"It is He Who made the sun a radiance and the moon a light and
determined stages for it so you know the number of years and the
count (of time)."
Yunus - (10:5)
"They ask you about the new crescents. Say! These are means to mark
fixed periods of time for mankind... "
Al Baqara - (2:189)
"Allah the Exalted created moons as they are signs to mark fixed periods of
time for mankind so start fasting by sighting the moon and stop the same by
sighting it too. If the sky is overcast and cloudy (on the 29th day) then you
should complete thirty days."
Hakim, Musannaf Abdur Razzaq
Islam has established a very simple system for tracking time. Islamic
months start at the sighting of the new crescent and are either
of twenty nine days if the next crescent is sighted on the twenty
ninth of the month or thirty days if the next crescent is not sighted.
This simple system of establishing new months can be used without
any elaborate system of time keeping or calculations and therefore
can be used by all communities and in every era.
However, in the present era of global communication and readily
available information on the birth of the astronomical new moon,
some confusion on the start of Islamic months has become prevalent.
The questions raised on the issue can be summarised as follows:
Why can we not use the scientific data to determine the start
of the new month in the same manner in which we use
scientific calculations to determine the time for prayers?
Why does the Islamic month start up to two days after the
birth of the new moon?
Why is the start of a new month in New Zealand often on a
different day from the Middle East (particularly Ramadhan
and the Eidain)?
This paper explores these issues by considering the following:
The Visible Crescent And The Birth Of The New Moon
The main reason for the confusion on the start of the new months
is due to an incorrect assumption that the visible new crescent
(hilal) as used in the Shariah is the same as the new born moon as
determined in astronomy. The reality is that these two are not the
same. Rather the new born moon and the hilal are two different
phases of the moon.
In order to understand the difference between the new born moon
and the visible crescent we need to know the process that causes
the phases of the moon.
"And the moon, we have measured for her mansions (to traverse) till
she returns like the old, (and curved) lower part of a date-stalk. It is
not permitted for the sun to catch-up to the moon, nor can the night
outstrip the day; each swims along in (its own) orbit."
Yasin - (36:39-40)
We see the moon because it reflects the sunlight falling on it towards
the earth. The amount of light that is reflected to the earth varies with
the position of the moon respective to the earth-sun axis. The amount
of light that is reflected from the moon to the earth determines the
phases (or the size and the shape of the moon) as seen from the earth.
Below the phases of the moon are shown.
The Sun-Moon angle is the angle defined by Sun>Earth>Moon with Earth (where
you are) as the angle vertex. As the Sun-Moon angle increases we see more of
the sunlit part of the Moon. Note that if this drawing were to scale, then the
Moon would be half this size and its orbit would be about 22 times larger in
diameter and the Sun would be about 389 times farther away than the Moon!
As seen in the diagram above, the new moon is in between the sun
and the earth. As the new born moon moves around the earth, more
of the sunlight reflecting from the moon falls onto the earth, making
it appear larger (i.e. it waxes) until the moon appears as a full moon.
After this the moon moves towards the sun-earth axis and wanes until
it once more becomes the invisible crescent.
When the moon is close to the earth-moon-sun centreline, very little
light from the moon reflects on the earth and the moon appears either
very small or invisible, as happens towards the end of a lunar month.
Astronomically, the moon is born when the centres of the moon,
sun and the earth all lie in the same plane, with the moon in
between the earth and sun. Because the moon is in between the sun
and the earth at birth, no sunlight reflects from the moon on to the
earth, and for this reason the moon is not visible at birth.
It is possible to accurately calculate the time when this occurs and this
time is published in calendars or available from the Astronomical
almanacs. However this time is not the time of the formation of the
Shariai hilal - i.e. it is not the time when the new moon becomes
Visible Crescent (Hilal)
Hilal comes from the Arabic word halla which means "it manifested
or it appeared". Hence, in the application of rooyah, hilal is the
new crescent when it appears (or becomes visible). The use of the
hilal in the Qur'an, hadith and Islamic jurisprudence refers to the visible
new crescent rather than the astronomical new moon.
Since the moon is continuously moving around the earth, it keeps
moving away from the sun-moon-earth centreline after its birth.
As the moon moves away from this plane, sunlight falling on the moon
starts to reflect towards the earth and when enough light is reflected,
the moon starts to appear as a thin crescent. In understanding the
formation of hilal it is useful to know the term elongation. Elongation
is the angular separation of the moon from the sun-earth axis as shown
Up until elongation of 7 degrees, no sunlight reflected from the
moon comes towards the earth, hence the crescent remains invisible.
The crescent remains invisible from earth even via telescopes for
elongations less than 7.5 degrees.
Elongation needs to be greater than 10.5 degrees for sightings in
favourable conditions although the earliest confirmed naked eye
sighting is at elongation of 9.3 degrees.
