value quality siderealorsynodic author ref method 7.6685 2 Sidereal Durech 2023A&A...675A..24D Model 7.6688 2 Synodic Pal 2020ApJS..247...26P Lightcurve 7.6690 2 Synodic Waszczak 2015AJ....150...75W Lightcurve