This December 21st marks a very significant day astrologically. Not only is it the winter solstice, but it is a new moon.
On winter solstice the old sun dies ( metaphorically) and then rests till Dec.25th when the new sun is born. It is the real new years. And what our intentions are will carry on for the next year. It is a great time to release anything you wish to that no longer serves you and to open doors for things of more value to enter.
Additionally, because it is a new moon the energies are intensified and it is possible to use this available moon power to work in your favour. As it is a new moon it signals the time of new beginnings and its wonderful to make a list of things you wish to bring into your life.
Therefore, release all that which is old and bring in all that which will help you grow in the new year.
Here is a link to an article that goes more into detail and is very interesting to read.