Recent jac items

Editorial

Sat, 30 May 2026 00:00:00 +0000

Editorial

Zenith Passage Alignments at Koh Ker

Sat, 30 May 2026 00:00:00 +0000

Koh Ker is an ancient Khmer city built in Cambodia in the 10^th century CE. While most Khmer temple complexes were built with cardinal or near cardinal direction orientations, Koh Ker has a section that is instead oriented to sunrise on the day of zenith passage. The Koh Ker complex of Prasat Thom is linear and oriented to 14 degrees north of east. The Prang Pyramid at Prasat Thom’s western end overlooks the entire alignment to a flat horizon where the zenith passage sun rises. Along that same 14-degree axis are zenith passage tubes in roofs and linga statues acting as gnomons to capture the exact moment of zenith passage at noon. This report presents the results of a project to photo document the zenith passage sunrise alignment from the top of the Prang Pyramid. It ends by providing evidence that Koh Ker’s alignments are not an enigma by citing zenith passage related architectural features in Java, Sri Lanka, and the nearby Khmer city...

Mars excitement in Australian newspapers, 1877–1899: Humour and the public negotiation of astronomical knowledge

Sat, 30 May 2026 00:00:00 +0000

Speculation about Martian canals was a recurring feature of late nineteenth-century popular astronomy. This paper examines how colonial newspapers used humour to negotiate the epistemic uncertainty and interpretive excess associated with canal theory. Drawing on over one thousand metropolitan and regional Australian newspapers published between 1877 and 1899, we identify five overlapping modes of humour: imported metropolitan wit; satire of modern engineering culture; humour grounded in observational uncertainty; scale-based exaggeration and colonial self-comparison; and overt sceptical parody. These modes tracked shifting relationships between observation, interpretation and authority, allowing newspapers to entertain speculative ideas while marking the limits of scientific credibility. At the same time, humorous treatments positioned Australian readers within a global culture of science and modernity. Comparisons with projects such as the Suez and Panama Canals, and with...

Orientations of colonial churches in the Philippines and the island of Guam

Sat, 30 May 2026 00:00:00 +0000

The orientation pattern of the apses of 98 colonial Catholic churches in the Philippine archipelago (16th–19th centuries) and three in Guam (Mariana Islands, 17th century) has been studied and found not to follow the canonical eastward alignment toward sunrise, except perhaps in churches built during the 16th century. This suggests that pre-Council of Trent temple building traditions appear to have been preserved in some form initially, but were largely abandoned from the 17th century onwards. No relationship has been identified between orientation and religious factors such as founding orders or dedications, nor have consistent patterns been observed across most islands. Instead, geographical and environmental factors appear to have influenced church layout, this is more clear in Luzon. Naves were generally oriented to avoid the northeast–southeast monsoon axis; inland churches followed local valleys and rivers, while coastal churches were typically arranged perpendicular...

Book Review: Stonehenge: Sighting of the Sun