Sains Malaysiana 54(9)(2025): 2263-2276

http://doi.org/10.17576/jsm-2025-5409-13

 

The Limitation of Optical Equipment in New Crescent Moon Visibility: Insight from 27 Years of Observation Data in Sarawak, Malaysia

(Had Peralatan Optik dalam Kenampakan Anak Bulan: Pemerhatian daripada Data Cerapan 27 Tahun di Sarawak, Malaysia)

 

AHMAD HARIZ BELY¹, ROSLAN UMAR^1,*, NOR HAZMIN SABRI², AHMAD LUTFI AFIFI MOHD NASIR¹, RAZALIE HUSSAINI³, EMMA ZULAIHA ZULKIFLI^1,4, AMIRUL AKMAL REDZUAN¹, ARWIN JULI RAKHMADI⁵, AMIRUL HAZIM KAMARULZAMAN¹, CHE KU AHMAD FUAD CHE KU ABDULLAH⁶, NUR AZHAR AHMAD⁷, NUR ZULAIKHA MOHD AFANDI¹, SHARIFAH NURUL AISYAH SYED ZAFAR¹, JALALLUDIN BAKAR³
& MUSA GARBA ABDULLAHI⁸

 

¹East Coast Environmental Research Institute (ESERI), Universiti Sultan Zainal Abidin, 21300 Kuala Nerus, Terengganu, Malaysia
²Advanced Nano Materials (ANoMa) Research Group, Faculty of Science and Marine Environment, Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia
³Bahagian Falak, Jabatan Mufti Sarawak, Lorong P. Ramlee 5, KTLD, 93400 Kuching,
Sarawak, Malaysia
⁴Dark Sky Malaysia, Pusat Inkubator Perniagaan, 88000 Kota Kinabalu, Sabah, Malaysia
⁵Observatarium Ilmu Falak, Universitas Muhammadiyah Sumatera Utara, Glugur Darat II, Kec. Medan Tim., Kota Medan, Sumatera Utara 20238, Indonesia
⁶Unit Geomatik, Jabatan Kejuruteraan Awam, Politeknik Kuching, 93050 Kuching, Sarawak, Malaysia
⁷Academy of Contemporary Islamic Studies (ACIS), Universiti Teknologi MARA, 94300 Kota Samarahan,
Sarawak, Malaysia
⁸Department of Physics, Faculty of Science, Yusuf Maitama Sule University Kano, Nigeria

 

Received: 16 March 2025/Accepted: 25 July 2025

 

Abstract

New Crescent Moon visibility has been extensively studied throughout history due to its undeniable importance in determining the Islamic calendar. Previous visibility models have relied on linear statistical theory, which does not fully account for the circular nature of the variables involved such as atmospheric turbulence, light pollution and limitations of optical equipment. In order to address this matter, this study proposed a new visibility using the limitation of New Crescent Moon sighting via an optical equipment. Data were categorized into two visibility categories, namely: visible to the theodolite and potentially requiring telescopes based on the night visibility that has been captured. The categorization is determined based on the residual local data observations collected in Sarawak, spanning from 1997 to 2023. The proposed limitation was applied by 31 positive data from 167 observations which results indicate that the visibility based on moon ages and altitude of the moon features parameter. This study suggested that the limitation of sighting the New Crescent Moon using an optical equipment range between 11 and 13 h of moon age with a moon altitude of 5° and 6°. These new criteria have a significant positive impact on enhancing the likelihood of observing the New Crescent Moon and improving the accuracy of the Islamic calendar especially in Sarawak.

