In many of Buddha sermons recorded and passed down today, He mentioned about the 10000 world system. There are immeasurable beings living in other planets other than Jumbudiva (the present earth planet). In the 1500s, Galileo uses Telescope to see thing in the vast space, and with modern astronomy proving that not only Earth and other planets revolve around the sun but also countless of other suns and solar system. Another fact to show the vastness of space (universe) we the Earth planet is just one of the many planets revolving around many other suns and solar systems and planets.
In the modern science, minimum 100 planets has been identified so far but the Buddha stated that "the infinite world spheres are incalculable". In one of Buddha sermon in the Brahmajala Sutta, Digha Nikaya, Sutta Pitaka? He said: "He recalls to mind his various temporary states in days gone by- one birth, or two or three or four or five birthds, 10 or 20 or 50 a 100 or a 100,000 births, through many cycles of cosmic contraction and cosmic expansion....Now there comes a time, when sooner or later, after the lapse of a long, long period of contraction, this world-system passes away. And when this happends beings have mostly been re-born in the World of Radiance, and there they dwell made of mind, feeding on joy, radiating light from themselves, traversing the air, dwelling in glory; and thus they remain for a long, long period of time. Now there comes also a time, friends, when sooner or later, this universe begins to re-evolve by expansion."
From the above passage, Buddha described beings in the other planet, they might be in a level of the 33 heaven in existence such as the heaven of light and sound, whereby beings radiated lights and sound within themselves...
There are ancient records of how Buddha viewed our planets and other planets...i believe its not something being madeup or fabricated by an enlightened being like him.