The existence of a true ninth planet of the Solar System was proposed by astrophysicists at the California Institute of Technology in Pasadena. It was based on the observation of a possible ice giant which seemed to show up on the wide field infra-red Survey Explorer undertaken by NASA.

Astrophysicists at the University of Bern have created a model of the possible planet in the outer solar system. The celestial body is likely to be of a radius 3.7 times that of Earth. With a temperature of 226 degrees Celsius, it is likely to have an envelope of helium and hydrogen.

Planet 9 is likely to be a smaller version of Neptune or Uranus. It would have also formed 4.6 billion years ago along with the other planets that evolved in the solar system as per the model projections. The study now gives physical properties to what was earlier just a simple point mass.

While more science projects  from the Large Synoptic Survey Telescope in the future will be able to give us a better idea of just what this Planet 9 is like or if it exists at all, it is interesting to note what educated guesses the astrophysicists have taken at this point of time.