value quality siderealorsynodic author ref method 2.7300 3- Synodic Megna LCDB Lightcurve 2.7425 2+ Synodic Ditteon 2011MPBu...38..214D Lightcurve 2.9080 2+ Synodic Aymami 2011MPBu...38..158A Lightcurve