value	quality	siderealorsynodic	author	ref	method
21.7860	2	Sidereal	Durech	2023A&A...675A..24D	Model
21.7998	2	Synodic	Pal	2020ApJS..247...26P	Lightcurve
21.8070	2	Synodic	Waszczak	2015AJ....150...75W	Lightcurve