Occultation event with (1208) Troilus, event index number 1609
Regions able to see the event: SAmericaN,SAfrica
Geocentric closest approach at 2025/11/28 23:40:20 UTC
J2000 position of star is 03:04:28.2 +21:02:17
Equinox of date position of star is 03:05:57.5 +21:08:15
Star is 64 degrees from the moon. Moon is 58% illuminated.
Stellar brightness G=14.7, apparent brightess of occulting body is G=13.8
Use an exposure time of 0.95 seconds with the standard RECON-QHY system.
SNR of 9.8 per integration for unocculted signal
Expected flux drop is 29% with SNR of 2.9 for the occulted depth (per occulted point)
Apparent velocity is 18.8 km/sec on the sky relative to the star, or, 22.8 arcsec/hr.
Position angle of asteroid motion is 95.5 degrees
The recommended exposure time corresponds to 17.9 km per image.
The 1-sigma error in the time of the event is 1.2 seconds.
The 1-sigma cross-track error in the shadow position is 23.4 km.
The sky-plane scale is 2965.4 km/arcsec.
Diameter estimates:
92.9 km assuming a 5% albedo, aximum of 4.9 sec for a central chord
37.9 km assuming a 30% albedo, maximum of 2.0 sec for a central chord
Cross-track diameter of 100.5 km used for deployment plan.
Star training set for 1208_Troilus, (2025/11/28 23:40UT) Object RA Dec mag sep mel Aldebaran 04:37:24.6 +16:33:33 0.8 22.09 84 Hamal 02:08:38.4 +23:35:01 2.0 13.47 53 48Eps Ari 03:00:41.9 +21:26:33 5.6 1.26 63 PPM 092186 03:05:44.7 +21:34:22 8.3 0.44 64 PPM 092188 03:05:53.4 +21:22:05 10.7 0.23 64 1208_Troilus 03:05:57.5 +21:08:15 13.8 64 Positions are for equinox of date
Star training set for 1208_Troilus, (2025/11/28 23:40UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 22.09 84 Hamal 02:07:10.8 +23:27:41 2.0 13.47 53 48Eps Ari 02:59:12.6 +21:20:25 5.6 1.26 63 PPM 092186 03:04:15.2 +21:28:23 8.3 0.44 64 PPM 092188 03:04:24.0 +21:16:06 10.7 0.23 64 1208_Troilus 03:04:28.2 +21:02:17 13.8 64 Positions are for J2000