Why is Hilal Confusing?

What is a Hilal?

Hilal, an Arabic term, refers to the bright waxing crescent when it becomes visible to a normal observer by naked-eye.

What is a New Moon?

The New Moon is a modern astronomical term. It refers to the completely invisible moon at the start of a synodic cycle (29 days 12 hours, 42 minutes and 2.8 seconds).

Often Muslim and non-Muslim experts alike confuse astronomical “New Moon” (completely invisible at conjunction) for “Hilal”. During the time of the Messenger (S) Arabic language had only “Qamar” (Moon), and Hilal (Visible crescent moon) terms. It had no word for the astronomical New Moon (now translated as al-Qamar al-Mawlid (Born moon)) although the Jews in Medina used the Hebrew Calendar based on the “Conjunction at Jerusalem” criterion with some modifications.

Why the Islamic month cannot start from the New Moon?

Since the time of the Messenger (S) Islamic lunar month began from the sunset after a moon was clearly visible to observers with normal vision.

Please keep in mind that there was no printed calendar, not even a set calendar in early Islam. The Messenger (S) could easily adopt the Jewish lunar calendar in Medina, as he did for many other traditions like the fast on the tenth day of Muharram. Instead the Quran instructed the Muslims to fix the time by the ‘visible’ moon.

The Messenger (S) established the tradition of visual moon watch on the 29^th day. If it was not seen then asked Muslim to complete the lunar month to 30 days. It was an established fact that a moon would always be visible on 30^th evening. If it was seen on 28 the or not seen on the 30^th evening then the start of the lunar month was wrong.

Muslim start their month from the sunset after a waxing crescent moon is clearly visible on the 29^th or 30^th day. It is not the black disk, a few shining dots, or broken crescent that experienced moon-watchers track through powerful telescopes and binoculars. In other words, a moon visible only through telescope and binoculars, but not to the casual observers by naked-eye IS NOT the Hilal that signals the beginning of the month.

Visibility Criteria

Determining the earliest lunar visibility is not an exact science. During the last 2500 years, makers of lunar calendars established certain guidelines. (See www.islamicmoon.com).

After years of evaluating earliest visibility claims CFCO experts have determined that Yallop’s “moon’s altitude at 10 degrees at sunset” when its angle is 12 degrees (slightly modified for lower altitude when angle is 12+) as the most reliable indicator of moon’s ‘universal’ visibility.

Fourteen centuries ago when there were no set calendars, the Prophet asked Muslims to carefully look for the Sha’ban moon to be sure about the beginning of Ramadan month Ibn Abbas asked Kuraib to fast 31^st day as the moon was not visible in Medina, though it was seen in Syria 30 days ago. The Sahaba and Muslim Fuqaha adjusted their own numbers of witnesses to be sure that the Islamic dates begin accurately. The required number of witnesses jumped from one or two to a large number. Imam Abu Yusuf, Qadi of Baghdad, required 50 witnesses; Imam Muhammad required couple of witnesses from every mosque in town; others raised the number to 500 for a large town like Balkh.

Muslim Expert

Some expert moon-watchers, like Jim Stamm were able to track the moon at lesser elongation but these exceptional earliest visibility claims fail ‘repeatability’ and universality tests. Other observers at the same location or at other locations farther west but within the visibility parabola were unable to see it.

A good example is Nov. 2, 2005 lunation. North America was outside the most liberal “telescopic” visibility zone. Only one out of a team of ten experienced watchers claimed seeing the crescent moon while others from the same location and through the same telescope could not see any. Another claim of naked-eye sighting extending over ten minutes came from the same area by a casual Muslim observer. Others with him did not see anything. The crescent moon that these two claimed to have seen on Nov. 2 in N. America was not visible in northern parts of India and Pakistan on Nov. 3 some 12 hours later. The moon’s age exceeded 35 hours and its angle was 15+ degrees. The moon was not visible because its altitude at sunset was only 8-9 degrees.

Experienced professional moon-watchers may SEE a crescent moon at a little lower visibility threshold after meticulous preparation when the horizon is exceptionally clear. A good example was Sha’ban 1426 (Sep. 2005) moon from Arizona:

 Sunset (at sea level)   = 18:49                          Moonset (at sea level)      = 19:30
Age at  18:39 pm           = 31 hr. 50 min.        Moon lag time                     = 41 minutes
Relative Altitude           = 8.45 degrees          Elongation from sun         = 13.77degrees
Crescent width               = 26 arcseconds       Illumination                         = 1.44  percent

Experienced professional moon-watchers may SEE a crescent moon at a little lower visibility threshold after meticulous preparation when the horizon is exceptionally clear. A good example was Sha’ban 1426 (Sep. 2005) moon from Arizona:

Sunset (at sea level) = 18:49                       Moonset (at sea level)  = 19:30
Age at  18:39 pm       = 31 hr. 50 min.      Moon lag time                 = 41 minutes
Relative Altitude      = 8.45 degrees         Elongation from sun    = 13.77degrees
Crescent width          = 26 arcseconds      Illumination                     = 1.44  percent