Occultation event with (2357) Phereclos, event index number 4101
Regions able to see the event: SAmericaN
Geocentric closest approach at 2026/08/26 05:06:58 UTC
J2000 position of star is 05:13:02.9 +20:34:38
Equinox of date position of star is 05:14:38.0 +20:36:24
Star is 129 degrees from the moon. Moon is 96% illuminated.
Stellar brightness G=15.9, apparent brightess of occulting body is G=14.9
Use an exposure time of 1.15 seconds with the standard RECON-QHY system.
SNR of 5.0 per integration for unocculted signal
Expected flux drop is 29% with SNR of 1.4 for the occulted depth (per occulted point)
Apparent velocity is 20.2 km/sec on the sky relative to the star, or, 17.7 arcsec/hr.
Position angle of asteroid motion is 89.0 degrees
The recommended exposure time corresponds to 23.3 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 33.9 km.
The sky-plane scale is 4106.7 km/arcsec.
Diameter estimates:
95.9 km assuming a 5% albedo, maximum of 4.7 sec for a central chord
39.2 km assuming a 30% albedo, maximum of 1.9 sec for a central chord
Cross-track diameter of 94.6 km used for deployment plan.
Star training set for 2357_Phereclos, (2026/08/26 05:07UT) Object RA Dec mag sep mel Aldebaran 04:37:27.2 +16:33:38 0.8 9.69 119 Alnath 05:27:58.7 +28:37:39 1.6 8.57 132 108 Tau 05:17:03.9 +22:18:46 6.2 1.80 129 PPM 094144 05:12:22.6 +20:36:01 8.2 0.53 128 PPM 094197 05:16:24.8 +20:54:31 9.7 0.51 129 PPM 094180 05:15:05.3 +20:40:12 10.7 0.12 129 2357_Phereclos 05:14:38.0 +20:36:24 14.9 129 Positions are for equinox of date
Star training set for 2357_Phereclos, (2026/08/26 05:07UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 9.69 119 Alnath 05:26:17.6 +28:36:22 1.6 8.57 132 108 Tau 05:15:27.6 +22:17:05 6.2 1.80 129 PPM 094144 05:10:47.6 +20:34:09 8.2 0.53 128 PPM 094197 05:14:49.6 +20:52:48 9.7 0.51 129 PPM 094180 05:13:30.2 +20:38:26 10.7 0.12 129 2357_Phereclos 05:13:02.9 +20:34:38 14.9 129 Positions are for J2000