Occultation event with (2357) Phereclos, event index number 5027
Regions able to see the event: Australia
Geocentric closest approach at 2026/12/04 12:36:58 UTC
J2000 position of star is 05:06:05.2 +19:40:29
Equinox of date position of star is 05:07:40.5 +19:42:32
Star is 124 degrees from the moon. Moon is 19% illuminated.
Stellar brightness G=13.2, apparent brightess of occulting body is G=13.9
Use an exposure time of 0.13 seconds with the standard RECON-QHY system.
SNR of 9.7 per integration for unocculted signal
Expected flux drop is 66% with SNR of 6.4 for the occulted depth (per occulted point)
Apparent velocity is 17.7 km/sec on the sky relative to the star, or, 19.6 arcsec/hr.
Position angle of asteroid motion is 83.8 degrees
The recommended exposure time corresponds to 2.3 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 3252.9 km/arcsec.
Diameter estimates:
95.9 km assuming a 5% albedo, maximum of 5.4 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, (2026/12/04 12:37UT) Object RA Dec mag sep mel Aldebaran 04:37:28.1 +16:33:40 0.8 7.83 131 Alnath 05:27:59.8 +28:37:39 1.6 10.05 119 104 Tau 05:09:02.6 +18:40:44 5.6 1.08 124 PPM 120582 05:07:07.5 +19:50:29 6.7 0.19 124 2357_Phereclos 05:07:40.5 +19:42:32 13.9 124 Positions are for equinox of date
Star training set for 2357_Phereclos, (2026/12/04 12:37UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 7.83 131 Alnath 05:26:17.6 +28:36:22 1.6 10.05 119 104 Tau 05:07:27.9 +18:38:44 5.6 1.08 124 PPM 120582 05:05:32.1 +19:48:24 6.7 0.19 124 2357_Phereclos 05:06:05.2 +19:40:29 13.9 124 Positions are for J2000