Occultation event with (2357) Phereclos, event index number 4020
Regions able to see the event: SAmericaN
Geocentric closest approach at 2026/08/16 08:27:01 UTC
J2000 position of star is 05:07:38.6 +20:32:26
Equinox of date position of star is 05:09:13.5 +20:34:25
Star is 112 degrees from the moon. Moon is 16% illuminated.
Stellar brightness G=16.8, apparent brightess of occulting body is G=14.9
Use an exposure time of 1.90 seconds with the standard RECON-QHY system.
SNR of 3.0 per integration for unocculted signal
Expected flux drop is 15% with SNR of 0.5 for the occulted depth (per occulted point)
Apparent velocity is 24.2 km/sec on the sky relative to the star, or, 20.7 arcsec/hr.
Position angle of asteroid motion is 87.7 degrees
The recommended exposure time corresponds to 46.1 km per image.
The 1-sigma error in the time of the event is 0.2 seconds.
The 1-sigma cross-track error in the shadow position is 33.7 km.
The sky-plane scale is 4211.7 km/arcsec.
Diameter estimates:
95.9 km assuming a 5% albedo, maximum of 4.0 sec for a central chord
39.2 km assuming a 30% albedo, maximum of 1.6 sec for a central chord
Cross-track diameter of 94.6 km used for deployment plan.
Star training set for 2357_Phereclos, (2026/08/16 08:27UT) Object RA Dec mag sep mel Aldebaran 04:37:27.1 +16:33:38 0.8 8.53 120 Alnath 05:27:58.6 +28:37:38 1.6 9.11 108 102Iot Tau 05:04:41.4 +21:37:32 4.6 1.49 113 PPM 094109 05:10:47.4 +20:29:24 8.2 0.38 112 PPM 094088 05:09:41.0 +20:24:42 10.7 0.19 112 2357_Phereclos 05:09:13.5 +20:34:25 14.9 112 Positions are for equinox of date
Star training set for 2357_Phereclos, (2026/08/16 08:27UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 8.53 120 Alnath 05:26:17.6 +28:36:22 1.6 9.11 108 102Iot Tau 05:03:05.9 +21:35:23 4.6 1.49 113 PPM 094109 05:09:12.6 +20:27:28 8.2 0.38 112 PPM 094088 05:08:06.2 +20:22:44 10.7 0.19 112 2357_Phereclos 05:07:38.6 +20:32:26 14.9 112 Positions are for J2000