Ayana

(“going”) In the estimation of the
Hindu calendar, the word ayana refers
to the movement of the sun during its
yearly course, which is divided according to the direction of the sun’s movement. The six months that the sun
moves in a northerly direction is called
the uttarayana, and its southward
movement in the following six months
is the dakshinayana. The transition
points at which the sun changes direction do not fall on the solstices, as figured in the Gregorian calendar, but
about three weeks later on Makara
Sankranti (around January 14) and
Karka Sankranti (around July 14).
The sun’s northward journey is
considered a more auspicious time
than the southward journey, although
many other factors can influence the
judgment of a particular day.