Abstract:
Here we propose the possibility that the recently postulated Neptune-sized planet with an orbital period of 15,000 years could be a gravitationally condensed dark matter (DM) object. The observed mass of Planet Nine fits with the theoretical mass predicted for such DM objects formed by 60 GeV DM particles, which is the currently favoured DM particles. This object could also provide us with a testing ground for modification of Newtonian dynamics.