August 22, 2017

Part of the Jantar Mantar observatory complex in New Delhi, India

The people of New Delhi, India’s capital city, won’t be able to see today’s total solar eclipse. But they still get astronomical bragging rights—for nearly three centuries they’ve hosted one of the world’s most striking observatories. Built in the 1720s, the astronomical instruments that make up Jantar Mantar are geometric forms constructed at such a large scale that they could measure time and track heavenly bodies with unprecedented precision. The structure seen here is called the Rama Yantra, and was used to observe the position of celestial objects like stars and planets. The observatory complex also includes an enormous sundial that could measure time to an accuracy of 2 seconds, a degree of precision never previously achieved. The Maharaja Jai Singh II commissioned the construction of five such observatories across northern India between 1721 and 1730, each named Jantar Mantar. By locating the sites in different locations, astronomers could compare readings from different coordinates, enabling them to achieve greater accuracy.