value quality siderealorsynodic author ref method 7.8500 2+ Synodic Behrend LCDB Lightcurve 7.9319 2 Sidereal Durech 2016A&A...587A..48D Model 7.9319 2 Sidereal Hanus 2016A&A...586A.108H Model 7.9320 3 Synodic Higgins LCDB Lightcurve