[Add observation]

Observation 1
Feature(s)	GRS Oval BA Io
Filter(s)	ch4
Date	2020-07-21 10:10:24
Julian day	2459051.923611111
System I	102.232086°
System II	40.797806°
System III	119.310555°
Illumination	100.0%
Phase angle	1.399999976158142°
Solar longitude	12.4°
Eq. diameter	47.51″
Derotation	14.0 min