Comments: Only 3min before clouds got too thick

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Observation 1
Feature(s)	Io
Filter(s)	rgb
Date	2021-09-17 10:15:00
Julian day	2459474.9270833335
System I	220.44°
System II	156.28°
System III	347.79°
Illumination	100.0%
Phase angle	6.199999809265137°
Solar longitude	49.4°
Eq. diameter	47.54″
Derotation	3.0 min