The Odeh Criteria, developed by Dr. Shawkat Odeh after analyzing over 730 historical moon sighting observations spanning more than 150 years, uses two key parameters—crescent width (corrected for lunar distance) and moon altitude above the horizon at sunset—to predict whether a lunar crescent can be seen by the naked eye. This scientific approach addresses the fundamental challenge that while astronomical calculations can precisely determine the moon's position and illumination, actual visibility depends on atmospheric conditions like dust, humidity, and temperature gradients that cannot be predicted with certainty. The criteria distinguish between the astronomical existence of the crescent and its perceptibility to human eyes, providing a framework that bridges faith and science for determining Islamic calendar months.
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ISNET Podcast, Season 3 & Episode 1 | Dr. Shawkat Odeh (IAC) & Mr. Ghulam Mustafa Leghari (SUPARCO)Added:
Rahim asalam allayikum.
Welcome to the first episode of Isnet's podcast season 3. Today we will have a conversation that sits at the intersection of faith, science and one of the most discussed questions in the Muslim world. When exactly does the crescent appear and how do we know for certain? Every year as Hutch approaches, millions of Muslims around the globe wait for the silver of light that marks the beginning of Zilhut. And yet, despite centuries of tradition and decades of modern astronomy, the question of moon sighting continues to spark debate, divide communities, and challenge scholars. Today we are privileged to have with us Dr. Shaka today, one of the world's foremost authorities on Islamic race and visibility, founder of the international astronomical center and creator of the globally recognized OD criteria, a scientific framework used by Muslim communities and Islamic bodies across the world. Dr. Rud, your work has truly been a gift to the SMA and we are deeply honored to have you with us today.
>> Alhamdulillah. Thank you very much. It's my pleasure being with you and thank you for inviting me for this great episode which I believe inshallah it will be beneficial for the whole um inshallah.
>> Inshallah and we are also joined by Mr. Mulam Mustafa Morta Lagari a space science expert at Subarco Pakistan's national space agency. Mr. Dr. Lagari brings a practitioner's eye to this conversation and I know he has come with genuine curiosity and a few questions of his own that we will get to along the way.
>> Thank you Mr. Wam Morta Zalagari.
>> Thank you for having me. Thank you.
>> Thank you. So gentlemen let us begin. Uh Dr. Rud, let us start from the very beginning for our listeners. Moon sighting sounds straightforward. You look at the sky, you see the crescent.
the month begins but uh in reality it it is far more complex. Can you walk us through why cent visibility is scientifically challenging?
>> Yeah, as you said actually lunar crescent sighting should be simple should be straightforward.
Let's not forget this that moon sighting is the requirement to start one of the most important things in our religion uh uh fasting pilgrim.
There are many things which is related to moon sightings. So it's unwise to make such a condition to start these important things in our religion to make it very difficult to make it uh not easy for the people. This is unwise. So definitely there is a problem which we are doing by ourselves.
It's not the nature of the moon sighting itself. It's they are there are some mistakes that we are doing. So if if we look at what's happening in the the Muslim countries actually the reason for this confusion for these mistakes it's related to different reasons there is no single reason but maybe the most important reason for what's happening is because we have many important countries which they are asking the people to look for the crescent and after all there are sites or sites writings for that crescent which contradicts the scientific facts and these countries they are accepting these claims and this is the starting point for the whole problem because we have different countries we have different knowledge among these countries there are persons in charge and officials who know that the crescent cannot be seen on the other hand there are countries which are asking their people to look for the crescent and their eye there are persons who claim seeing this crescent and they accept it. So these countries will start because simply they received the person who claimed seeing the crescent for so for this country this person is accepted that that country will start the month.
On the other hand there are other countries which know that the crescent cannot be seen on that day. So these countries will not accept the sighting of that country. So this is the starting point. Actually this country will start the months. That country will not stop the man. The normal people they don't know anything because unfortunately one of the reasons also is the lack of the knowledge of Christian sighting among the public. They mostly they know nothing about what's happening. So so they don't understand what's happening.
Why why did X country started the month and Y country didn't start the month? This is the main reason. The other reason also arises from the method of crescent sighting. There are countries which accept sighting the crescent by telescope. Other countries they insist on naked eye observation. So definitely this will make also a difference between the countries. In addition to all that, some countries they insist on a moon sighting from within their local border.
So no sighting will be accepted from outside the country. But other countries they accept that. So all these parameters these three main reasons they are working to together to create that big problem that we are facing. So I believe basically there is or it's not what I believe actually this is a fact from scientific point of view there's no confusion it's very clear it's very accurate but the people who are dealing with these fact the these they are the reason for making this whole trouble >> so the crescent may exist will exist astronomically but whether it can be seen is an entirely different question uh Mr. Lagari I know at superco you work with observational data regularly does this match what you encounter in practice.
Yes, exactly. I think most of the time uh from sc if we see from the scientific perspective that the we can you know nowadays we can calculate the exact position of the moon in the sky its altitude uh you know crystal width or in other words its luminosity and the other orbital parameters of the moon that can be these can be calculated at the mill millc second uh you know with with a millisecond precision. So as far as the the you know the position and the you know the illumination and the height of the moon is concerned >> uh this there is no any uncertaintity.
One thing uh uh you know uh when when when we have uh we we observe from our experience that when we have a moon sighting conditions where the moon can be seen uh with the naked eye easily so we find that okay unless or until we have mons on season we don't have any problem of sighting. Uh on the other hand we see that uh our you know models uh sighting models based on the some historical uh records of uh uh moon sighting over the decades and uh these records are you know collected by many observers uh from all around the world and our you know modern um prediction models are based on these observations actually. So when the crescent is clear or easily visible with naked eye, we see mostly that that there is no problem. But we somehow we find a problem when we have crescent at very low altitude and very thin crescent or or we can say that only few% of uh luminosity is is there and it is coming uh to on on earth. In that case uh what we find that uh it is not due to the astronomical data uh that we are unable to see the crescent with the telescope or with the naked eye but it is due to the local you know atmospheric conditions and uh and the weather conditions and we know that the the weather when we are going to you know make uh some calendar or we are going to predict it uh 10 days ago to 10 10 days earlier or 1 month earlier or years earlier for a for a moon sighting prediction uh we see that uh it is very hard to you know scientifically it is very hard to incorporate the weather condition at that particular day because the weather uh scientifically behave as uh you know very chaotic and non nonlinear phenomena. So we do not know exactly for example in Karachi after 1 year what would be the atmospheric and weather conditions at near the horizon because we always see or observe near the horizon. So it is very difficult to you know predict it. So mostly due to uh in in those cases where the chances are you know very little and the altitude is very low although the visibility models predicted that it can be seen when we have very favorable weather conditions but most of the time we see that uh due to our you know dust and hair and we have uh in our you know coastal areas in Pakistan particularly where we have a longer duration of uh moon sighting.
