at the Rutherford Appleton Laboratory in Oxfordshire, says the aim is to find out when the naked eye can spot the new Moon.
"We know exactly where the Moon is in the sky - the question is can we see it with our eyes or with an optical aid?"
The new Moon occurs after sunset within three days of the new lunar month - but the timing depends on the relative positions of the Sun, the Moon and the observer. Data on the Moon's visibility mostly comes from sightings at more southerly latitudes, including the US. But these predictions are not accurate for Europe, hence the project.

 

[talkingbird2009]

Source : http://news.bbc.co.uk/2/hi/uk_news/magazine/4311096.stm

 

[talkingbird2009]

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[TD="colspan: 3"]The mystery of the Moon

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[TD] By Becky McCall
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No-one knows exactly when the new Moon appears as it changes in different parts of the world - particularly important if you want to know when Ramadan starts. So this month, scientists are asking the public to help refine the lunar calendar.
For thousands of years, man has looked to the heavens for spiritual solace. Many religions also rely on celestial bodies to determine the timings of their most important annual festivals.
None more so than the Islamic holy month of Ramadan, which begins with the first sighting of the new crescent Moon. But for years it has been beset with debate over whether this first sighting can be accurately measured - and so for some it began on Tuesday night, for others Wednesday.
Ramadan involves fasting, spiritual contemplation and giving to charity. Its end, 29 or 30 days later when the next new Moon is seen, is the festival of Eid, a time of celebration as people reflect on their faith and lives.
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Easter falls on first Sunday after a full Moon

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Dr Usama Hasan, of the Muslim Council of Britain, says: "I look forward to fasting as a time to get rid of bad habits and concentrate my mind through prayer. As soon as the new Moon becomes visible about 20 minutes after sunset, it signals that fasting begins in the early hours of the next morning.
"The Koran says: 'Begin fasting when you see the new crescent Moon; end fasting when you see it again'. The new Moon only becomes visible when it is the correct distance from the Sun to reflect enough light."
Sky at night
But exactly when this new Moon first appears is the subject of annual controversy - so much so that families split by the continents find themselves divided over when to start the holy month.
While the Ramadan cue in the West tends to come from Muslim nations in the East, in astronomical terms, the moon appears differently around the world.
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Ramadan, already underway elsewhere, starts today in the UK

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Secondly, the very faint new Moon can be hard to spot in the UK and northern Europe because of the weather conditions and light pollution in cities.
Does this matter? For many, no. They follow Islam's holiest site, Mecca in Saudi Arabia. But for others it does.
Dr Khalil Roberts, of the Islamic Astronomical Society, said that some British Muslims have stopped taking the cue from the East.
"Islamic teachings encourage the use of technology to help establish Islamic dates, hence British Muslims feel it is important to reconcile the two and not feel pressured into following inaccurate decisions made in other parts of the world."
This may sound like an arcane theological discussion to some, but it has financial implications. Ramadan, like Christmas for Christians, is a time of holiday. Like any major festival, it affects the economy.
This is where the Moon Watch scientists come in - and the public, whose help they need.
On Wednesday the Institute of Physics (IoP) and HM Nautical Almanac Office (HMNAO) are launching a nationwide study to work out if sightings of the new Moon match predictions. This Einstein Year project coincides with Ramadan, so the team hope Muslims will help supply the data.
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Tropical latitudes, such as those in Saudi Arabia or South East Asia, will see the new crescent Moon earlier than elsewhere

Dr Steve Bell

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Project leader Dr Steve Bell, of the HMNAO at the Rutherford Appleton Laboratory in Oxfordshire, says the aim is to find out when the naked eye can spot the new Moon.
"We know exactly where the Moon is in the sky - the question is can we see it with our eyes or with an optical aid?"
The new Moon occurs after sunset within three days of the new lunar month - but the timing depends on the relative positions of the Sun, the Moon and the observer.
Data on the Moon's visibility mostly comes from sightings at more southerly latitudes, including the US. But these predictions are not accurate for Europe, hence the project.
Wax and wane
As the Moon passes through the lunar month, some 29 and a half days, its visibility varies according to the amount of its surface illuminated by direct sunlight, and where it sits in the sky relative to Earth's position to the Sun. Click here for the phases of the Moon.
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Special dishes are made

