The Surya Siddhanta bridges this difference by juxtaposing the four solstitial and equinoctial points with four of the twelve boundaries of the rashis.
This misconception continues as there is not much difference between actual Uttarayana date which occurs a day after winter solstice (of Dec 21) when the Sun makes the northward journey, and 14 January.
In support of this proposal, he points to another tradition that the Uttarayana is considered the daytime of the Gods residing at the North Pole which tradition makes sense only if we define Uttarayana as the period between the Vernal and Autumnal equinoxes (when there is Midnight Sun at the North Pole).
Conversely, Dakshinaya is defined as the period between the Autumnal and Vernal Equinoxes, when there is midnight sun at the South Pole.
This festival is currently celebrated on the 14th or 15 January but due to axial precession of the Earth it will continue to shift away from the actual season.
[1] According to the Bhagavad Gita, a Hindu scripture, those who die when the Sun is on its northward course (from south to north) attain nirvana.
Devotees often take part in pilgrimages to bathe in Prayag, where the Yamuna, Ganga and Saraswati rivers meet.
On the first day, unwanted household items are discarded and burned in bonfires to symbolize starting anew.
The second day, people dress in new clothes and prepare pongal, a sweet dish that is made of rice, milk and jaggery, and offer it to Surya, the Hindu sun deity.
[13][14] Known as Lori in the northern states, children go door-to-door asking for sweets and money, and in the evening, people gather around huge bonfires to sing, dance, and make offerings to Agni, the fire deity, for future prosperity.
Traditional dishes made from flatbread and mustard leaves are shared with offerings of sesame brittle, peanuts, popcorn, and jaggery.