there we observed a lot of haze during uh haze and the humidity during the summer times. So in in those times it's it's I we can say that it's a little bit difficult to you know observe. So there is no issue in the prediction actually but the question is where is the observer actually the observer is standing on the earth and the light has to pass through from the horizon and uh to reach to your observatory or the observer eyes and this is the optically scientifically this this optical path is the longer one and in in in addition when you have hairs and dust and uh high humidity or temperature gradient then it become very little bit difficult for for an observer to observe such kind of a very thin moon. So so so it it is not the fault of uh prediction actually >> it is the uh we can say some nonlinear phenomena causing or diminishing the in incoming light of uh of the crystal moon. So that that that that is the issue actually.
>> Okay. So what we are hearing is that the tracent is not simply a matter of the moon being there. It is about whether human eyes under real sky conditions can actually perceive it. A distinction that is both scientific and deeply practical.
Uh let us now talk about how science has tried to bring certaintity to this uncertaintity. Uh Dr. After you de developed the OD criteria after analyzing hundreds of crescent sighting observations from around the world what were the key variables you identified things like the moon's age elongation and how do they interact to determine whether a crescent can actually be seen by the naked eye?
Uh well actually what we usually do to know whether a crescent can be seen or not. We start by what we call them the three main parameters which is the sunset time, moonset time and conjunction time. Conjunction to make it easy conjunction means new moon. It's the start where it's the moment where the month starts by the waning phase. We don't have a crescent. So, so the there is a big difference between new moon and the crescent moon. Actually, we we we we we have noticed that there is a confusion between the people. They think that the conjunction is the moment where the crescent where the moon is a crescent. This is incorrect. Actually, conjunction is the Wayne phase. It's opposite to the full moon. The there is no brightness. There is no illumination on the disc on of the moon. The the illumination is zero. So this is the conjunction. The crescent is a phase after this waning phase. So as we have the first quarter, we have full moon, we have a crescent, we have also waning phase. So conjunction is the zero point is the waning phase. Nothing is illuminated on the moon desk. So basically we calculate these three parameters. moonset, sunset and conjunction.
So two conditions must met in order to start thinking about crescent visibility. The first condition the moon must set after the sunset because we will look for the crescent after the sunset. So the mo the moon must be there in the sky after the sunset. So if by if by calculations we find that the moon will sit before the sun. So we simply we don't continue and we simply say there is no need for moon sighting because simply the moon set before the sun. So this is condition number one. Condition number two the conjunction moment itself it should happen also before sunset because we will look for the crescent after sunset and we want to see the crescent. So if the waning phase itself didn't happen before sunset there is so there is no point to go out and to look for the curs. By the way, these two conditions might not be important for you in Pakistan because usually usually you do not suffer from these two conditions.
But in other countries, especially in our region, we do suffer from these two conditions because sometimes the moon sets before the sun. Nevertheless, we find official ann announcements from the countries asking the people to go out and to look for the crescent while we know that there is no moon in the sky after sunset. You don't have this in Pakistan.
I have been following you for more than maybe 25 years. You're doing good in in moon sighting. You don't have this problem, but we have it in our countries. So the the the the worst thing happening even though the moon will set before the sun, we have official announcements from the government to look for the people to go out and look for the crescent claims in these conditions. Luckily, starting from 200 2008, luckily starting from 2008, we no longer have these cases in our major countries, Arabic countries like Saudi, Egypt, we no longer have these problems. So things started to be better starting from 2008.
However, there are some countries especially in Africa, some of them are your neighbors. They accept sighting of the crescent while the moon is not in the sky. So, okay, this is phase number one. I have by calculation to to make sure that the moon will set after the sun. I have to make sure that conjunction will happen before the sunset. Are these two conditions enough?
The answer is no. So, this is the reason why we have what we call them crescent criteria.
Not every moon sets after this can be seen. There are some conditions which should be fulfilled in order to say that this crescent have enough light so that I can see it whether by telescope or not naked eye is not the point. So what are these two conditions or what are the conditions? We found out by research by papers the published papers we found out that we found out out that one parameter is not enough to give an accurate judgment for the crescent visibility. So I cannot say if the age of the moon is more than 12 hours then it can be seen. This is not not enough. I cannot say if the moon will stay in the sky for about 30 minutes after sunset the crescent will be seen. This is not enough. Even the angular separation between the moon and the sun and the sky what we call it elongation is this is simply elongation is the angular separation between the moon and the sun. This is the most important one by the way. Even this single parameter is not enough to say sometimes the moon has an elongation of 10° from the sun. Nevertheless, it cannot be seen. In other occasions, the elongation can be let's say 8° and it can be seen. So the elongation alone is not enough. So we found out that we have to have another second parameter and these two two parameters will work together. We found out that elongation between moon and sun and the altitude of the moon above the horizon. These two parameters we found them very accurate to give us good uh predictions for the crescent visibility.
So these are the two par mainly these are the two parameters where the criteria are based for my criteria or the criteria it's based on elongation but to be more accurate actually I don't rely exactly in on elongation the my first parameter is the crescent width how wide is is the crescent by the way it's a linear correlation there is a linear correlation between elongation and width but There is another small parameter which plays a role which is the distance between the moon and the earth.
We know that the distance between moon and earth is not constant.
Sometimes the moon is at per g. It's near the earth. So the crescent moon will be larger. Sometimes it's at uh apogee. It will be far from earth. So for the same elongation sometimes the moon is near so it's big. Sometimes it's far so it's wide. So to be more accurate I don't use elongation. I directly use the width of the crescent. So this is the first parameter. The second parameter is the altitude. The altitude of the moon above the horizon at sunset.
