New techniques for moon sighting explained

By Abdul Hakiim Yakof

Borneo Bulletin – TWO working papers on the use of modern technology for the sighting of crescent moon (Hilal) were presented during the Falak Syar’ie parallel session at The Rizqun International Hotel, Gadong yesterday.

The parallel session was part of the 14th Southeast Asia Survey Congress (SEASC) 2017 organised by the Ministry of Development’s Survey Department, in collaboration with the Brunei Institution of Geomatics (BIG), under the auspices of the Asean Federation of Land and Geomatics Survey (AFLAG). Continue reading “New techniques for moon sighting explained”

New Lunar Crescent of Syawal 1437 seen from Brunei

Bandar Seri Begawan – July 05, 2016. A group of members of the Astronomical Society of Brunei Darussalam was at the Agok Hill in Tutong for the moonsighting to observe the new moon of Syawal 1437H. The western sky was partly cloudy especially new the horizon with the sun set behind the clouds on that evening. At about 15 minutes after sunset, at the clouds break, the 24 hour old hilal was firstly visible through telescopes and CCD Camera at around 6.52 pm. Continue reading “New Lunar Crescent of Syawal 1437 seen from Brunei”

Astronomical Data and Sighting of Ramadan New Moon on June 16, 2015

Bandar Seri Begawan – The official new moon sighting date to determine the beginning Ramadan 1436H will be on Tuesday afternoon, June 16. The sightings will be carried out in several vantage hills across the country by government officials from the Ministry of Religious Affairs and Survey Department.

The following is the astronomical calculation of the moon for Bandar Seri Begawan, Brunei, on the day of Syaaban 29,1436H corresponding to June 16, 2015
1. Sun sets at 18:32 (Local Time)
2. The moon sets at 18:18.
At sun sets,
3. The angular seperation of Moon-Sun is 5.31°
4. Moon Azimuth is 288.75°
5. Sun Azimuth is 293.50°
6. Moon age is 29.3 day old or -3.6 hour before conjunction.

The moon's position on June 16, 2015 from Brunei at sun set.
The moon’s position on June 16, 2015 from Brunei at sunset.

In conclusion, the moon is a waning crescent, that is not a New Moon, and not observable as it sets earlier before the Sun goes down. However, the starting date of fasting in Brunei will depend on the official announcement on that evening.

First Sightings of Lunar Crescent 2015-2019 for Brunei Darussalam

First Sightings of Lunar Crescent 2015-2019 for Brunei
First Sightings of Lunar Crescent 2015-2019 for Brunei (Click on the image for a larger version)

The table above provides the dates and concise data to hunt for the youngest possible lunar crescent in this country, which is a very challenging activity.

First sighting of the new crescent moon is used as the basis of various calendars to signal the start of the new month. For instance, Islam requires that the sighting of the the new crescent moon should be made with the naked eye.

Predicting the first sighting of the new crescent moon has been attempted since the time of the Babylonians. These ancient methods relied on the age of the Moon and the time difference between moonset and sunset. More modern methods use the angular separation of the Sun and Moon, the altitude difference between the Sun and Moon, their relative azimuths and the width of the crescent.

Guidelines on using the table.
Guidelines on using the table.

The following table shows the dates of possible first sighting of new moon crescent (in Arabic known as hilal) for Brunei Darussalam. These dates are colour-coded based on the moon altitude and a crude prediction of the new moon sighting can be related as follow:

1. Red that indicates the moon altitude which is less than 2°. A very slim chance of visibility due to low altitude.
2. Orange that signifies the moon altitude between 2° and 5.5°. There is a slim chance of crescent visibility. However visibility might be improved with the use of optical aids and excellent atmospheric conditions.
3. Yellow that the moon is at altitude between 5.5° and 7.5°. There is a good chance that the crescent is visible to the naked eyes under excellent atmospheric conditions.
4. Green that shows the moon’s altitude is more than 7.5°. The lunar crescent is positioned reasonably high above the horizon making it easily visible to the naked eye.

If you manage to sight the crescent on the dates provided, please share your experience and photos via pabd@bruneiastronomy.org

More info: Jadual Kenampakan Pertama Anak Bulan Di Negara Brunei Darussalam 2000 – 2099

 

 

2011 Aug 30 Brunei Sight Syawal Cresent 1432

Bandar Seri Begawan – The astronomical Society of Brunei Darussalam (PABD) carried out the moon crescent observation at Agok Hill in the afternoon. The weather was very cloudy and the moon crescent was only observed for a few minutes from 18:55 local time through telescopes, binocular and naked eyes.

The 31-hour-old new moon crescent visible through a telescope at 18:55 local time from Bukit Agok, August 30, 2011.
The 31-hour-old new moon crescent visible through a telescope at 18:55 local time from Bukit Agok, August 30, 2011.
A few minutes before the sunset. The weather condition was partly cloudy.
A few minutes before the sunset. The weather condition was partly cloudy.

Present at the observation were Pengiran Shahdani (Vice President II), Awang Hj Mohamad Azri (Exco) and 4 other members.

The result of the observation was submitted to Islamic Crescents’ Observation Project (ICOP). See worldwide observation result here.

Assigned vantage points throughout the country could sight the new moon of Syawal 1432 H. The official announcement of the sighting was also made on TV and Radio and Brunei Darussalam starts Aidilfitri tommorrow, 31 August 2011.