Putting the astronomy back into Greek calendrics: the parapegma of Euktemon

TL;DR

This paper re-examines Euktemon's parapegma, suggesting that some star observations were likely calculated based on time rather than direct observation, blending astronomy with Greek calendric practices.

Contribution

It introduces a new perspective that some ancient star observations in Greek calendrics were based on calculations, not just direct observations.

Findings

Star observations may have been calculated, not observed.

The method aligns with Pliny's description of solar positioning.

Reinterprets ancient Greek calendric data in an astronomical context.

Abstract

A re-investigation of the parapegma of Euktemon (5th century BC, Athens), based on the assumption that some star observations may in fact have been calculated rather than directly observed. The calculation follows Pliny, Natural History 18.218, where he states that the sun should be at least three-quarters of an hour below the horizon. So 'observations' were based on time, rather than on star magnitude.