Occultation event with (1208) Troilus, event index number 5166
Regions able to see the event: Senegal,SMexico
Geocentric closest approach at 2026/12/11 02:12:42 UTC
J2000 position of star is 05:12:41.3 +46:47:12
Equinox of date position of star is 05:14:41.7 +46:49:00
Star is 152 degrees from the moon. Moon is 4% illuminated.
Stellar brightness G=14.1, apparent brightess of occulting body is G=14.1
Use an exposure time of 0.35 seconds with the standard RECON-QHY system.
SNR of 9.5 per integration for unocculted signal
Expected flux drop is 50% with SNR of 4.8 for the occulted depth (per occulted point)
Apparent velocity is 19.9 km/sec on the sky relative to the star, or, 22.6 arcsec/hr.
Position angle of asteroid motion is 103.4 degrees
The recommended exposure time corresponds to 7.0 km per image.
The 1-sigma error in the time of the event is 0.6 seconds.
The 1-sigma cross-track error in the shadow position is 32.0 km.
The sky-plane scale is 3177.3 km/arcsec.
Diameter estimates:
92.9 km assuming a 5% albedo, maximum of 4.7 sec for a central chord
37.9 km assuming a 30% albedo, maximum of 1.9 sec for a central chord
Cross-track diameter of 100.5 km used for deployment plan.
Star training set for 1208_Troilus, (2026/12/11 02:13UT) Object RA Dec mag sep mel Aldebaran 04:37:28.2 +16:33:41 0.8 31.22 147 34Bet Aur 06:01:30.4 +44:56:50 1.9 8.35 159 PPM 047798 05:12:43.6 +46:59:33 6.0 0.38 151 PPM 047852 05:15:09.2 +46:52:53 8.5 0.10 152 1208_Troilus 05:14:41.7 +46:49:00 14.1 152 Positions are for equinox of date
Star training set for 1208_Troilus, (2026/12/11 02:13UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 31.22 147 34Bet Aur 05:59:31.6 +44:56:51 1.9 8.35 159 PPM 047798 05:10:43.1 +46:57:40 6.0 0.38 151 PPM 047852 05:13:08.7 +46:51:05 8.5 0.10 152 1208_Troilus 05:12:41.3 +46:47:12 14.1 152 Positions are for J2000