The interactive map below shows our current prediction for the stellar occultations by (617) Patroclus/Menoetius on 2022 July 28 UT. The prediction is based on a Gaia eDR3 position for the star, corrected for parallax and proper motion, and the v20220709094217 orbit estimate for Patroclus/Menoetius, which uses kernels patroclus_20220708a_5occ1 (barycenter) and pm5_ccloud1 (mutual orbit). This prediction has 1-sigma cross-track uncertainties of 7.5 km and 8.0 km and 1-sigma downtrack uncertainties of 0.4 sec and 0.4 sec for Patroclus and Menoetius, respectively, for this event.
Geocentric mid-time of the event is 16:21:10 UT. The J2000 star position is RA 18:03:34.3 (18.059529), Dec -45:15:11 (-45.252933), and its magnitude is 13.55. Patroclus and Menoetius are moving at 11.4 km/s with respect to the star and their diameters are estimated to be 113 km and 108 km, respectively, for this occultation so central chords are expected to last 9.9 seconds for Patroclus and 9.5 seconds for Menoetius. The system magnitude (Patroclus+Menoetius) is predicted to be 15.0 at event time, so it will be 3.9 times fainter than the star.
Of-date coordinates for the target star on event night are RA 18:05:14.1 (18.087250), Dec -45:15:02 (-45.250556).