PANCHANG GYAN - Calculation of LAGNAM We know that Sun travels through the 12 zodiac signs (rasis) in one year; that is one rasi per Tamil month. On Tamil New year day (Chiththirai first day), Sun enters the first rasi - Mesham. On Vaikasi 1st, he enters the second rasi - Rishabam. And so on. Since each rasi subtends an arc of 30 degrees, he travels app. 1 deg per day. Every day, the Sun travels through all the 12 rasis. Now these are called as LAGNAS of the day. At the exact time of sunrise, it starts in the rasi (lagnam) corresponding to the month (Chithrai = Mesham etc). and after travelling thru that lagnam, it enters the next lagnam, travels thru this lagnam, then enters 3rd lagnam -- etc etc, till the next sunrise. Thus, we see that the time taken to travel thru one lagnam will be 24 hours / 12 lagnams = 2 hours (approx ) in one lagnam. Converting this in Tamil units, it would mean 5 naazhigais per lagnam (one hour = 2 1/2 naazhigais). But it is exactly not so. The time per lagna...