Occultation event with (2357) Phereclos, event index number 4975
Regions able to see the event: SAmericaN
Geocentric closest approach at 2026/12/01 06:31:36 UTC
J2000 position of star is 05:07:51.9 +19:43:13
Equinox of date position of star is 05:09:27.3 +19:45:13
Star is 81 degrees from the moon. Moon is 50% illuminated.
Stellar brightness G=15.1, apparent brightess of occulting body is G=13.9
Use an exposure time of 1.35 seconds with the standard RECON-QHY system.
SNR of 8.7 per integration for unocculted signal
Expected flux drop is 25% with SNR of 2.2 for the occulted depth (per occulted point)
Apparent velocity is 17.4 km/sec on the sky relative to the star, or, 19.3 arcsec/hr.
Position angle of asteroid motion is 83.7 degrees
The recommended exposure time corresponds to 23.5 km per image.
The 1-sigma error in the time of the event is 0.4 seconds.
The 1-sigma cross-track error in the shadow position is 34.0 km.
The sky-plane scale is 3257.4 km/arcsec.
Diameter estimates:
95.9 km assuming a 5% albedo, maximum of 5.5 sec for a central chord
39.2 km assuming a 30% albedo, maximum of 2.2 sec for a central chord
Cross-track diameter of 94.6 km used for deployment plan.
Star training set for 2357_Phereclos, (2026/12/01 06:32UT) Object RA Dec mag sep mel Aldebaran 04:37:28.1 +16:33:40 0.8 8.24 89 Alnath 05:27:59.7 +28:37:39 1.6 9.83 77 104 Tau 05:09:02.5 +18:40:44 5.6 1.08 82 PPM 120643 05:10:25.9 +19:53:33 7.4 0.27 81 2357_Phereclos 05:09:27.3 +19:45:13 13.9 81 Positions are for equinox of date
Star training set for 2357_Phereclos, (2026/12/01 06:32UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 8.24 89 Alnath 05:26:17.6 +28:36:22 1.6 9.83 77 104 Tau 05:07:27.9 +18:38:44 5.6 1.08 82 PPM 120643 05:08:50.4 +19:51:35 7.4 0.27 81 2357_Phereclos 05:07:51.9 +19:43:13 13.9 81 Positions are for J2000