Comments: This image features Ganymede, it's shadow and the GRS.

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Observation 1
Feature(s)	Ganymede shadow GRS
Filter(s)	rgb
Date	2017-04-22 04:15:12
Julian day	2457865.6770833335
System I	269.58°
System II	259.23°
System III	22.18°
Illumination	100.0%
Phase angle	2.9000000953674316°
Solar longitude	278.8°
Eq. diameter	43.94″
Derotation	0.0 min