I used two these two parameters. How I could reach my criteria? Simply as you said we have a large database of real observations for the crescent for more than 150 years. There are more than 730 observations. So simply we look into these two parameters for all this backlog and this archive. We look at that observation on that day that observer did he see the crescent or didn't or he couldn't see the crescent if it was positive and he was able to see the crescent we look at the width and the altitude.
So after combining all this database, we we could reach a an accurate judgment that if the elongation is that much and the altitude is that much based on the history and our archive then that crescent can be seen. Similarly that small crescent cannot be seen. So it's simply an archive of hundreds of observations. We studied them and we compared the our two parameters for what really happened. Based on that we can in the future predict whether the present can be seen or not because we already have hundreds of records which can let us predict accurately in future for the crescent whether it will be seen or not.
>> Thank you Dr. >> M. Mr. Lagardi.
>> Yes. Um, thank you very much. I think I firstly I have really appreciate the work of Mr. Mand and his paper is really really remarkable and one of the highly cited paper. I have gone through it many times. We are also using the UDI criteria in Subuparco as well. uh but uh by taking the advantage of uh his presence here. So I want to ask uh especially uh this is little bit scientific that uh you know there are two famous models.
One is yellow and od models and uh uh at the boundary of uh we have a b c and d region in uh od model but at the boundary of uh region c uh we have uh we we have seen that uh you have set the elong minimum elongation criteria let's imagine we have a you know moon sitting at the paraj distance And uh we are assuming that can we see that crescent sitting at parige at very minimum elongation that you reported and it is around 6.4 degree and the classical dungeon limit is around 7° and you know the yellow also add one more degree uh as a horizontal parallax of the moon. So there they are different modern models but they have a different cutff for the dungeon limit.
So how do you see firstly how do you see that affects the you know real prediction. However you have uh you know uh reported in your paper that there is a one observation uh uh and uh that elongation you reported is around 6.4 before but uh do you have any other observation on uh you know in on the ICOP uh website or database that is close to that uh you know 6.4 for degree. Another secondly I want to ask how do you you know compare your model with the yellow model and the shuffle model. Thank you.
>> Well you ask several important questions. It's not one question. There are three questions. So let let me start by the elongation question. Actually uh I do not base my criteria on the elongation. I think uh you are referring I cannot exactly remember because my paper was written 20 years ago. I remember it was published in 2005. So we are talking about something I wrote 21 year years ago. So I must not remember every word but uh I think you are referring to a paragraph in which I mentioned the the world record observation.
So I mentioned that the shortest elongation in our database was 6.4.
Nevertheless, the criteria itself it's not based on that elongation. So definitely in other months it might predict positive cent visibility while the elongation is less than 6.4. So neither myself nor yallop are uh building our criteria in on the elongation itself. It's just an information. I mentioned that in our data basease the minimum elongation was so and so. The minimum lag time which is difference between moonset and sunset was so and so. The shortest age was so and so but but this does not mean the crescent cannot be seen below these values because simply the criteria is not built on these factors directly. As I said earlier, it's a combination between the width of the crescent, which we can consider it elongation somehow, but it's corrected for the lunar distance and the altitude of the moon.
So this is the answer for your for the first question about dungeon limit.
Actually what Dan mentioned in 1930s about 100 years ago is a a conclusion that he reached on that time based on on the observations he had at that time. So after dungeon we have records for more than more than 100 years. So so definitely dungeon limit is no longer valid. By the way, still I can see that many astronomers are giving more important to that parameter than it really deserves. It's just a conclusion as a researcher reached more than 100 years ago based on observations which were available for him at that time. But now we have hundreds of observations after him from which we can conclude that the limit which we call it now dungeon can go well below the 7°. So we have many observations for 6.4 between 6.4 for and we by the way after I released my criteria and based on the observations which we have after 2005 let's not forget that my criteria was released in 2005 and now we are in 2026 so we have 21 years of additional observations so if you will ask me did I find during this 21 years observations which broke audit criteria the answer is yes by the way I I think there's a total I don't know the exact number but I think we have maybe 10 observations during this 21 21 years which broke the audit criteria but the all all these observations were at the border of audit criteria which is already uh expected we all know that the border of any criteria is not very sharp We know that there is some uncertaintity where it can shift a little bit to the east little bit to the west based on the atmospheric conditions which you deeply explained before a while. So because of this we already know when we publish our criteria we already know the the borders are not sharp and there are some tolerance and all these 21 observation all these observations which I estimate them by maybe 10 obser observations were within this tolerance. they were not far observations to the extent that I say okay let me publish another paper with modify all the criteria I don't believe it deserves that all of them they were at the border so so this is answering about the dungeon limit so if we go by the way the dungeon limit there was a doubt for Dan himself in his paper his doubt was he he wrote this in his paper in 19th 30s he said Dan my limit Don's limit is because the atmosphere does not allow the light of the moon to reach us on earth on the ground because of the atmosphere the atmosphere because of the turbulence the scattering of the light we will no longer receive anything if the elongation is less than seven but we know now this is totally incorrect because by using observation ations for the lunar by astronomy by astro imaging either by CCD or Simos. We know that we can go well below dungeon limit. We we we know that we we have pictures and photos for the moon or the lunar for the crescent to be specific for the crescent when the elongation was 3.5. So we know now that that expectation that anticipation in 1930 that the atmosphere will ruin the crescent when it's below when it is below seven. It's not correct. We we we we have now for the crescent when it's about 3.5. Lastly, your last 30 question you asked me about difference between yellow the borders basically and I have said this many times I don't see a real difference between the concept and the origin of and criteria criteria is a recent one which was b by the way based on the same concept of yalop even the equation itself I used the same equation because I believe the equation reached in his paper is good is accurate. I can use it. The only difference between us is I was able to get much more extra observations that he couldn't obtain because yall he published his paper in 1997.
So he based a his criteria based on the observations which were available for him in 1996 when I published my paper. I published my paper in 2005. So there the there is a difference of eight years between us and during this eight years I was able to obtain many important observations for the crescent especially by telescope and if you if you clearly examine the two criteria you will not find a real difference in predicting digitality by naked eye but you will find a huge difference in predicting the visibility by telescope because we already even in 1990s and before that We already have a good and large database for observing the Christian by naked eye. So nothing new will happen after 1995. We already have hundreds of observations by naked eye.
