The interactive map below shows our current prediction for the occultation by (617) Patroclus-Menoetius on 2024 August 11 UT. The predicted locations of the shadows of Patroclus and Menoetius are indicated by the blue and green paths, respectively. This prediction is based on a Gaia eDR3 position for the star, corrected for parallax and proper motion, and the v20240531161330 orbit estimate for Patroclus-Menoetius, which is derived from pm_combocloud3_1a_bary.bsp and pm_combocloud3_1a_mutual.bsp. This ephemeris has a 1-sigma crosstrack uncertainty of 4.2 km and a 1-sigma downtrack uncertainty of 2.2 sec for this event.
The geocentric mid-time of the event is 10:47:33.5 UT. The J2000 star position is RA 01:08:10.1 (1.1361398), Dec -13:06:28 (-13.107781), and its magnitude is 13.39. Patroclus and Menoetius are moving at 5.2 km/s with respect to the star and their cross-track sizes are estimated to be 107.4 and 102.5 km, respectively, so central chords are expected to last 20.8 seconds for Patroclus and 19.9 seconds for Menoetius.
At the time of the occultation, the target star will be 147.1 degrees from the (39% illuminated) Moon. The system magnitude (Patroclus+Menoetius) is predicted to be 14.85, so it will be 3.8 times fainter than the star it is occulting.
Of-date coordinates for the target star on event night are RA 01:09:23.5 (1.1565278), Dec -12:58:37 (-12.976944).