The regal-sounding Aristarchus of Samos (ca. 310-ca. 230 BC) was an ancient Greek mathematician and astronomer (I don’t mean he was old and wizened!). He was kind of bored, as Medusa and all the other monsters had been killed by the Grecian heroes and even the Persians had been defeated by the three-hundred Spartans. (Aristarchus modeled his look on Gerard Butler.)
So, being at a loose end, he got to thinking about the world and the stars and realized the only thing that made sense was that the Earth and other planets traveled around the Sun! This system is now known as the “heliocentric” model (Helio – Greek for “sun”, centric – Greek for center). His theory preceded that of Copernicus by over fifteen hundred years.
Not only that, but Aristarchus was also the first person to correctly order the planets around the Sun according to their distance. And he suggested that the stars were identical to the Sun but were so far away that they didn’t appear to move – all this while chewing on a kebab and glugging wine!
Aristarchus made the first documented attempts to scientifically deduce the size of the universe and used trigonometry to determine the size of the moon (you knew it had to be good for something – right?). The figure he arrived at was between 0.32 and 0.40 times the diameter of Earth – the true value is 0.27. His other calculations weren’t as close due to limitations of naked eye observations, but his overall method was sound.
The heliocentric view was opposed by many at the time and afterwards on religious grounds, until the idea was finally “rediscovered” by Nicolaus Copernicus in 1543 after he hacked Aristarchus’ Facebook account and realized everybody had forgotten about the old Greek guy.