Dakshinayan Sun duration every year

Based on sun movement, the year is divided into 2 period called Uttarayan and Dakshinayan. When sun moves towards north, it is called Uttarayan and southward movement of the Sun is called Dakshinayan. When sun enters in Makar rashi (on the day of Makar Sankranti) it turns Uttarayan and when the Sun enters in Cancer rashi, it becomes Dakshinayan. Dakshinayan is considered as inauspicious