value quality siderealorsynodic author ref method 6.2930 2 Synodic Wisniewski 1997Icar..126..395W Lightcurve 6.7589 2 Sidereal Durech 2023A&A...675A..24D Model 6.7620 2 Synodic Waszczak 2015AJ....150...75W Lightcurve