The crescent becomes widely visible for elongations greater than
As a general rule, the moon's elongation changes by one degree
every two hours (this is a crude approximation based on linear
trigonometry while in reality actual motion is in three dimensions).
This is the reason new moons are not sighted for up to a day after
birth and consequently Islamic months can start up to two days after
the birth of the new moon.
Sighting On Different Dates In Different Parts Of The World
An intriguing question is: Why is it that often the moon is not
sighted in New Zealand but it is sighted in the Middle East?
The reason can be understood by reflecting on the development of
the new crescent, for example:
If at sunset in NZ, angular separation is 8 degrees, the moon will
not be seen.
Then after 8 hours, angular separation becomes 12 degrees.
Hence, in all places where the sun sets eight hours after sunset in
NZ, the new crescent could be visible.
Therefore, on the same day the new moon may not be seen in NZ,
but it can be seen in Oman (sunset 8 hours after sunset in NZ) and
n NZ the new crescent will be seen the next day.
Since the sun sets first in New Zealand (according to international
date lines), often countries in the West (eg Middle East) see the hilal a
day earlier than countries in the East (eg Australia, New Zealand).
A question that follows is: Why can't we use the sightings of other
regions? Among the reasons for this is the time factor between the
two regions. For example, when Ramadhan is decided in the Middle
East, it is already early morning or even dawn in New Zealand and
hence we cannot possibly declare Ramadhan at that time of the day.
It is perfectly acceptable that solar dates and lunar dates can be different
in different parts of the world, as seen from the narration of Kuraib
That Kurayb, who travelled to Syria encountered the start of Ramadhan
there on a Friday, upon returning to Medina, informed Ibn Abbas that
he had seen the crescent-moon on the night of Friday, and that the
people in Syria, including Muawiyah the governor, had fasted on Friday.
Ibn Abbas replied that they (in Medina) had seen the crescent-moon on
Saturday, and that they would not stop fasting until they either saw it
again, or had completed thirty days. Kurayb asked,"Will you not suffice
with the sighting of Muawiyah?" Ibn Abbas replied, "No, that is how
the Messenger of Allah (pbuh) commanded us."
In light of the astronomical background highlighted above and as
the sky in New Zealand is often covered with clouds ( particularly
along the horizon ), it is often difficult to determine the new moon
by sighting. The problem is compounded by the fact that Muslims
in New Zealand are concentrated in certain regions and we have
very few Muslims living in areas North of Auckland where
probability for sighting the Hilal may be slightly higher. This has
necessitated us to seek information on the sighting from further
afar outside the country. However, as shown astronomically, even
when it is not possible to sight the new moon in New Zealand
(because it is not sightable as yet), it is quite possible to sight it in
another country where the moon sets a little later the same evening.
As we are all aware, New Zealand being among the East most
countries in the world is the first to see the sun. So the sun rises as
well as sets in New Zealand before other countries ( except Fiji) .
By the same token the moon also rises and sets here before the rest
of the world. This means that the rest of the world is likely to see
the new moon before us and we will be the last one to sight it. So,
because of this law of nature and the requirement of Shariah
(according to Fatawah obtained from various Ulema around the
world ), it is important that the countries we seek information from
regarding the sighting of Hilal lie within the same time zone as
New Zealand. This then restrict us to only one country, Fiji Islands.
Fiji is well inhabited by Muslims throughout the main islands, and
more often than not the skies are clear. Fiji does have a proper
Islamic system in place for determination of the new moon, whereby
sighting in any part of the country is quickly reported (and verified)
to Fiji Muslim League Office in Suva. An announcement is also
made for the general public then on the radio in the 8 pm news.
Experience over the years has shown that if astronomically the new
Hilal is expected to be seen ( Imkan-e-Ru'yah), Muslims in Fiji would
spot it. It has also proved the point that being the east-most countries
of the world, New Zealand and Fiji are the last in the world to sight
the new moon. The current system used by the New Zealand Hilal
Committee has offered us a practical solution to a perennial problem
that divides the Muslim Ummah in most countries.
Astronomical calculations establish the time of the birth of new
moon and not the time when the new crescent would be visible.
A new born moon may not be visible for up to 24 hours and hence
the Islamic month can start up to two days after the birth of the
Since the new crescent grows continuously, it may not be seen at
sunset in one part of the world but may be seen some hours later in
another part of the world. This is the reason Islamic months start
on different dates in different parts of the world.
Because of the difficulties in sighting the new crescent in New
Zealand, we have fatawah from various scholars allowing us to
accept sightings from places that have the same time zone as New
Zealand and have established Islamic system for moon sighting.
Since Fiji Islands fulfills both conditions we accept moon sightings
References and Acknowledgements
Mohammad Ilyas; 2000: The Quest for a Unified Islamic