{"id":21804,"date":"2026-10-14T17:36:26","date_gmt":"2026-10-14T10:36:26","guid":{"rendered":"https:\/\/fsh.walisongo.ac.id\/?p=21804"},"modified":"2026-10-14T17:36:26","modified_gmt":"2026-10-14T10:36:26","slug":"when-astronomical-models-meet-the-real-sky-uin-walisongo-conference-examines-the-limits-of-calculation","status":"publish","type":"post","link":"https:\/\/fsh.walisongo.ac.id\/?p=21804","title":{"rendered":"When Astronomical Models Meet the Real Sky: UIN Walisongo Conference Examines the Limits of Calculation"},"content":{"rendered":"

FSH Online, Semarang, Indonesia<\/strong> \u2014 Astronomical calculations can provide precise predictions, but observing the sky involves more than numbers alone. Atmospheric conditions, the brightness of the sky, instrument performance, and the physical characteristics of celestial objects can all influence what observers actually see.<\/p>\n

 <\/p>\n

The relationship between computational precision and observational reality was a key theme of the Annual International Conference on Islamic Astronomy (ALICIA), held on Wednesday, 14 October 2026, at UIN Walisongo Semarang. The conference gathered 157 students at the IsDB Theatre Hall of the Faculty of Sharia and Law to examine the future of Islamic astronomy in an increasingly digital age.<\/p>\n

 <\/p>\n

Judhistira Aria Utama, representing the Earth and Space Education, Exploration, Mitigation and Protection research group, presented \u201cZawal’s Ihtiyatir: Between Computational Tolerance and Bio-Optical Reality.\u201d The topic brought attention to the relationship between calculated astronomical parameters, the tolerances used in computational methods, and the conditions under which astronomical phenomena are observed.<\/p>\n

 <\/p>\n

The concept of zawal is associated with the Sun’s passage across the local meridian and is relevant to discussions of solar position and prayer-time determination. The specific meaning of \u201cIhtiyatir\u201d in the presentation title would require confirmation from the speaker or conference materials; therefore, its technical interpretation should not be assumed from the title alone.<\/p>\n

 <\/p>\n

More broadly, the topic raises an important issue in applied astronomy: a mathematically calculated value and a real-world observation do not always tell the whole story independently. Computational models describe celestial positions and movements, while actual observations take place through an atmosphere and with instruments\u2014or human vision\u2014that have practical limitations.<\/p>\n

 <\/p>\n

This distinction is particularly important in the study of the crescent moon, or hilal. The Moon’s altitude and angular separation from the Sun can be calculated, but visibility also depends on factors such as atmospheric transparency, sky brightness, the crescent’s contrast, and the observer’s equipment and experience.<\/p>\n

 <\/p>\n

Judhistira Aria Utama has explored these issues in his published commentary on the consistency of crescent-visibility criteria for Ramadan 1446 H in 2025. The analysis discusses how astronomical calculations and visibility criteria can produce different assessments of where the crescent may be observed. His work highlights the importance of examining the physical conditions underlying numerical thresholds rather than treating calculations as isolated figures.<\/p>\n

 <\/p>\n

A further article published by Universitas Pendidikan Indonesia in March 2026 examined crescent visibility using a photometric model that considered atmospheric extinction, twilight sky brightness, and the relative positions of the Sun and Moon. Such approaches illustrate how observational science can add important context to geometrical calculations.<\/p>\n

 <\/p>\n

These questions matter for Islamic astronomy because astronomical findings inform religious and public decisions, including the determination of Hijri months. Clear methods, carefully evaluated evidence, and transparent explanations can help researchers and the public understand both the strengths and the limitations of different approaches.<\/p>\n

 <\/p>\n

ALICIA 2026 was officially opened by Prof. Dr. H. Imam Yahya, M.Ag., Vice Rector I of UIN Walisongo, as keynote speaker. Dr. H. Tolkah, M.A., Dean of the Faculty of Sharia and Law, delivered the welcoming remarks.<\/p>\n

 <\/p>\n

The conference’s main theme, \u201cFrom Manual Calculation to Computational Excellence: Transforming Islamic Astronomy in ASEAN through Automated Systems,\u201d provided a framework for discussing how automation can improve astronomical work while maintaining scientific rigour.<\/p>\n

 <\/p>\n

Other speakers included Prof. Dr. H. A. Izzuddin, M.Ag., Professor of Islamic Astronomy at UIN Walisongo, who discussed the transition from manual calculations to automated systems, and Mr. Mohd Razlan Bin Ahmad of UiTM Malaysia, who explored digital integration in Islamic astronomy education.<\/p>\n

 <\/p>\n

For students and researchers, the broader lesson is that computational excellence does not mean relying on numbers without question. It means developing models carefully, understanding their limits, testing them against observations, and explaining the evidence clearly.<\/p>\n

 <\/p>\n

As Islamic astronomy continues to adopt new technologies, the strongest results will come from bringing together mathematical precision, reliable observation, and critical scientific judgement.<\/p>\n","protected":false},"excerpt":{"rendered":"

FSH Online, Semarang, Indonesia \u2014 Astronomical calculations can provide precise predictions, but observing the sky involves more than numbers alone. Atmospheric conditions, the brightness of the sky, instrument performance, and […]<\/p>\n","protected":false},"author":14,"featured_media":21805,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[14,27],"tags":[],"class_list":["post-21804","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-agenda-kegiatan","category-kunjungan"],"_links":{"self":[{"href":"https:\/\/fsh.walisongo.ac.id\/index.php?rest_route=\/wp\/v2\/posts\/21804","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fsh.walisongo.ac.id\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fsh.walisongo.ac.id\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fsh.walisongo.ac.id\/index.php?rest_route=\/wp\/v2\/users\/14"}],"replies":[{"embeddable":true,"href":"https:\/\/fsh.walisongo.ac.id\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=21804"}],"version-history":[{"count":1,"href":"https:\/\/fsh.walisongo.ac.id\/index.php?rest_route=\/wp\/v2\/posts\/21804\/revisions"}],"predecessor-version":[{"id":21806,"href":"https:\/\/fsh.walisongo.ac.id\/index.php?rest_route=\/wp\/v2\/posts\/21804\/revisions\/21806"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/fsh.walisongo.ac.id\/index.php?rest_route=\/wp\/v2\/media\/21805"}],"wp:attachment":[{"href":"https:\/\/fsh.walisongo.ac.id\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=21804"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fsh.walisongo.ac.id\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=21804"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fsh.walisongo.ac.id\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=21804"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}