The parallelism of the solar rays

The concept of parallel rays and divergent rays, in relation to the light source, is necessary to validate hypothesis 2 of Eratosthenes.

 Aim:

validate hypothesis 2 of Eratosthenes

Observation 

Observe the parallelism of the shadows of lined up gnomons.

Production

Draw the sunrays and edit a Gif animated, 

Parallelism of the solar rays (for a distant source)  2019 photos

2021 photos

https://www.geogebra.org/material/iframe/id/che2kbmh

2022 photos (Athens, Bizerte, Malovat, Aigio, Busteni, Pogana)

2023 photos (Serres, Aydin, Aigio, Busteni, Pogana)

2024 photos (Larissa, Aigio)