value quality siderealorsynodic author ref method 17.3854 2 Sidereal Durech 2020A&A...643A..59D Model 17.3860 3 Synodic Pilcher 2010MPBu...37..119P Lightcurve 17.3863 2 Sidereal Durech 2023A&A...675A..24D Model