value quality siderealorsynodic author ref method 177.1300 2 Sidereal Durech 2020A&A...643A..59D Model 178.0000 3 Synodic Pilcher 2014MPBu...41...71P Lightcurve 8.9000 1 Synodic Lagerkvist 1978A&AS...31..361L Lightcurve