If winter solstice is in Dec 23, why is Uttaraayan on Jan 15?

The sun's entering Capricorn is known as Makar Sankranti or Uttarayan and its passage from Capricorn to Gemini is the Uttarayan period. The solstices and the sankrantis do not happen on the same day, hence the confusion. read more

To be quite correct, the northern-hemisphere winter solstice is the instant when the sun’s geocentric longitude is exactly 270 degrees. Due to nutation, the sun won’t be exactly over the Tropic of Capricorn at that instant, and the time between one winter solstice and the next isn’t exactly one year. read more

- Mayank Vahia uses history and astronomy to explain why we celebrate this Indian festival on a specific day according to the solar calendar, instead of the lunar calendar like other festivals in the country. read more