A complete survey of forty-eight Christian churches on the Canary Island of Fuerteventura finds that the great majority follow the standard east-facing tradition, yet a smaller group share an unexpected south-east orientation that coincides with the rising of Sirius—known locally to farmers as the Gañanera star—during the seventeenth century.
The study, led by Mariano F. Muratore of Argentina’s CONICET and Juan Antonio Belmonte of the Instituto de Astrofísica de Canarias, measured each building’s axis and horizon to calculate celestial declination. Thirty-four churches—about seventy per cent of the sample and ninety-one per cent of those erected before 1900—fall neatly within the solar arc, so their altars greet the Sun on at least one day of the year. Many of these also include a sheltered side door on the leeward wall, a practical concession to the island’s persistent north-east trade winds .
When the axes were plotted, two peaks emerged. One cluster, just north of due east, matches sunrise on Easter Sunday calculated for the construction year of each church, suggesting that some builders timed orientation to that movable feast. The second peak centres on a declination of about minus fourteen degrees. Solar or topographic explanations cannot fully account for this value, but the declination overlaps the position of Sirius in the seventeenth century, the period when several of the south-eastern-facing churches were founded.
Ethnographic interviews recorded in the 1990s bolster the stellar link. Elderly ploughmen from central Fuerteventura recalled rising before dawn to watch the bright Gañanera over the sea; they judged the star’s height to decide when to sow. One oft-cited example is the church of Nuestra Señora de Guadalupe in Agua de Bueyes, built around 1642. Viewed from its main doorway, the horizon line matches Sirius’s historic rising point, and two carved rosettes on the entrance arch evoke celestial symbols.
The authors note that neighbouring Lanzarote shows a different pattern: many chapels there rotate north-east so that congregants enter out of the wind, sacrificing the canonical eastward altar. Fuerteventura’s builders, by contrast, kept the liturgical orientation and solved the wind problem with side doors, making the island a rare case where ritual, climate and perhaps a pre-Christian star cult were balanced in the same blueprint.
The findings appear in On the orientation of historic Christian churches of Fuerteventura: conciliating tradition, winds and topography, a paper by Muratore, Gangui, Urrutia-Aparicio, Cabrera and Belmonte. The study was published online on arXiv in May.
Whether the south-east group truly “aims” at Sirius remains open, but the survey adds a provocative data point to the growing field of church-orientation studies and invites fresh exploration of how local sky lore may have guided colonial builders.
Produced with the assistance of a news-analysis system.