[Add observation]

Observation 1
Feature(s)	Ganymede shadow transit
Filter(s)	l
Date	2025-12-30 22:57:00
Julian day	2461040.45625
System I	14.291959°
System II	260.39572°
System III	147.85008°
Illumination	100.0%
Phase angle	2.4000000953674316°
Solar longitude	188.7°
Eq. diameter	46.34″
Derotation	6.0 min