The Islamic holy month of Ramadan falls at a different time each year because the Islamic calendar is a lunar calendar, based on the moon’s natural cycles. That’s why there isn’t a fixed date for Ramadan, which is the 9th month in this calendar, traditionally determined by the sighting of a crescent moon. Today – May 15, 2018 – is the date of new moon, that is, a moon most directly between the Earth and sun for this month. New moon comes at 11:48 UTC today (12:48 p.m. London Time; 7:48 a.m. Eastern Daylight Time in the U.S; translate UTC to your time). We’ve seen some announcements that Ramadan in 2018 will begin this evening – the evening of May 15. We’ve seen other announcements that the beginning of Ramadan will be announced on May 15.
Will anyone on Earth be able to see the moon on this Tuesday evening with the eye alone? Yes. Possibly. The chances are best for those for those living at longitudes farther and farther west from, say, London. The farther west you are on May 15, the more time will have passed on your clock since the instant of new moon. Thus, because the moon orbits Earth continuously, the moon will have had more time to move away from our line of sight to the sun, on the sky’s dome.
In other words, the farther west you are, the longer after sunset the moon will set. The darker your sky will be. For those reasons, the farther west you are on May 15, the more likely it is you’ll be able to see the young crescent in the western twilight sky after sunset.
Let’s consider the youngest moon that can be seen with the eye alone. By youngest I mean closest to new moon.
A longstanding, though somewhat doubtful, record for youngest moon seen with the eye was held by two British housemaids, said to have seen the moon 14 3/4 hours after new moon, in the year 1916. That story has been around for over 100 years. Is it true? Who knows?
A more reliable record was achieved by well-known writer, photographer, and naturalist Stephen James O’Meara in May 1990. He saw a young crescent with the unaided eye 15 hours and 32 minutes after new moon. Stephen had amazing eyesight when he was younger; he saw a number of noteworthy astronomical sights. Click here to read more about the youngest moons it’s possible to see.
I haven’t heard of anyone besting Stephen’s record, so let’s assume 15 hours and 32 minutes is the record for the youngest moon.
Will it be possible to see a young moon after sunset on May 15 from the Middle East? No. Let’s use Dubai in the United Arab Emirates as an example. Dubai is 4 hours ahead of UTC. New moon is 11:48 UTC (translate to your time) on May 15; so the new moon comes at 15:48 (3:48 p.m.) on Tuesday in Dubai. At sunset that evening (6:56 p.m.), as seen from Dubai, the moon will be only three hours old, invisible in the sun’s glare. And in fact, Dubai is one of the places where it’s been announced that the UAE’s moon-sighting committee will meet on May 15 to decide the start date of Ramadan.
How about London? No. At sunset on May 15, the moon will be a few hours older than it will be at sunset in Dubai, but not old enough to be visible to the eye after sunset.
Let’s keep going west. How about somewhere in North America? Consider Pacific Daylight Time, which is 7 hours behind UTC. New moon happens in Los Angeles, for instance, at 4:48 a.m. Pacific Daylight Time on Tuesday, May 15 (11:48 UTC – 7 = 4:48 a.m.). The sun sets in Los Angeles at 7:48 p.m. on May 15. Thus at sunset on May 15 – as seen from Los Angeles – the moon will be 15 hours old. Remember … 15 hours and 32 minutes is the record youngest moon. That record has been around since 1990. It’s doubtful it’ll be broken from the contiguous U.S. states on May 15 … but presumably it’s possible.
The best place to attempt to catch sight of the young moon on May 15 will be an island in the Pacific Ocean. Honolulu, Hawaii – for example – is 10 hours behind UTC. So new moon happens on May 15 at 1:48 a.m. for Honolulu. The sun sets at 7:03 p.m. on May 15. On that evening, after sunset, the moon will be about 17 hours old and possible to see, though extremely challenging. You would need a very clear sky after sunset, all the way to the western horizon. You would want binoculars to scan along the horizon for the moon; once you spot it, try taking the binoculars away and viewing the moon with the eye alone. I saw an 18-hour moon once. It was buried in deep and bright twilight, very ghostly in appearance. Not sure I would have spotted it if I hadn’t been standing in a high place with perfect viewing conditions, scanning for this slimmest of crescents with binoculars.
As you go west from Hawaii to the International Date Line, the potential for a young moon sighting on May 15 continues to get better. It gets better still when you cross the International Date Line, into, say, Asia. From much of Asia on May 16, the young moon will be possible to see.
And – as Earth spins under the sky, and the moon moves in orbit, putting distance between itself and our line of sight to the sun – the moon will get easier and easier to see. It should most definitely be possible to see the moon from India or the Middle East on May 16, assuming you have excellent sky conditions.
Ramadan, for observant Muslims, is a time of fasting, prayer and charitable giving. Here is a beautiful poem about Ramadan, by Rumi, a 13th-century Persian poet and mystic:
O moon-faced Beloved,
the month of Ramadan has arrived
Cover the table
and open the path of praise.
O fickle busybody,
it’s time to change your ways.
Can you see the one who’s selling the halvah
how long will it be the halvah you desire?
Just a glimpse of the halvah-maker
has made you so sweet even honey says,
“I’ll put myself beneath your feet, like soil;
I’ll worship at your shrine.”
Your chick frets within the egg
with all your eating and choking.
Break out of your shell that your wings may grow.
Let yourself fly.
The lips of the Master are parched
from calling the Beloved.
The sound of your call resounds
through the horn of your empty belly.
Let nothing be inside of you.
Be empty: give your lips to the lips of the reed.
When like a reed you fill with His breath,
then you’ll taste sweetness.
Sweetness is hidden in the Breath
that fills the reed.
Bottom line: The Islamic holy month begins with the sighting of a young crescent moon. Some on islands in the Pacific might accomplish the very challenge observation of seeing the young moon with the eye alone on May 15, 2018, but most will see it on May 16 or even May 17.
Deborah Byrd created the EarthSky radio series in 1991 and founded EarthSky.org in 1994. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. "Being an EarthSky editor is like hosting a big global party for cool nature-lovers," she says.