value quality siderealorsynodic author ref method 5.9470 2- Synodic Erasmus 2020ApJS..247...13E Lightcurve 6.7860 2 Synodic Waszczak 2015AJ....150...75W Lightcurve 6.7901 2 Sidereal Durech 2023A&A...675A..24D Model