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How do I find the date of next crescent moon on Wolframalpha or any other site which tells the appearance date time of next crescent on a specific location?

I am searching for it to look for 1st of Ramadan.

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2 Answers 2

up vote 4 down vote accepted

Well, in the short-term I can tell you it's a new moon tomorrow (July 30) and a very thin 2% crescent on July 31.

Otherwise, there are tons of websites out there that a quick Google search reveals. Looks like both StarDate and Moon Connection let you select the month and year and will show you a calendar for that month.

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There may be a very specific, religious definition of "crescent moon" in this context. LifeH2O, does the Islamic calendar consider a crescent moon simply the Moon as seen the day after a new moon? If so, then this answer is definitive. – Andrew Jul 29 '11 at 17:18
Good point, Andrew. Though scientifically speaking, unless you are at the exact moment of deepest totality during a solar eclipse, the moon can never be fully new, there will always be the slightest bit of a crescent. Checking Starry Night Pro, it looks like tomorrow at about 12:40PM MDT (I think we're -7 GMT, so 7:40PM GMT) is the moment of the New Moon. – Stuart Robbins Jul 29 '11 at 18:42
In Islamic calendar 1st of moon month starts when crescent of moon appears. Ramazan (month of fasting) is special one and gets more attention. New moon (30th july will not be visible, no crescent can be seen) will not count, instead first appearance of crescent moon starts new month. – LifeH2O Jul 29 '11 at 19:04
Out of curiosity, how does the calendar define the "first appearance of crescent moon"? Practically speaking, I have trouble finding the moon until it's around 3-4%, but I know some who can find it at 1%. – Stuart Robbins Jul 29 '11 at 20:52
Strictly speaking, the first of the month is not to be predicted but is based on the actual sighting of the new Moon, either locally or at some conventional place likely to be clear such as Mecca. – Pete Jackson Jul 29 '11 at 21:29

If you go to Wolfram Alpha and type in

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You get some very helpful information - the exact date and time of the next new moon (in the local time zone), as well as the moon rise and set times. Doing that right now, I get the following:

enter image description here

You can decide if that is the information you need to compute the first day of Ramadan - but you can see here that if the new moon happens at 5:08 pm, and the moon sets at 6:57 pm, you could see a tiny sliver. If you wait a day, you will see another 2% or so.

I do not know the exact definition of the lunar months - but it seems WA is able to answer your query quite nicely. Which was your original question...

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