Sosigenes

• Sosigenes was an Astronomer at Alexandria, Egypt, who advised Julius Caesar on the creation of the Julian Calendar in 45 BCE.
• He was the author of 3 Treatises on the Calendar, all now lost.

History

• He is mentioned by Pliny the Elder (23-79 CE) as having agreed with Babylonian astronomy, that the planet Mercury is never more than 22° from the Sun.
• Nothing is known of Sosigenes, other than what Pliny has written about him.