A week before the spring equinox, it was a warm, cloudless afternoon. The time was perhaps not the best time to venture into the landscape of the city of Jaipur — the desert capital of the Indian state of Rajasthan — but it was perfect for measuring time with the shadows cast by the sun.
I strode through the frenzy of the Johri Bazaar—Jaipur’s main market—past its coral walls, delicate latticework, and Mughal arches, as I made my way to Jantar Mantar, the mysterious Indian gateway to the stars.
At first glance, this open-air complex, filled with strange gabled walls and stairs that lead nowhere, seems out of place. It lacks the ornamentation of the City Palace that surrounds it, nor the complexity of the respected Govind Dev Ji temple and nearby Hawa Mahal (Palace of the Winds).
But this site—a collection of 20 scientific sculptures known as yantras, 300 years old, that can measure the positions of stars and planets, calculating time accurately—had mystified me since childhood here in Jaipur, when structures looked like giant versions of the delicate instruments in my school geometry kit.
Years later, as a professional architect, I could better understand its use. They are ingenious architectural solutions for understanding the mechanics of astronomy and fundamental tools for traditional Hindu astrologers to be able to make astrological charts and predict auspicious dates.
In 1727, when the region’s king, Sawai Jai Singh, conceived Jaipur as his capital and the country’s first planned city, he wanted to design it based on the principles of Vastu Shastra, which makes use of nature, astronomy and astrology. to design the architecture and planning.
He realized that to perfectly align Jaipur with the stars, aid astrological practices, and predict weather events important to agricultural production, accurate and affordable instruments would be needed.
But after sending research teams across Central Asia and Europe to collect data on the knowledge of Islamic and European scientists, Sawai Jai Singh found discrepancies between the readings of brass instruments that were widely used at the time.
To increase this precision, he increased the size of the instruments to scale, stabilized them by reducing moving parts, and made them resistant to wear and tear and weather conditions, using marble and local stones in their construction. He then used these innovations to build five open-air observatories in the Indian cities of Jaipur, Delhi, Ujjain, Varanasi and Mathura—the Jantar Mantar.
Four Jantar Mantar survive today (the one in Mathura was demolished), but the one in Jaipur, opened in 1734, is the largest and most complete. Today, it is a UNESCO World Heritage Site, not only because it is the best-preserved observatory of its kind in India, but because, according to UNESCO, it represents innovations in architecture, astronomy and cosmology, as well as learnings and traditions from Western culture, from the Middle East, Asia and Africa.
“Dinner” in Sanskrit means instruments and “mantar” means calculator. Therefore, each yantra in the complex has a mathematical purpose. Some are sundials that indicate local time and the position of the Sun on the hemisphere; others measure the movements of planets and constellations to detect zodiac signs and guide predictions.
The largest of all is a huge equinoctial sundial known as the Samrat Yantra: a triangular wall 27 meters high and two thin semicircular ramps, which radiate like wings from its sides. Below him, my guide indicated the shadow over one of the ramps as it moved at precisely 1mm per second, indicating local time to within two seconds.
Another yantra, Jai Prakash, measures the path of the Sun through the Indian Vedic zodiac signs to determine the horoscope. Its bowl-shaped structure, dug into the ground, is like an inverted map of the sky, and a tiny metal plate suspended over a crossed wire sets a shadow that shows the position of a given planet or star.
“I used these instruments many times in my two years of masters,” says Neha Sharma, now a PhD in Vedic astrology (Jyotish Shastra) from the University of Rajasthan in India. “Learning to read these instruments and do calculations with them is still a mandatory part of the curriculum for anyone who wants to take astrology as a career option.”
But most of the modern scientific world regarded the Jantar Mantar observatories as a curiosity until renowned Indian astrophysicist Nandivada Rathnasree argued that the structures were still useful.
In her role as director of the Nehru Planetarium in New Delhi — from 1999 to her death in 2021 — she encouraged astronomy students to gain hands-on experience on the position of the stars at the various Jantar Mantar, which led to academic recognition. and international of observatories.
“It was Nandivada Rathnasree who threw the scientific community’s spotlight on the Jantar Mantar,” according to Rima Hooja, archaeologist and advisory director of the Maharaja Sawai Man Singh 2nd Museum, at Palácio da Cidade. “Her role as hers was also instrumental in the recognition of the Jantar Mantar of Jaipur as a UNESCO World Heritage Site.”
The Jantar Mantar continue to gain fame, not only for their architectural genius, but for their classic style.
“On the surface, Jantar Mantar may look like they don’t belong in the local architecture,” says conservation architect Kavita Jain, who lives in Jaipur. “But when you look closely, the huge sundial is stable by creating arch-shaped voids. The Hindu canopies that crown the instruments, marble and stones used in the construction — all are reminiscent of local architectural traditions. “
Today, tourists, students and scientists from many disciplines and cultures around the world understand that Jaipur’s Jantar Mantar is much more than a historic monument. Situated in the center of an ancient and thriving city of forts and palaces, its monolithic structures continue to mirror the cosmos and create a lasting legacy.
Have you watched our new videos on YouTube? Subscribe to our channel!