But we didn't have at that time enough observation by telescope because the telescope was not available for all the observers in that time. At that time in 1990 1995 1990 it was not an easy thing to get and bought telescope by the ordinary person they were expensive they were difficult to obtain difficult to buy. So at that time we don't have many observers for the crescent by telescope.
Consequently we don't have enough database for observing the cert the crescent by telescope but after that especially in 2000s no the situation is different we at that time we had observers many observers for the christen by the telescope so we started to get new observations which were not available at that time if my database was available to yalop yalop criteria would have been exactly like a criteria Okay. The only difference between us is because I was able to get new observation which were not available for for Yalop. So I don't say there is a real difference between us. We use the same concept. Everything is almost the same. The only difference is we got new observations which were not available. And this give us accurate prediction for telescopic observation. As I said for naked eye observation everything was clear well before that. Even when I look into YAS criteria which is only for naked eye observation I can say it's somehow accurate although yallop and South African criteria they are more accurate than lastly my criteria which was released in 2005. So I hope I I answered the three question.
>> Yes, thank you for clearing because uh still I I wonder why people are using is still yellow model especially in UK >> as we you know do not have >> uh so many observation. I think it the yellow observations he reported in his paper is around 295 and you reported more than 737 observation in Europe.
>> Exactly.
>> So >> exactly >> but but both of the criteria you know are based on uh you know two parameters arc of vision and the cent width actually.
>> So the our whole whole visibility you know prediction is depends on these two parameters. How do you see uh you know if we try to you know include the algorithm of you know uh meteorology and the human physiology proposed by Schauffer. So can we you know include these uh parameters uh in our uh you know prediction models to you know um predict it much better especially when we have a you know uh piston width is around.1 arcsecond and we at altitude is around five five degree or less than 5°. So in these uh you know scenarios can we uh incorporate um Shaer model uh using his idea behind you know women eye physiology and uh meteorology parameter.
>> Yes actually a great question.
uh I have been dreaming to build uh criteria based on what you have said as you know uh usually we say that we have two kind of criteria it's not one type of criteria the the first one is based on actual observations uh which they call it empirical method the empirical method is to study previous obser observations and to base your criteria on these archival observations they call it empirical method and all the criteria which we have mentioned so far they are from this type of of of method empirical whether it's yalopas South Africa all are empirical on the other hand we have the sometimes they call it theoretical method which follows what you exactly said we will not rely on previous obser observations. Simply we will do calculations.
I will calculate the brightness of the crescent and I will calculate the brightness of the sky behind. Then I will find the ratio between the brightness of the crescent to the brightness of the sky because actually the the challenging parameter inciting the crescent is not the brightness of the moon because the or the the crescent because the crescent is always bright.
The crescent is always bright. Whatever happens, it is always bright. But the difficulty is because this bright crescent, the background of that bright crescent is the sky which is also very bright. So the real problem in a crescent sighting is the contrast.
The contrast is the ratio between the brightness of that bright crescent to the brightness of that bright sky. This is a ratio. The question is, is our eye able to see that crescent at that ratio?
So number one, I have to calculate the brightness of the moon. Number two, I have to calculate the brightness of the sky.
Number three, I have to calculate the limits of my eye. then I can definitely reach a a rigid conclusion whether this crescent can be seen or not based on very accurate calculations. Okay, the wordings I said they are great. Anyone will hear what I have said he will say oh perfect let's go ahead but practically what I have said it's extremely difficult to reach actually I have contacted sheer many times I know shuffer for more than 20 years and maybe five years ago I contacted him because I wanted to start by by the way myself I started doing this maybe 15 years ago I started to to develop my own uh algorithm and I started calculating the brightness of the sky, the brightness of the curtain, the limits of my vision and as you said if you are using a binocular or a telescope then this is not your naked eye. So you have to correct for this. So we have to have some equations which will correct the limit of my eye because when I use a bicular when I use a telescope the limits of my eye is increased. So I have to have some accurate equation which will really tell me what's happening to my eye when I use this telescope of diameter of 50 mm and magnification of 10 x times. I must feed this to the equation. So it so it will tell me okay you are using a telescope.
Wow it's 10 x the magnification is 10 x the diameter of the telescope is 20 cm.
So your vision is increased by so and so. This is not easy to your age. I'm saying the parameters but because all of them by the way are are mentioned in Schiffer's paper shifer's papers because he he has many papers and some of them paper A and the other mentioned in paper B. So your age the the the diameter of your pupil which receives the light is different. As you get older, it gets smaller. So you have to correct this in the equation. The most difficult one is the atmosphere.
You have to correct for the clarity of the atmosphere. How how the atmosphere is clear, the dust, the humidity, light pollution, sorry uh the pollution, the atmospheric pollution will increase the brightness of the sky. When the sky is very clear, we don't see white sky.
We see very pure dark blue sky. But if we have dust, it's no longer blue and dark. It's white and very bright. So dust is increasing the brightness of the sky. On the other hand, the dust is reducing the brightness of the crescent. This is why we hit the dust. When the dust comes when the atmosphere is not clear, two things are happening. The brightness of the background is increasing and the brightness of my object is decreasing.
So do we have this is the answer of your question. Do you have accurate equations which can model all what I have said?
>> No.
>> I tried I tried but as you said the answer I think I think the answer is no. It's a great to reach such mathematical criteria. But do we have the enough enough knowledge?
I think I'm saying I repeated it many times. I think no. We didn't reach this level. So we need to work more in this field. If we are able to reach a mathematical criteria, I would consider this a great achievement. So by the way, we can work together. You have great experts and we have many observations.
So we can work together to reach that one. By the way, one of the podcast >> Yes, we we can give a try at least >> to you know what in my mind that okay not precisely but uh by taking you know uh the averages of uh especially the atmospheric conditions of different location but it's it's a very tedious task. It's a huge task you see.
>> Yeah. By the way, if you go back to Shepherd's paper himself, the maybe the most recent one who investigated in a in a great details in this matter, he's maybe the most famous one in this field.
