value quality siderealorsynodic author ref method 9.7640 3 Synodic Angeli 1996P&SS...44..181A Lightcurve 9.7688 2 Sidereal Durech 2020A&A...643A..59D Model 9.7689 2 Sidereal Durech 2023A&A...675A..24D Model