value quality siderealorsynodic author ref method 2.8896 2 Synodic Pal 2020ApJS..247...26P Lightcurve 2.8900 2+ Synodic Ferrero 2012MPBu...39..138F Lightcurve 2.8900 2+ Synodic Strabla 2012MPBu...39..177S Lightcurve