 

Keywords: Correlation; limitation; New Crescent Moon; observation equipment; Sarawak

 

Abstrak

Kajian kenampakan Anak Bulan sangat penting dalam menentukan tarikh dalam kalendar Islam. Sebelum ini, parameter kenampakan Anak Bulan banyak bergantung pada teori statistik linear yang tidak mengambil kira faktor luaran seperti keadaan atmosfera, pencemaran cahaya dan keterbatasan peralatan optik. Oleh itu, kajian ini meneliti had kenampakan Anak Bulan dengan memberi tumpuan kepada keterbatasan peralatan optik dalam cerapan Anak Bulan. Data dikategorikan kepada dua jenis kenampakan iaitu boleh dilihat dengan theodolit dan boleh kelihatan menggunakan bantuan teleskop berdasarkan kenampakan. Pengelasan ini berdasarkan data cerapan yang dilakukan di Sarawak digumpulkan dari tahun 1997 hingga 2023. Limitasi yang dicadangkan menggunakan 31 data positif daripada 167 data cerapan bagi menentukan hubungan antara umur Anak Bulan dan altitudnya ketika kenampakan berlaku mengunakan peralatan. Hasil kajian menunjukkan bahawa Anak Bulan boleh dikesan menggunakan peralatan optik apabila usianya berada dalam julat 11 jam hingga 13 jam dan berada pada altitud 5 darjah dan 6 darjah. Penemuan ini memberikan sumbangan penting dalam meningkatkan ketepatan penentuan awal bulan Islam, terutamanya di Sarawak.

 

Kata kunci: Anak Bulan; korelasi; limitasi; peralatan cerapan; Sarawak

 

REFERENCES

Ahmad Hariz Bely, Roslan Umar, Nor Hazmin Sabri, Ahmad Lutfi Afifi Mohd, Nasir, Emma Zulaiha Zulkifli & Amirul Akmal Redzuan, Zamri Zainal Abidin, Jeff Hodgson & Arwin Juli Rakhmadi. 2025. Review on site suitability of observatory locations for astronomy purposes. Jurnal Fizik Malaysia 46(1): 10042-10055.

Ahmad Hariz Bely, Roslan Umar, Nor Hazmin Sabri, Zamri Zainal Abidin, Ahmad Lutfi Afifi Mohamad Nasir, Ihsanuddin Ismail, Razalie Hussaini, Emma Zulaiha Zulkifli & Arwin Juli Rakhmadi. 2024a. Light pollution monitoring through zenithal sky brightness at selected Malaysian observatories. Journal of Physics: Conference Series 2915(1): 012003.

Ahmad Hariz Bely, Ahmad Lutfi Afifi Mohd Nasir, Roslan Umar, Wan Mohd Yusof Wan Chik, Razalie Husaini, Mohamad Shobri Othman & Arwin Juli Rakhmadi. 2024b. Empowering astronomical exploration: Advancement of new moon observation devices in Sarawak, Malaysia. Iraqi Journal of Science 65(10(SI)): 6154-6162.

Bahagian Falak. 2022. Anak Bulan di Jabatan Mufti Negeri Sarawak, Temu bual, 12 Jun 2022.

Baharrudin Zainal. 2002. Pengenalan Ilmu Falak. Kuala Lumpur: Dewan Bahasa Dan Pustaka.

Bruin, F. 1977. The first visibility of the lunar crescent. Vistas in Astronomy 21(Part 4): 331-358.

Fatoohi, L.J., Stephenson, F.R. & Al-Dargazelli, S.S. 1998. The Danjon limit of first visibility of the lunar crescent. The Observatory p. 118.

Fotheringham, J.K. 1910. On the smallest visible phase of the moon. Monthly Notices of the Royal Astronomical Society 70(7): 527-532.

Ilyas, M. 1994. Lunar crescent visibility criterion and Islamic calendar. Quarterly Journal of the Royal Astronomical Society 35: 425-461.

Jabatan Mufti Sarawak. 2021. Latar Belakang Jabatan. Diakses pada 15 Mei. https://muftinegeri.sarawak.gov.my/modules/web/index.php

Maunder, E.W. 1911. On the smallest visible phase of the moon. The Journal of the British Astronomical Association 21(8): 355-362.

