Lunar eclipses

A lunar eclipse will be seen from Mumbai starting at 10:37 PM Indian Standard Time today, and will last till 2:42 AM tomorrow. The maximum will occur at 40 minutes past midnight. The eclipse will be visible from most of India, and will occur at about the same times. The prediction of eclipses is a routine task today, done with high precision. But positional astronomy is an ancient subject, and was done accurately for millennia all over the world, even when the causes behind them was obscure. In India computations of eclipses involved two entities, which were named Rahu and Ketu, which moved in a cycle which is known as the saros. In modern day terminology of positional astronomy, Rahu and Ketu correspond to the points on the celestial sphere where the apparent paths of the sun and the moon coincide. As a result, these are the only places on the celestial sphere at which eclipses can take place.

In this wonderful low-relief sculpture at the entrance to the Sri Krishna temple in Hampi, Rahu and Ketu are represented as snakes, ready to swallow the moon. As for the rabbit, I looked again at a photo of the full moon I’d taken in March in Mumbai, and with a little squinting I could imagine that the dark patches of the lowlands on the disk look a bit like a leaping rabbit. You can take a look for yourself tomorrow and decide. In any case, I found the gate beautiful. How deeply astronomy is imbedded into all of world’s cultures!