Why Is this Moon Not Visible?
A crescent moon’s first
sighting depends on several interrelated factors. (For details see “Earliest
Visibility Criteria” section.
For a crescent moon to
be visible its age should be around 24 hours, although the youngest sighted moon
was only 14+ hours old. Often moon’s age may be 30+ hours but you cannot see it
because its angle from the sun (elongation) and altitude (above the horizon) do
not reach a minimum (12+10 degrees) visibility threshold.
For a naked-eye sighting
the moon’s angle from the sun at sunset should be approx. 12 degrees.
Moon’s altitude at the
sunset should be 10 degrees or more for a casual observer.
(Higher elongation may
sometimes compensate lower (8+ degrees) altitude.
Moonset After Sunset:
You cannot see a faint
crescent moon within the first ten minutes after the sunset when the time lag
between the moonset and the sunset is less than 42 minutes. Usually a 29 days
old moon will be visible 20-30 minutes after the sunset and a 30 days old moon
will be seen after 10-12 minutes after the sunset.
A crescent moon may
first become visible from as far east as New Zealand or as far north as Japan,
but it may not be seen in Saudi Arabia hours later. Moon’s visibility extends
within a parabola and it takes 48+ hours to cover most of the globe.
Words of Caution:
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) =
Age at 18:39
pm = 31 hr. 50 min. Moon lag time = 41
Altitude = 8.45 degrees Elongation from sun =
width = 26 arcseconds Illumination = 1.44 percent
Casual Muslim Observers:
However, casual Muslim
observers all over the world claim seeing moons that are “Impossible”. Naïve
“experts” and Ulema accept their claim only because they are “Adil”. The results
are disastrous. Eid al-Fitr on the last day of Ramadan, Eid al-Adha on 9thD.
Hijja and Ramadan on 28 Shaban.
If the earliest sighting is not by a large group and not
confirmed from places located west of the first claim the “Shahadah” should be
rejected as doubtful.