The astronomical mysteries of Goan Churches

Imagine, if you can, a magnificent beam of natural sunlight shining through the window of a church, perfectly illuminating the Christ on the cross. What kind of astronomical brilliance would facilitate this divine experience? Sarvesh Sinai Borkar unravels the mystery…

The Portuguese architecture of Goan churches, whether with their front façade directed at the rising or setting sun, was always planned to have the backdrop of an open expanse and large paddy fields or a formidable location atop a hillock dominating the rest of the landscape. An exception to this rule is the Holy Spirit Church of Margao (Espirito Santo)which is located inside the open space refered to as the ‘square’ surrounded by noble houses. On September 22, just before sunset, Fr. Nascimento Jose Mascarenhas, a priest and historian currently residing in the Holy Spirit Church, was witness to a divine astronomical moment that Sarvesh Borkar, as an archeoastronomy enthusiast, had studied and predicted. Just before sunset on equinox, as the sun traversed the sky, a brillant beam of sunlight shone through the round oculus window of the unique west-facing façade of the church, suddenly illuminating the Christ on the cross in the main altar for three to four spellbinding minutes.

Witnessing the light of the setting sun in this fitting position was truly an unforgettable moment, and this spectacle dates back to when the Margao church was re-built between 1595 and 1645 during the process of its destruction and reconstruction. This church also has a unique display of well-illuminated interiors with doors and windows covered on the inside, with sea-shell shaped semi-domes (like those commonly found on Goan sea -shores) – an aspect which is interestingly not seen in any of the earlier churches built before 1595 in Goa during the old conquest.

The master architect of this Goan- Portuguese masterpiece had incorporated the scientific legacy of astronomical orientation of churches which involves controlled use of sunlight to illuminate selected portions of its interiors with natural sunlight at a specific time on particular days of the year.

Borkar asserted that this was the intention of the builders – an attempt to reflect the general understanding of the relation of human activities to the cosmos. Astronomical knowledge was developed, preserved, and transmitted as part of a broader intellectual enterprise, overlapping with the theoretical study of natural philosophy, with practical studies related to the maintenance of the religious calendar, and with those practical activities related to keeping the time of day for religious and civil purposes.

As per Borkar’s hypothesis, the east-west facing Portuguese architectural churches built between the 16th and 17th centuries during the old conquest in Goa had embodied astronomical principles in a myriad of ways. Some used the changing light of sunbeams for timekeeping while some incorporated formal timekeepers like sundials, while many of the old conquest churches served as practical observatories where the rising and setting sun was aligned on the equinox and solstice day with the western or eastern entrance.

To name a few, the church of St Augustine which is now in ruins, was oriented eastwards on the Holy Mount (Monte Santo) towards downtown old Goa and it would be illuminated by a beam of sunlight from the rising sun at a specific time on August 28 – the feast day of saints. Another interesting aspect of this church was the simple, chamberlike design of the rear lighting of the holy sacrament in the main altar, so that the light during sunset illuminates the chamber from behind, through a window opened in the church’s rear wall behind the altar.

Similar arrangements can be seen in the existing churches of St Francis of Assisi at Old Goa and Santana church in Talaulim. The former’s front façade orients towards the setting sun on November 2 – the all souls day, whereas the latter’s is oriented towards the rising sun on the same day.

Text & Images: Sarvesh Sinai Borkar

For us at Planet-Goa, our team is driven by that feeling of exhilaration that one gets when discovering that something ‘unique’ and ‘new’ about Goa for our ever-so-discerning readers.



Author: Planet Goa Team
For us at Planet-Goa, our team is driven by that feeling of exhilaration that one gets when discovering that something ‘unique’ and ‘new’ about Goa for our ever-so-discerning readers.

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