From past experience I think we can all agree it's never safe to judge by appearances, and this is most probably far more accurate of astronomy when compared to almost everything else.
For example, in times past the notion which one would most naturally form of the earth and heaven is that the solid earth on which we live and move extends to a great distance in every direction, and that the heaven is an immense dome upon the inner surface of which the stars are fixed.
In ancient astronomy such an idea of the universe was held by men from the earliest of times. In their perspective the earth was of vital importance.
The sun and moon were simply lamps for the day and for the night; and these, if not gods themselves, were at any rate under the charge of extraordinary deities, whose task it was to guide their motions across the vaulted sky.
Slowly and gradually, however, this simple estimate of nature began to be overturned. Challenging problems agitated the human mind. On what, for instance, did the solid earth rest, and what prevented the vaulted heaven from falling in upon men and crushing them out of existence?
In ancient astronomy extraordinary misguided beliefs sprang from vain attempts to solve these riddles. The Hindoos, for instance, believed the earth was supported by 4 elephants which stood on the back of a massive tortoise, which, in its turn, floated on the surface of an elemental ocean.
The early Western civilisations conceived the fable of the Titan Atlas, who, as a punishment for revolt against the Olympian gods, was condemned to hold up the expanse of sky for ever and ever.
Down the line, glimmerings of the true light began to break in upon men. The Greek philosophers, who busied themselves with such issues, progressively became convinced that the earth was spherical in shape, that is to say, round like a ball. In this we now know that they were correct; but in another important belief, that the earth was located at the center of all things, they were very far off course.
Then by the second century of the Christian era, the ideas of the early philosophers had become hardened into a definite theory, which, though it appears incorrect to us to-day, demands exceptional notice from the fact that it was accepted everywhere as the legitimate explanation until as late as just five centuries ago.
This theory of the universe is known by the name of the Ptolemaic System, because it was first set forth in definite terms by essentially the most famous of the astronomers of antiquity, Claudius Ptolemæus Pelusinensis who lived (100-170 A.D.), better known as Ptolemy of Alexandria.
In his system the Earth occupied the centre; while around it circled in order outwards the Moon, the planets Mercury and Venus, the Sun, and then the planets Mars, Jupiter, and Saturn. Beyond these again revolved the background of the heaven, upon which it was believed that the stars were fixed.
The Ptolemaic system persisted unshaken for about fourteen hundred years after the death of its author. Clearly men were flattered by the notion that their earth was the most important body in nature, that it stood still at the centre of the universe, and was the pivot upon which all things revolved.