McNally, D. 1983. The length of the lunar crescent. Quarterly Journal of the Royal Astronomical Society 24: 417-429.

Muhamad Syazwan Faid, Mohd Saiful Anwar Mohd Nawawi, Mohd Hafiz Mohd Saadon, Raihana Abdul Wahab, Nazhatulshima Ahmad, Muhamad Syauqi Nahwandi, Ikramullah Ahmed & Ibrahim Mohamed. 2024. Assessment and review of modern lunar crescent visibility criterion. Icarus 412: 115970.

M.S. Faid, M.S.A. Mohd Nawawi & M.H. Mohd Saadon. 2023. Analysis tool for lunar crescent visibility criterion based on integrated lunar crescent database. Astronomy and Computing 45: 100752.

Nasir, A.L.A.M., Umar, R., Yussof, W.N.J.W., Ahmad, N., Zulkeflee, A.N., Sabri, N.H., Chik, W.M.Y.W., Mahiddin, N.A., Bely, A.H. & Izdihar, A.I.S. 2025. New crescent moon detection using Circular Hough Transform (CHT). Astronomy and Computing 51: 100902.

Nasir, A.L.A.M., Umar, R., Yussof, W.N.J.W., Ahmad, N., Sabri, N.H., Zulkeflee, A.N., Kamarulzaman, A.H. & Mahiddin, N.A. 2024. Comparative analysis of image processing technique in determining the new crescent moon visibility. Journal of Physics: Conference Series 2915(1): 012004.

Nazhatulshima Ahmad, Mohd Saiful Anwar Mohd Nawawi, Mohd Zambri Zainuddin, Zuhaili Mohd Nasir, Rossita Mohammad Yunus & Ibrahim Mohamed. 2020. A new crescent moon visibility criteria using circular regression model: A case study of Teluk Kemang, Malaysia. Sains Malaysiana 49(4): 859-870.

Nazhatulshima Ahmad, Nur Izzatul Najihah Mohamad, R. Abdul Wahab, MSA Mohd Nawawi, Mohd Zambri Zainuddin & Ibrahim Mohamed. 2022. Analysis data of the 22 years of observations on the Young crescent moon at Telok Kemang observatory in relation to the Imkanur Rukyah criteria 1995. Sains Malaysiana 51(10): 3415-3422.

Nurul Kausar Nizam, Mohd Saiful Anwar Mohd Nawawi, Mohammaddin Abdul Niri, Saadan Man & Mohd Zambri Zainuddin. 2014. Penggunaan teleskop: Kesan terhadap hukum ithbat kenampakan anak bulan di Malaysia. Jurnal Fiqh 11(1): 33-58.

Roslan Umar, Syed Mohd Hafiz Syed Omar, Nor Hazmin Sabri, Nur Athirah Ahmad Fashil & Ahmad Fazil. 2018. Pendekatan konsep tabayyun dalam isu falak kontemporari. BITARA International Journal of Civilizational Studies and Human Sciences 1(2): 36-43.

Roslan Umar, Mohd Khairul Amri Kamarudin, Wan Mohd Khairul & Ahmad Jazlan Mat Jusoh. 2017. Observations of the new moon using optical telescopes and radio telescope from the perspective of Islam. International Journal of Academic Research in Business and Social Sciences 7(8): 2222-6990.

Schaefer, B.E. 1996. An algorithm for predicting the visibility of the lunar crescent. Bulletin of the American Astronomical Society 19: 1042-1043.

Yallop, B.D. 1997. A method for predicting the first sighting of the new Crescent Moon. RGO NAO Technical Note 69.

Zulkeflee, A.N., Yussof, W.N.J.H.W., Umar, R., Ahmad, N., Mohamad, F.S., Man, M. & Awalludin, E.A. 2022. Detection of a new crescent moon using the Maximally Stable Extremal Regions (MSER) technique. Astronomy and Computing 41: 100651.

 

*Corresponding author; email: roslan@unisza.edu.my