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The Moon is not visible at the start of each lunar month. The first sighting is a crescent, which thickens through to first quarter to a full Moon, and then wanes until it can be seen no more.
Models used to predict its location are accepted as accurate - but it's the visibility that is in doubt. In the Tropics, the Moon appears higher than locations further north. The further north the observer, the more likely it is to be low in the sky - and therefore obscured by the twilight.
"Over its 19-year cycle, the Moon ranges from -28.5 degrees to +28.5 degrees in its angle to the Earth's equator," says Dr Bell.
"This has a direct bearing on how easy it is to spot the new crescent Moon. Couple this with the relative positions of the Sun and the Moon, and it can be shown that tropical latitudes, such as those in Saudi Arabia or South East Asia, will see the new crescent Moon earlier than elsewhere."
He hopes that the project will allow scientists to check observations against current predictions, providing information to improve the models where necessary. Those keen to take part can submit their postcode, weather conditions, date, time and orientation of the crescent to the Moon Watch website (see Internet links on right). The team will then incorporate this information into existing astronomical models, which are used to generate dates for the Islamic calendar.
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[hunter123]

This is just like a weather map and is based on position of the moon . I repeat its not the position but the Visibility of the moon that decided the Lunar Calender.

Do you understand the difference between the Position/Path and the Visibility?

The Visibility does depend on the position of the moon but there are other variables involved too.


The Map you pasted above is non conclusive and is analogous to weather Map

I am asking you of the calculation or the formula. Can you Kindly provide us with that?

The question is, does the decision depend on visibility or position of the moon?

If you think that the answer to this question is visibility, then what happens when the visibility is good enough in one city but not in the neighboring city? The two cities will celebrate Eid on two different days.

Now, the city that had good visibility can prove the next day that that the other city was wrong yesterday because the moon will clearly be larger than the expected size of a new moon the next day.

Also, visibility is a vague concept (It depends on your senses and the tools that are available to you). If people in one city have a telescope and the people in the next city do not, then both can make opposite claims regarding visibility and both will be correct. But there could still be two different Eids.

Therefore, in the presence of tools/orbital calculations that can aid in the moon sighting, using any method other than these will result in errors such that sometimes, due to lack of visibility at the start of a month, Islamic calendar may be disturbed when you see a new moon on "28th" of the month.

Therefore, in my humble opinion, we should make all possible effort to decide the moon sighting not only through human vision but all tools at our disposal to determine the start of the new Islamic month accurately.

And Allah knows best.

 

[talkingbird2009]

The question is, does the decision depend on visibility or position of the moon?

If you think that the answer to this question is visibility, then what happens when the visibility is good enough in one city but not in the neighboring city? The two cities will celebrate Eid on two different days.

Now, the city that had good visibility can prove the next day that that the other city was wrong yesterday because the moon will clearly be larger than the expected size of a new moon the next day.

Also, visibility is a vague concept (It depends on your senses and the tools that are available to you). If people in one city have a telescope and the people in the next city do not, then both can make opposite claims regarding visibility and both will be correct. But there could still be two different Eids.

Therefore, in the presence of tools/orbital calculations that can aid in the moon sighting, using any method other than these will result in errors such that sometimes, due to lack of visibility at the start of a month, Islamic calendar may be disturbed when you see a new moon on "28th" of the month.

Therefore, in my humble opinion, we should make all possible effort to decide the moon sighting not only through human vision but all tools at our disposal to determine the start of the new Islamic month accurately.

And Allah knows best.

