The interactive map below shows our current prediction for the occultation by (617) Patroclus-Menoetius on 2026 January 4 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 v20251216162817 orbit estimate for Patroclus-Menoetius, which is derived from pmcombo5_cloud2b_bary.bsp and pmcombo5_cloud2b_mutual.bsp. This ephemeris has a 1-sigma crosstrack uncertainty of 9.1 km and a 1-sigma downtrack uncertainty of 1.0 sec for this event.
The geocentric mid-time of the event is 22:36:56.0 UT. The J2000 star position is RA 02:28:49.3 (2.4803550), Dec +18:01:55 (18.031918), and its magnitude is 11.91. Patroclus-Menoetius is moving at 3.9 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 27.5 seconds for Patroclus and 26.2 seconds for Menoetius.
At the time of the occultation, the target star will be 84.5 degrees from the (97% illuminated) Moon. The system magnitude (Patroclus+Menoetius) is predicted to be 15.18, so it will be 20 times fainter than the star it is occulting.
Of-date coordinates for the target star on event night are RA 02:30:16.2 (2.5045000), Dec +18:08:49 (18.146944).