There is little existing evidence concerning the origin of Aristarchus's belief in a heliocentric system. We know of no earlier hypothesis of this type but in fact the theory was not accepted by the Greeks so apparently never had any popularity. We only know of Aristarchus's theory because of a summary statement made in Archimedes' The Sand-Reckoner and a similar reference by Plutarch.And this website is another scholarly treatment of Aristarchus. It says:
Copernicus himself originally gave credit to Aristarchus in his own heliocentric treatise, De revolutionibus caelestibus , where he had written, "Philolaus [see below] believed in the mobility of the earth, and some even say that Aristarchus of Samos was of that opinion." Interestingly, this passage was crossed out shortly before publication, maybe because Copernicus decided his treatise would stand on its own merit.It also says that Aristarchus claimed: "The moon receives its light from the sun." And:
In terms of heliocentricity or the movement of the earth, the only person to follow Aristarchus' philosophy was Seleucus, who in 150 BC attributed the ocean tides to the stirring of air caused by the rotation of the earth and its interaction with the revolution of the moon. Later, in the first century BC, Seneca mentioned the possibility of a rotating earth, but did not necessarily believe that it was possible.Philolaus (circa 480 BC - circa 405 BC), was a Greek mathematician and philosopher. He was an immediate pupil and transcriber of Pythagoras. He was the first to propound the doctrine of the motion of the Earth; some attribute this doctrine to Pythagoras, but there is no evidence in support of their view. So says the website.
Read what he had to say, and you'll agree that it's very strange indeed, and not at all a description of the solar system. But at least he said the earth moved.
Anyway, those are the predecessors of the orbiting earth theory. Those ideas seem to have been around in plenty of time for the Enoch text.