Good point raised brother. In that case I would say that countries or regions which lie in the same time line and hemispheres should observe eid on sighting of moon in any one of the area. Lets say that Karachi...to taskent same time line . Please see the figure below. The longitudinal lines also called longitudes are called time lines.

 

[talkingbird2009]

Islamic literature speaks of Sighting ( Visibility) of the moon and not the phase or position. This is an open discussion and different approaches to answering the riddle exist

 

[Hadith]

Its not the probability, and its not about the advancement of science only,first thing to understand is that space is more than three dimensions, I am not going to deliver lecture on string theory, or anything, because the thread starter has already put us as half literate and uneducated in science, so will not brag about any of my background. Lets try it simple in mullahs philosophy first sura Nisa, says"Moon, sun, starts(means all heavenly bodies) are in continuous motion on a path fixed for them by god, and they do not have the power to sway away from their path,as its the law of god which is imposed on them and they do not have freedom to disobey' this means that they have been given a set law and they just follow it, while for humans god gave the law and also gave freedom to choose(Insan Azad hay, Allah nay os ko upnee fitrat(mean able to make decisions and choose to change).If all this is true then Moon revolve in set path, and solar system revolves on its path and galaxy revolves on its path and space revolve on its path, which is all fixed by god for set period of time.Thus moon will appear at certain lat&Long in a harmonic way always, no matter its cloudy, sunny or what ever, the cycle goes on, rain does not mean earth has stopped revolving, or moon has changed its path, or solar system has stopped revolving, most SC clouds and CU clouds at 600 to 1000 high, and toposphere extends to about a mile (I think do not recall exact),and above that there are no clouds one can go above clouds and see thats its all clear and sunny.I do not understand what the sighting of moon has to do with probability of Rain? Probability of rain will tell the chances of rain for the specific day not the moon sighting..by your sighting argument, a blind person who never see moon should do what?

 

[hunter123]

Good point raised brother. In that case I would say that countries or regions which lie in the same time line and hemispheres should observe eid on sighting of moon in any one of the area. Lets say that Karachi...to taskent same time line . Please see the figure below. The longitudinal lines also called longitudes are called time lines.

I didn't completely understand what you were trying to say. However, from what I do understand, I agree that Eid day should be decided based on the location (longitude/Latitude). Now, since the orbital mechanics are extremely reliable and well understood* and the position of the moon can be predicted with very high accuracy relative to any point on Earth, in my humble opinion, it is better to shift to a scientific system to predict moon rise at a given location instead of relying on eye sight/binoculars alone.

If we do this, we would be able to reliably predict what Islamic date it will be on any given day in the future. This is a huge deal. No civilization has ever advanced without having its own calendar. If ever there is to be an Islamic civilization again, it must be based on the Islamic calendar (i.e. the Islamic calendar must be used for all trade and book keeping). If the Islamic calendar is to be commonly used, it must be accurate and predictable. Q.E.D.

And Allah knows best.



* Otherwise it would be impossible to land a mission on moon/mars or, for that matter, construct a reliable GPS system

 

[talkingbird2009]

I didn't completely understand what you were trying to say. However, from what I do understand, I agree that Eid day should be decided based on the location (longitude/Latitude). Now, since the orbital mechanics are extremely reliable and well understood* and the position of the moon can be predicted with very high accuracy relative to any point on Earth, in my humble opinion, it is better to shift to a scientific system to predict moon rise at a given location instead of relying on eye sight/binoculars alone.

If we do this, we would be able to reliably predict what Islamic date it will be on any given day in the future. This is a huge deal. No civilization has ever advanced without having its own calendar. If ever there is to be an Islamic civilization again, it must be based on the Islamic calendar (i.e. the Islamic calendar must be used for all trade and book keeping). If the Islamic calendar is to be commonly used, it must be accurate and predictable. Q.E.D.

And Allah knows best.



* Otherwise it would be impossible to land a mission on moon/mars or, for that matter, construct a reliable GPS system

 

[talkingbird2009]

Dear Hunter Sahab, Please check the above time lines that run from north to south!