Even himself if you go back to his paper in which he spoke about this type of criteria and at the end he listed many observations and he tested his criteria against these observations. I think the success percentage I I cannot remember the figure but I remember it was not a great figure. I think it was 60% 70% and something like that. Yes.
>> Yeah. Something like that.
>> Around less than 60%. Yes. Yeah. I think I think something like this.
>> It was around less than Yeah.
>> Yes. So, so, so what I say this it's not a great criteria which is the P success percentage is about 60%. While by the way the the the uh the other type of a criteria, the normal type of a criteria uh the success rate is much higher than this. We assume that the success rate of the mathematical criteria will be more than the uh experimental criteria. But what we find now based on our knowledge now is giving us the opposite expectation. This is why I think we can work together to reach this uh criteria. But as you said, it's a tedious work. It's not something simple to do. It's need it needs good work. But maybe maybe maybe AI can assist us somehow in this field though.
>> Yeah. I always say that moon is there.
It is reality >> but it is actually the weather and we have you know in superco some historical records where where we find that during monsoon season even we couldn't find uh Christian which was easily visible with naked eye. So yes, this happened.
>> By the way, did you see the did you see the crescent yesterday?
>> Yes, we observed uh yesterday and we have some report reportings.
>> Yeah.
>> Uh in the I think in the early early uh just right after sunset some some people observe with the >> So you were able you were able to see it by naked eye also.
>> Yeah, naked eye. By the way, I know this, but I asked you because I was >> Yeah, >> it was at the age of naked eye actually.
>> Yeah. Yeah. Yeah. Why I'm asking you this question?
>> Yeah. Why I'm asking you this question?
We know that when you go to the west, the crescent will get easier to be seen.
So we in UAE, we are to the west of you in Pakistan.
Yesterday you were able to see the crescent by naked eye, right?
Just imagine that we in UAE who were to the west of you and although we were using the astro imaging technology so we know exactly where the crescent and we were able to see the crescent on our screen when we tried to see it not by naked eye uh when we tried to see it by bicular because we had very bad atmospheric conditions yesterday we couldn't see the crescent yesterday by bicular we couldn't see the crescent definitely by naked eye from our from our observatory. Even by telescope is it was challenging even by telescope.
Imagine by the way we were using the same telescope for both for astro imaging and for direct visual because we have a flip mirror. So I can within one second shift between astro imaging and direct observation.
So we were seeing the crescent very clearly on the screen of the computer very clearly. When we switch it visually and we put our eye we were many observers not all of us were able to see the crescent by telescope on the same day in Pakistan where the conditions were little bit >> in UAE you could see it didn't see it this this proves that the atmospheric conditions is a great concern that we really need to worry about we have to do the calculations very accurately however I don't Don't the the audience who are watching us and listening to us now have a feeling that astronomical predictions are not accurate. No no no no no not at all. It's the opposite. What we are saying now the at the the the crescentic criteria they predict the crescent visibility and they will tell you look if the sky is a clear you will see the crescent. What we are talking about now is by the way totally different thing. So I don't want misunderstanding to happen to to to think that what we are saying that visibility criteria are not accurate. No they are they are accurate but what we have been discussing now is that if there are some dust in the atmosphere if the atmospheric conditions are not clear. Okay, we know in advance that if the atmospheric conditions are not clear, then we know that even though the crescent criteria predicts the crescent visibility, but we know that these crescent visibility criteria were based on normal atmospheric condition. What about bad atmospheric conditions? So in advance we know that most probably we will not see the crescent. So what we have been discussing now is can we implement this in the criteria itself where I can tell the criteria look criteria the atmospheric condition today is very bad. Now show me the curves. So it will give me curves then I will tell the criteria look criteria the atmospheric conditions today is normal.
What is the show me the curves look criteria the atmospheric conditions is superb show me the criteria what's happening now we don't have this option we don't have an option to tell the criteria hey criteria the atmospheric condition superb is normal so it it's only one one curve and by the way by the way we know that the beginnings of the curves is the superb atmospheric conditions we know that by the way we have rough estimates We know that if you are at the beginning of the curve, so you must be under a superb atmospheric conditions in order to see the crescent because all the observers who were at the same conditions of the edge or the border of the curve now were able to see the crescent when they had superb atmospheric conditions. If you go a little bit inside the curve a little bit, we know that you should have normal atmospheric conditions. If if you are under very very deep in the cave so no we know that okay it's okay even if you will have bad atmospheric conditions you will be able to see the crystal so it's it's not a matter that we are lost now no even now we can tell in advance whether you need superb atmospheric conditions if you are at the beginning of the curve or you need normal if you are a little bit inside the curve or it's okay if it's very bad conditions if you are inside the curve but what we have been discussing now we don't want to give judgment based on just looking at the curve and by experience I will tell okay okay I know you are at the border at the beginning of the curve so you must have and so no what we are discussing now we need something mathematically done I will enter a figure I will tell him the atmospheric condition is 2 this is called aod the aerosol optical depth it's a value that is measured by devices which tell us how clarity is the atmosphere If it's 0.1 it's superb. If it's 2, it's normal. 3 hazy. 4 bad. These are measurements which we get by small divide handheld device. We point it at the sun. So it will tell me tell me look today the atmospheric clarity which is a o it's 0.1 it's 2. It's 3. It's 4.4 is very bad. By the way it means the sky is full of dust. It's very.5 is terrible.
By the way, yesterday in our observatory it was 0.55.
So it was terrible yesterday. Yeah.
Yeah. At the same time in Iraq there was another observatory who could easily see the crescent yesterday. The value of the AOD is one5.
>> No.
>> And he reported that.
>> Yeah. So just imagine I I have seen.
>> Yeah. Just imagine now by very small handheld device you point it at the sun you will directly get very accurate measurement for your atmospheric conditions and the clarity what we have been discussing now okay let's put this number inside the criteria so it so it will tell me very accurately whether from my location under these atmospheric conditions without having me to be experienced and have I have experience from previous observations.
No, I don't want my previous experience.
No, no, I just want to put a number and it will tell me seen not seen. This is what we have been discussing just in case we don't have any misunderstanding for who's listening to us.
>> Yeah. Thank you.
