Some say that on January 1, 2018, the Moon was in Ardra Nakshatra. Actually it was not. Calculations were made thousands of years ago by ancient Jyotish masters. Over time, subtle shifts in the earth’s poles, etc. make a difference, even though those shifts are indeed subtle. The ancient Jyotish masters did refer to those shifts, but today many still refer to the parameters of ancient times.
The Moon was full January 1. It was then also in its closest position relative to earth as per
the National Ocean Service. This makes it appear larger and brighter… a “supermoon”. However, though that of course has some effect, it is not a significant Jyotish consideration. There is no critical point/Nadi associated with that.
Some consider the astrology of January 1 to be like the birth chart of the upcoming year. That is also not really valid because January 1 has no astronomical/astrological significance. It is essentially just an arbitrary selection of the beginning of the year.
This is not meant to be critical of some approaches. However, the information is important (and in fact profound) meriting consideration.