 

[hunter123]

Dear Hunter Sahab, Please check the above time lines that run from north to south!

Yes I agree, we can use the time lines which are derived from the long/lat system of position measurement. (as I also mentioned in the last post)

There could (would?) still be controversy about how high above the horizon the moon must be before it is classified as visible (5 degrees/10degrees etc.) however, a collective agreement must be reached and adopted. This is very important as I tried to articulate in my previous post.

 

[talkingbird2009]

Yes I agree, we can use the time lines which are derived from the long/lat system of position measurement. (as I also mentioned in the last post)

There could (would?) still be controversy about how high above the horizon the moon must be before it is classified as visible (5 degrees/10degrees etc.) however, a collective agreement must be reached and adopted. This is very important as I tried to articulate in my previous post.

You are right and that ascertain the fact that the current knowledge is not robust and concrete about the sighting of moon. The scientific calculation /forecasting etc etc has many unknowns at the moment. When would the new moon be visible to the human eye and to what extent...from where to where on the time line , this is another question. Good debate and i thank you for your input.

 

[Aleph]

@talkingbird2009:

If you are saying that the position/orbit of the moon around the Earth is based on an aggregation of the previous data then you are actually mistaken. That is just not the case. The movement of 'heavenly bodies' (planetary motion) is determined by observance (yes, sighting determines the calculations!). For example, are you trying to suggest that the Gregorian calendar (viz based on the Earth's orbit around the Sun) is based on predictive calculations? While earlier civilizations kept a track of such previous movements (due to time not being divided as it is today and not knowing with certainly either the mass nor volume of the heavenly bodies), but today we have relatively more accurate data available.

The movement of the Earth around the Sun - and the movement of the moon around the Earth - is a fixed term. There are clear texts from both the Qur'an and Sunnah to support this. For example read the following verse of the Qur'an (and mind you Science agrees with this):

And the Sun runs to its resting place. That is the decree of the Almighty, the All-Knowing. And We have decreed set phases for the Moon, until it ends up looking like an old palm spathe. It is not for the Sun to overtake the Moon nor for the night to outstrip the day; each one is swimming in a sphere. (Surah Ya Sin, 38-40)

Or consider the following hadith of Rasulullah (SAW) where he categorically states number of days it takes for the moon to orbit the Earth is either 29/30 days (fixed):

SAHIH MUSLIM
HADITH_No 2378
Allah's Messenger (peace_be_upon_him) said: Whenever you sight the new moon (of the month of Ramadan) observe fast, and when you sight it (the new moon of Shawwal) break it, and if the sky is cloudy for you, then observe fast for 30 days.

I will grant you that there is a DIFFERENCE between motion/position and visibility/sighting. It is for this reason that I belong to the camp where I say that new months should be based on the SIGHTING as opposed to calculations. Although calculations are accurate, but you rightly point out that its visibility cannot be determined by calculations alone.

For example, the new moon for Shawwal this year was born on the 6th of August, 2013, @ 20:50:42 Universal Time. This would mean that in KSA the time would have been 23:50:42. It is a matter of observable fact that the newly born crescent cannot be seen by the naked eye (or even with a visual aid for that matter) until at least 14 hours of its birth (it's just not physically possible!). So if people want to follow calculations then they are stuck with the following problems:

1- What would you do in the above case (which is actually what has happened last night) where the new moon is born so late in the night?
2- What would you do if the new crescent is born early morning or late afternoon UT?

So I am with you so far as the arguments go for calculation v/s sighting. However, the assertion that the moons orbit is based on predictions is just wrong. You are also comparing oranges to apples by drawing a parallel with rain patterns (which is based on predictive patterns, albeit there is much more complex calculation involved than just predictive patterns alone).

Finally, here is a mathematical formula for calculating the Moon's orbit (its sidereal orbit): http://www.bths.edu/ourpages/auto/2008/12/18/41272821/Calculating the Period _T_ of the Moon.pdf