>> Thank you. Thank you so much Dr. O and Mr. Lagari for this interesting conversation. Now let's move if I may say to rather most sensitive part of this conversation that there are Islamic jurists who argue that uh this astronomical calculation however precise cannot replace the act of physical sighting. They say that calculation alone cannot replace actual sighting uh citing the hadith uh that fast when you see it. So from a scientific standpoint, how do you respond to that? And do you believe science and sighting is in conflict or can they coexist?
Yes, Dr. Od.
Erh well actually if we prepare a calendar in advance based on the criteria which we have been discussing and raising during this whole podcast. So we will have a calendar which will tell me in advance that even if you go out and you observe the observe the crescent your results will be identical to what I have predicted before. So to be honest really I don't really care much about this argument because okay it's a valid one.
Don't forget that this is not a scientific argument it's shar argument.
scholars of Islam should discuss the faukah should discuss this not myself but I can easily say if we and we did reach a high level of accuracy in predicting the crescent visibility so we know in advance that if you want if you as a scholar you insist on actual moon sighting okay I don't mind let's go together by the way let's not forget that we in the international astronomical center we have founded the Islamic crescent of observation project not calculation project. We established the Islamic crescent observation project in 1998.
So we have been observing the crescent for more than 27 years and the results of all these observations are found in our website. Anyone who visit our website astronomycenter.net met he will find the record results of all the lunar month since 1998 to this date. So we are really interested in a crescent sighting. We love the crescent sighting.
We do the crescent sighting. But the question is should we rely on the calculations or the moon sighting? what I'm saying I don't care because I know in advance that if you will follow an accurate prediction or accurate criteria and you say that I will start on Monday 18th of May because I have used the criteria which told me that on 17th of May Sunday 17th of May when I will go out I will be able to see the curs. In advance I have prepared a calendar based in on moon sighting which predicted the beginnings of the month and practically when you will go out your results will be similar to my prediction. So I don't have a real problem. So what I'm saying okay we can go out we can observe but I will tell you in advance both will be similar. The only difference or the only exception when it will be cloudy and this is by the way again issue they they should discuss it not us if it's cloudy and I know that the Christian can be seen will you start a month or not to be honest I don't care I'm astronomer this issue they should decide some I know some scholars they will say no you can start because we know in advance that the Christian can be seen And the hadith said so from point of view I already have hadith which show which which told me I can predict for it. So I will use my prediction. However I know that there another hadith which which said that complete the month 30 days. Okay I have two hadiths. It's up to you to choose whether to complete 30 days or to use our prediction. But what I can tell you if you will use our prediction whether you will go out or you will not go out your results of observation will be identical to my calculations. But what's happening now the reason of the problem is not because of this simply as I started my talk the whole confusion happening the the root cause of our problem is that some countries which is by the way none of them is Pakistan I know Pakistan is doing well in Christian sighting it's other big Muslim countries they ask their people to go out to look for the person then they come back and they claim seeing the curs when all when all the crescent criteria confirm that the crescent cannot be seen. This makes the trouble. So they will accept their claim. They will start the month. But other countries will say no no no I will not start the month. I know your sighting is not correct. I will not accept your sighting. I did my sighting.
I didn't see the crystal. This is the real real problem actually.
>> Thank you Dr. Dave for explaining it. So aptly u Mr. Lavari do you have any remarks on it further? Yes. Uh I think as far as uh the only calculations are concerned and we also uh developed uh we have developed uh many calendars in the past and now we have new calendar and it is also based on you know totally based on the calculations.
uh the decision you know there are uh some countries some Muslim countries like uh Turkey and uh Malaysia, Indonesia and Singapore, Brunai they have famous uh calendar there. So they uh I'm not sure about Malaysia but I'm very pretty sure about Turkey they only follow their calculated calendar and they it has some minimum they have set some minimum criteria to site the moon and on on the basis of that criteria I don't see any error for example we cannot uh if Turkey is announcing uh you know first of any month you cannot have a crescent condition same condition on the 28th of any month conditions will always be you know fulfilled uh only on 29th of the month or 30th of the month so that's the one thing in Pakistan uh we see that we have a you know uh prediction and validation system we have a legislative body that is uh royatal committee of Pakistan and in that body we the the mixture of uh religious scholars and other people uh from the scientific institutions and there are you know three scientific institutions are permanent member of central retail committee. one of them uh is superco also and we provide them you know predicted data in advance uh when whenever they have uh you know sitting on 29th of every month. So what we observe from uh you know their recent you know we we are observing closely most of uh their decisions are perfectly with our predictions until or unless we have a bad weather or we have a you know some kind of uh moon conditions very near to the horizon and uh near to the horizon again it's on the above sky at the zenith you have clear weather condition But near the horizon you have we have already discussed what kind of conditions we faced. In this in that scenario we you know uh our prediction uh somehow not failed but failed due to the atmospheric conditions.
So but also there's another advantage we have in this royal committee that any testimonial the validation of that testimony is based on our data provided data. If any testimony or claim goes against the data they don't simply accept it. So here we you know go hand in hand together with no problem and if we say okay there there is a moon and it is easily visible with naked eye and any testimony comes uh and supports the data they welcome it and they simply accept it. So here uh I think we are uh we are in the uh comfort zone and we are go going good as far as this uh you know moon setting issue is concerned.
>> Thank you Mr. Lagari for the explanation and on that note uh let us look at what the future holds because the tools available to us today would have seemed extraordinary even 20 years ago. Dr. Today we live in an age of satellite imaging, AI based atmospheric modeling and real-time global sensors network. So how are these new technologies transforming the crescent visibility prediction and are we closer than ever to a unified reliable global answer?
