In the Vedic literature we read of greatly advanced yogis and rishis like Narada Muni who was not only able to travel from one planet to another but was also able to leave the material universe at will and travel to the spiritual abode of the Lord in Vaikuntha and return. For such sages advanced knowledge of the astronomical conditions of our universe goes without saying.

Image copyright: The Bhaktivedanta Book Trust -- www.Krishna.com