Along documenting polar ice and the midnight sun that does not set in the far north on the summer Solstice, Pytheus also reported that the moon caused the tides.
The link between tides and the moon was first theorized by Seleucus of Seleucia in the 2nd century. He speculated that the tides were caused by the motions of the moon.
Seleucus of Seleucia, the Babylonian astronomer wrote that the rising and falling of tides were the result of the attractions of the moon and that the height of the tides depends on the location of the moon relative to the sun.
Born in the Babylonian town of Seleucia, he is today primarily remembered as the only known supporter of Aristarchus's heliocentric theory, maintaining that it accurately described the physical structure of the universe.
According to Plutarch, Seleucus was the first to prove the heliocentric system through reasoning, but it is not known what arguments he used. Seleucus’ arguments for a heliocentric theory were probably related to the phenomenon of tides.
Seleucus of Seleucia: Discovery of tides being caused by the moon