Well actually this is a little bit sensitive technology because not many officials accept it. We are talking about uh imaging the crescent by astronomical camera is so we know that to start the month either we look for the crescent by our naked eye we go out and we search for the crescent and that's it. uh we can or or we can have binoculars or telescopes both are the same binoculars or telescopes in the same I can use my own binocular or my own telescope and I look for the cris so this is the second method let's not forget that not all countries accept this second method there are some countries which insists on naked eye observations when I was in Pakistan few months ago and I met the official committee. I asked them do you accept optical aid observations in Pakistan. They had some discussion uh in their own language. So I couldn't understand what they were talking but at the end they gave me conclusion that yes we accept optical aid observations or kiss sighting. So it's okay because I had a rumor that Pakistan they do not accept but the answer the official answer I got that you accept optical observation but this is not the case in other countries. I know other Muslim countries they do not accept optical observation and they insist on naked eye observations. Okay, just imagine within this situation now I'm talking about third type of observation where where we use astronomical camera we attach this camera to the telescope this camera takes many images for the crescent sometimes up to 100 sometimes up to 10,000 images it depends sometimes only one single image is enough sometimes no I have to take many many many images sometimes 20 sometimes 14 100 200 1,000 5,000s it depends but the idea is or the concept is I'm using a camera which is taking many frames then I'm feeding these frames to a dedicated software so I have camera telescope software and this software is stacking these frames or combining let's say the scientific term is stacking but to make it easy it's mean combining I have one hand 100 images I'm putting them on the top of each other so that I will have one image only in addition the software is a little bit enhancing the contrast then after all that I have the image uh I have to be accurate in my description I'm not saying that it's not a really true crescent no I'm against uh I'm against saying this statement no even Though I'm I'm using a camera telescope dedicated software but I we we shouldn't look into it as I am creating the crescent. No, it is a photo crescent and combining the images unlike what some people think combining the images images meaning or the photos meaning that I'm taking part of the crescent from each frame and then I'm creating no no the full crescent is there on each frame but because of the noise in the image I cannot see it clearly. So when I'm when I combine them all what's happening scientifically simply I'm decreasing the noise around the crescent so it will appear the clearly clearly that's it. So I don't want to make it a horror story. No it's not like I'm forming I'm creating I'm drawing. No no it's not like this.
It's the real image of the crescent. I'm taking the real image. I'm just enhancing it a little bit so I would see the crescent. This is on one hand. On the other hand, yes, it's not very direct im sighting of the crescent. It's not only I'm using a telescope. I'm using camera with many frames and software and a computer.
So I'm not with and I'm not against I'm simply explaining the technology. I'm simply saying how it's working. Then the final decision again is for the scholars. It's not it's not for me. I shouldn't be asked as astronomers, you Muhammad, do you believe that such kind of observation is it accepted from Islamic point of of a view or no? No.
It's not me who should answer this question. This question should be answered by scholars by but they must understand this technology before they give fatwa because I know some prominent councils Islamic councils who had a meeting and they discussed this technology and they reached out a fatwa but I'm I'm against that fatwa because simply they didn't understand the tech technology before they give that fatwa the council or the scholar who will the fatwa he must understand what's really happening then he will give a fatwa so basically yes nowadays we have this high-end technology which by the way I didn't mention it but you mentioned that there is AI also which can in a magic way it can detect the faint crescent and it will force the telescope to keep tracking that crescent and it will force the camera to keep taking images for that specific point in the image of the crescent. All this is being done by AI by the way. It was not available 2 years ago. The technology started by the way the astro imaging and imaging the crescent by by camera. This started in 200 2007 I think I think in 2007. But this AI technology which made it much easier by using some AI technologies just started 2 years ago it it it made cent visibility by this technology much much much easier than before. So your question is shouldn't we make use of this technology? Myself I cannot answer. I can simply say the technology I can simply say we have been using it since 2007 till now and we have been criticized many times by many persons saying they saying that this technology is not accepted from Islamic point of view. So simply I answer we are not scholars we are not council we are astronomers. We will observe the crescent by whatever means available. We will even use the calculations also. I'm astronomer. I will do calculations. I will observe the crescent by naked eye.
I will observe the crescent by telescope. I will observe the crescent by camera. Then I will I will publish all that.
>> Then you take from us whatever suits your opinion. Don't force me on your opinion >> because as this is your opinion there are many others who do not agree with you and they they have their own opinion. So it's not my task to adopt a certain opinion and to force all my my work to go in in that direction. No, we do calculation. We observe by naked eye.
We observe by telescope. We observe by camera. We publish all that in our website. Then it's you who will decide which one suits you and you take from us. So yes, the AI has reached to a level to a great level which I cannot even describe. You have to see it by yourself to to just imagine what's happening. So should we make use of this or no? I don't know. Scholars should answer this question.
>> You're right. Yeah. I want to add to this uh you know all of you know from scientific perspective all of our knowledge right now about the universe about these stars and galaxies it's all the observatories we have only two sources one is you know telescope and other is CCT camera so yeah with the I mean if we have a classical era and we see that in classical era We use decade eye behind our telescopes and you know noted down the positions and other things but with the invent of this CCD camera which actually is taking uh something from the heaven which is real and which exists giving us a lot of deep informations about stars and even uh right now we have detected more than uh 6,000 exoplanets.
All of this uh you know could happen with uh with with the invent of more sensitive CCDs imaging. So as far as the CCD imaging is concerned scientifically it is you know it is the image of uh reflection of reality over you know existing above us. So uh but in case of uh you know u one sighting we have you know some point of views from that uh the CCD okay maybe again I don't know whether it is the issue of understanding or not understanding but uh we as Dr. mentioned that yesterday he was you know trying the same uh trying to see the crescent with a naked eye and and the and the telescope naked eye behind the telescope it was not visible but with the CCD it was visible. So we have telescope but no CCD and we have telescope with CCD. You can see the difference that the technology is so much. Even nowadays two years back some company is making AI portable telescopes and they have AI programmed uh we call it AI supported telescope and that AI supported telescopes are far more efficient when we say that you know when we have very uh thin crescent and we want to observe it at very low altitude and we have some favorable weather conditions. So yeah uh I think uh uh in Pakistan we have valid validation and uh you know prediction method uh to make it uh more strong we need to work on more on you know validation system we have when we have a uh conditions like the the cent can only be seen with the telescope we don't have enough observatories and we don't have enough uh you uh observers around the you know across the country. We have to place at least uh more than 100 telescopes at various location of of of the country and we have to train uh you know our staff and you know depute them uh whenever there is a condition that the the the uh Christian can only be seen with the with the telescope. So we have to make strong the the the our validation process. I think by making it strong we will have we will see very different results because the these atmospheric conditions vary so much uh with with you know over we can say 50 kilometers we have different and another 50 km we will have a we have a different atmospheric condition. So at at height in on the mountains we don't have observatories uh enough observatory is there. So we need to place some uh kind of small telescopes over there to you know mitigate the validation issue or to reduce this uncertaintity or filter out uh you know this uncertaintity. There is no uncertaintity actually. it is the uh actually it is the validation process which needs uh so much uh uh enhancement actually in Pakistan.
