The Sun’s apparent motion in the sky when viewed from the Earth can be divided into the northern and the southern paths in the course of one solar year. The six month period from the Winter Solstice (December 21st) to the Summer Solstice (June 20th) is called the Uttarāyana and the six month period between the Summer Solstice and the Winter Solstice is called the Dakshināyana. The apparent motion of the Sun is towards the North in Uttarayana and towards the South in Dakshinayana.
According to the Lunar calendar, the Dakshināyana occurs between the months of Ashādha and Margasīrsha and the Uttarāyana between the months of Māgha and Jyēshta.
The Sun is the cause of day and night. He also causes the upward and downward currents of ether and the annual waters of the rains. Similarly, he causes the sublimation of matter into spirit in Uttarayana and the precipitation of spirit into matter in Dakshinayana. The journey of Sun along the southern path awakens the consciousness of man into objectivity while the reverse holds true for the northern path. Hence, the period of Dakshinayana has been called the gateway into the material planes of existence.
It must be observed that almost all of the important festivals and days of spiritual significance celebrated in the Sanātana Dharma occur within the Dakshinayana period of six months. These days of spiritual significance like Vināyaka Chavithi (auspicious for the worship of Lord Ganesha), Navarātras (auspicious for the worship of the Divine Mother), Kārtīka Pūrnima etc. act as markers in the journey of the soul towards the divine and help awaken the soul from passive objectivity into active subjectivity or the ātma. These festivals and religious observances have been established by our ancients to prevent the fall of man into objectivity. They aid him in the battle with his inner enemies represented by the shadripus or the six enemies – lust, anger, greed, attachment, arrogance and jealousy.
The Vishnu Purana declares that one human year is equivalent to one day for the Devas. Therefore, the six months of the Dakshinayana are equivalent to one night and the six months of the Uttarayana are equivalent to one day for the Dēvas.
In the coming months, may we seek the light and be blessed with divine grace allowing us to conquer the negative forces within and without.