|Jai Prakash Yantra|
One of Maharaja Sawai Jai Singh's interest was in astronomy. He kept his scientific interest alive by building solar observatories. The king has built five observatories, respectively in Delhi, Ujjain, Mathura, Varanasi and of course, Jaipur. Only the one in Jaipur is still operational, preserved since the first half of the 18th centure. That - was the one we went to.
The photo above is Jai Prakash Yantra. It comprises of two sunken hemispheres, mapping out the heavens. They are used to locate the position of stars based on two different coordinates measurements systems, the horizontal and celestial equatorial systems. This was believed to be invented by Jai Singh himself to verify the accuracy of other instrument in the observatory.
This sundial also used to forecats the ccrop prospects for the year. In this same observatory, Samrat Yantra has a small "little brother" - a smaller version of sundial named Laghu Samrat Yantra. This is used to calculate Jaipur's local time up to an accuracy of 20 seconds.
We had our guide with us at this location as well, and he was a strict guide, always giving us a time limit to 'regroup'. = ="
Side note: Have you heard of the 5:2 diet?