Naga

Naga is the tenth karana and the third of the four fixed (sthira) karanas, occurring once in the lunar month on the second half of the new-moon tithi. Its name means serpent, tying it to the Nagas, the serpent spirits, and the almanac tradition gives it a correspondingly cautious, potent character belonging to the dark of the Moon. As a fixed karana it does not rotate but appears at a set point around the conjunction of Sun and Moon. The panchanga treats this new-moon period as suited to ancestral and inward observance rather than bright undertakings. These are the conventions of the calendar tradition, in which the four fixed karanas mark the transition across the new moon while the seven movable karanas carry the rest of the month.

The serpent imagery of Naga connects it to the wider place of serpents in Hindu cosmology as beings of the underworld and as intermediaries with the ancestors, the pitrs, whose ritual worship, shraddha, is itself concentrated in the dark fortnight and especially near the new moon; the almanac's reading of Naga as suited to inward and ancestral rather than outward observance follows the same logic that governs the whole cluster of fixed karanas at this point in the month. Naga occupies the second half of the new-moon tithi itself, immediately before the lunation completes, making it, with Chatushpada, one of the two karanas that span the moment of conjunction between Sun and Moon around which the whole fixed group is built.

Naga is the third of the four fixed karanas and occupies position 60, the second half of tithi 30. Tithi 30 is Amavasya, so Naga is the final half-tithi of the lunation, ending at the exact moment of the new moon, after which the count restarts at position 1 with Kimstughna.

That makes it the only karana whose end is an astronomical event rather than an arbitrary six degree step. Every other karana boundary falls where the Moon has gained a further six degrees on the Sun from wherever the count began; the boundary at the end of Naga is the conjunction itself, elongation zero, and the whole numbering of tithis and karanas is anchored to it.

The four fixed karanas exist for an arithmetic reason. Sixty karanas cannot be filled by a rotation of seven, but fifty six can, eight times over, so four positions are taken out of the rotation. All four were placed around the conjunction: Shakuni, Chatushpada and Naga at the close of the waning fortnight and Kimstughna at the head of the waxing one. The result is a run of four consecutive half-tithis, roughly two days, in which no movable karana appears, and a seven-fold cycle that runs unbroken from position 2 to position 57 in every lunation.

A karana averages 11 hours and 49 minutes and can be two hours or so shorter or longer depending on the Moon's speed.