Occultation event with (1208) Troilus, event index number 4117
Regions able to see the event: Europe
Geocentric closest approach at 2026/08/29 02:41:35 UTC
J2000 position of star is 05:30:02.8 +37:57:33
Equinox of date position of star is 05:31:52.3 +37:58:41
Star is 96 degrees from the moon. Moon is 99% illuminated.
Stellar brightness G=16.3, apparent brightess of occulting body is G=14.8
Use an exposure time of 1.00 seconds with the standard RECON-QHY system.
SNR of 3.2 per integration for unocculted signal
Expected flux drop is 20% with SNR of 0.6 for the occulted depth (per occulted point)
Apparent velocity is 24.0 km/sec on the sky relative to the star, or, 21.9 arcsec/hr.
Position angle of asteroid motion is 53.8 degrees
The recommended exposure time corresponds to 24.0 km per image.
The 1-sigma error in the time of the event is 1.3 seconds.
The 1-sigma cross-track error in the shadow position is 12.9 km.
The sky-plane scale is 3949.2 km/arcsec.
Diameter estimates:
92.9 km assuming a 5% albedo, maximum of 3.9 sec for a central chord
37.9 km assuming a 30% albedo, maximum of 1.6 sec for a central chord
Cross-track diameter of 100.5 km used for deployment plan.
Star training set for 1208_Troilus, (2026/08/29 02:42UT) Object RA Dec mag sep mel Aldebaran 04:37:27.2 +16:33:39 0.8 24.53 83 3Iot Aur 04:58:44.0 +33:12:21 2.7 8.25 89 21Sig Aur 05:26:28.1 +37:24:27 6.4 1.21 95 PPM 070335 05:27:28.0 +38:03:58 8.2 0.87 95 PPM 070456 05:31:34.8 +37:57:09 9.2 0.06 96 1208_Troilus 05:31:52.3 +37:58:41 14.8 97 Positions are for equinox of date
Star training set for 1208_Troilus, (2026/08/29 02:42UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 24.53 83 3Iot Aur 04:56:59.6 +33:09:57 2.7 8.25 89 21Sig Aur 05:24:39.2 +37:23:07 6.4 1.21 95 PPM 070335 05:25:38.5 +38:02:41 8.2 0.87 95 PPM 070456 05:29:45.3 +37:56:01 9.2 0.06 96 1208_Troilus 05:30:02.8 +37:57:33 14.8 96 Positions are for J2000