>> Thank you Mr. Lagari for your detailed uh explanation and remarks. So before we close I want to ask both of you something rather more personal that Hajj is almost upon us. Millions of Muslims are in preparation spiritually, physically, emotionally and uh the day of Arafa, the day of Idul aa these are not abstract calendar questions. They carry the weight of worship and devotion. So what is your message to scholars to governments to space agencies and to the ordinary Muslim looking at the sky about how we pursue certinity under the crescent?
And well actually I think it could be a different message for each entity you mentioned. For example, if I want to convey a message to the scientific and astronomer centers, astronomy centers in the Muslim world, I would uh ask them to pay more attention for the crescent sighting process because actually not all countries they have scientific entity which is observing the crescent every month. So I'm sure that some Muslim countries as a whole country they didn't stud with other Muslim countries simply because they don't have enough number of observers in their country. If there were real groups who were observing the crescent in different parts of the country supported by us telescopes by nuclear definitely they would have been see they would have seen the crescent and they they would have started the month with others even for the hijah though it's a good example because almost almost all Muslim countries have started the month today but there are some exceptions by the way I don't want to mention the name of the countries but there are very very very very very few countries which didn't start the month uh today whether it's correct it was correct because they really couldn't see the crescent or there was a probability to see the crescent but they didn't have enough observers to see to see that curs so this is my first message uh there should be an organized groups equipped with simple by the way I'm not saying no no no I'm talking about very simple bical a small telescope. Uh if this is the case, I'm sure that they will not have problems in some months. Modern number two for the scholars, the officials in in in general, uh they should be cooperation with the astronomers. The case the case is not the same in all the countries. By the way, in our Arab countries, the case was totally different 20 years ago. I was member of official committees at that time. So I remember officials, they didn't pay attention to us at all. But this is not the case now after 20 years but after we have suffered a lot by the way but still in other countries this is the case. So this is a message for the officials that you cannot go alone. You have to work together with science with astronomers with astronomical centers with the space agencies. You should work together. So this is very important because when you work together you will reach the correct knowledge. You will no longer have such disagreements that we we have been encountering for very long time. Final message for the people in general at I believe I believe that we have reached a time where we have to sit together as Muslim countries. We have to reach this an approximate agreement on how to start our month. It's it's unlogic that up to this time we are totally ignoring the science. We are totally ignoring the calendar. We still insist on moon sighting in different approach in different countries. It's not an issue of insisting on moon sighting alone.
It's also the approach is different. The way is different. This country will accept this this sighting from another country. That country will not accept.
This country will accept only local sighting. That one worldwide sighting.
This one will accept naked eye. That one will accept telescope. This one will accept claim of sighting with the moon is not in the sky. So this is this is very bad situation. We have to sit together this for the Muslim countries.
We have to reach at least an approximate agreement. I don't want to reach a rigid great agreement unity 100% at least.
Let's start. But unfortunately we didn't even start in a serious level.
Dr. Ligari he mentioned great example.
We have Turkey and Singapore. By the way, they are the only two countries in Muslim countries in not Muslim country but they have official MUI which is a governmental position. So in a way or another we can consider it as a Muslim system at least these are the two only two countries which start the month based on the calendar and their calendar by the way it's based on moon sighting. So this is very important point when we say that we want to start our months based on calendar this does not mean we will ignore the moon sighting because as we discussed before a while if you will go out and you will do moon sighting you will see there the real results in agreement with our predefined calendar. So isn't it the time that we start relying on pre-calculated calendar which is bathed in moon sighting.
Shouldn't we start gathering, meeting, discussing? Until when we the Muslim countries and we the Muslims we do not tomorrow is read or not read till when I will stay up to 2:00 a.m. I don't know whether after 5 hour I have read prayer or I have Ramadan and I will be fasting after 5 hours. In some countries this is not a problem but in many many countries this is a serious real problem especially for Muslims in Europe and in non-Muslim country. We have we have to reach this agreement. We have to work together. Unfortunately we don't like to work together but we have to work together. We have to find a country which will believe in this concern and it will start organizing uh gathering the people to reach this agreement. At least we should try to start. The real sad fact is we didn't even try to start.
So let's try to start with all the science we know now with all this >> unbelievable AI happening in the world.
We are still relying on naked eye cent moon sighting which we accept testimonies from persons with the moon is not in the sky. This is not Islam.
The first word in Quran is so it's it's unlogic that we we are doing this actually we have to find a solution for this serious problem which cannot be resolved except by countries who will gather the Muslims and will try to find a solution for this issue.
>> Thank you. Thank you Dr. Rod for the beautiful explanation and your message.
Mr. Lavari over to you.
>> Oh, what can I say? I think everything is has already been said by Dr. Rud.
I I can only say that we need realization and uh cooperation and review of this issue. uh and uh I think we can uh reach to some optimal solution and I don't see any contradiction between religion and science and also the religion also we we know that it signifies the very existence of sun moon and the stars and the heavens above so I think uh we need a realization cooperation and review of uh moon sighting issue Thank you.
>> Thank you. Thank you so much Dr. Mohammad Ude and Mr. Wam Mustafa Lagari for very interesting and thoughtful conversation. Uh Dr. has reminded us today that the cryend just that just thin silver of light is not just a celestial event and the tools of science far from being foreign to our faith are in many ways an extension of the Quranic call to observe to reflect and to know Mr. Walam Mustafa your presence today reminded us that this is not only a conversation for scholars and theologians. It is one that space scientists institutions and governments must be part part of. So as we stand on the threshold of Hajj, the season of unity of Arafa, of standing together before Allah, let this conversation be a reminder that we are one um under one moon and with knowledge, sincerity and cooperation, certaintity is indeed within our reach.
On behalf of Interlamic Network on Space Scientist, Sciences and Technology, I once again thank Dr. Shakut and Mr. Bulam Mustafa Lagari for their time, their insight and their commitment to serving this um to our listeners. We pray your Hajj preparations are blessed, your zill is filled with worship and that this Eid, wherever you are in the world, you celebrate with certaintity and with joy.
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