Occultation event with (9142) Rhesus, event index number 5079
Regions able to see the event: SAmericaN
Geocentric closest approach at 2026/12/06 22:48:55 UTC
J2000 position of star is 05:03:33.1 +08:26:36
Equinox of date position of star is 05:05:01.1 +08:28:46
Star is 149 degrees from the moon. Moon is 4% illuminated.
Stellar brightness G=16.6, apparent brightess of occulting body is G=15.7
Use an exposure time of 1.15 seconds with the standard RECON-QHY system.
SNR of 3.1 per integration for unocculted signal
Expected flux drop is 31% with SNR of 1.0 for the occulted depth (per occulted point)
Apparent velocity is 17.9 km/sec on the sky relative to the star, or, 20.0 arcsec/hr.
Position angle of asteroid motion is 87.8 degrees
The recommended exposure time corresponds to 20.6 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 28.4 km.
The sky-plane scale is 3229.7 km/arcsec.
Diameter estimates:
43.7 km assuming a 5% albedo, maximum of 2.4 sec for a central chord
17.8 km assuming a 30% albedo, maximum of 1.0 sec for a central chord
Cross-track diameter of 42.3 km used for deployment plan.
Star training set for 9142_Rhesus, (2026/12/06 22:49UT) Object RA Dec mag sep mel Aldebaran 04:37:28.2 +16:33:40 0.8 10.51 159 Bellatrix 05:26:34.6 +06:22:19 1.6 5.74 144 14 Ori 05:09:21.0 +08:31:53 5.7 1.07 149 PPM 148427 05:07:02.6 +08:30:14 8.3 0.50 149 PPM 148388 05:05:30.2 +08:23:52 9.3 0.14 149 9142_Rhesus 05:05:01.1 +08:28:46 15.7 149 Positions are for equinox of date
Star training set for 9142_Rhesus, (2026/12/06 22:49UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 10.51 159 Bellatrix 05:25:07.8 +06:20:58 1.6 5.74 144 14 Ori 05:07:52.9 +08:29:53 5.7 1.07 149 PPM 148427 05:05:34.6 +08:28:09 8.3 0.50 149 PPM 148388 05:04:02.2 +08:21:43 9.3 0.14 149 9142_Rhesus 05:03:33.1 +08:26:36 15.7 149 Positions are for J2000