Occultation event with (1208) Troilus, event index number 4523
Regions able to see the event: Australia
Geocentric closest approach at 2026/10/30 17:11:57 UTC
J2000 position of star is 05:40:21.2 +43:53:59
Equinox of date position of star is 05:42:18.1 +43:54:43
Star is 21 degrees from the moon. Moon is 74% illuminated.
Stellar brightness G=15.0, apparent brightess of occulting body is G=14.4
Use an exposure time of 1.15 seconds with the standard RECON-QHY system.
SNR of 10.0 per integration for unocculted signal
Expected flux drop is 37% with SNR of 3.7 for the occulted depth (per occulted point)
Apparent velocity is 16.0 km/sec on the sky relative to the star, or, 17.2 arcsec/hr.
Position angle of asteroid motion is 145.3 degrees
The recommended exposure time corresponds to 18.4 km per image.
The 1-sigma error in the time of the event is 1.0 seconds.
The 1-sigma cross-track error in the shadow position is 29.9 km.
The sky-plane scale is 3338.3 km/arcsec.
Diameter estimates:
92.9 km assuming a 5% albedo, maximum of 5.8 sec for a central chord
37.9 km assuming a 30% albedo, maximum of 2.4 sec for a central chord
Cross-track diameter of 100.5 km used for deployment plan.
Star training set for 1208_Troilus, (2026/10/30 17:12UT) Object RA Dec mag sep mel Pollux 07:46:57.3 +27:57:33 1.1 29.58 14 34Bet Aur 06:01:29.9 +44:56:50 1.9 3.58 20 PPM 048445 05:49:10.0 +42:32:02 6.3 1.86 19 PPM 048331 05:41:19.3 +43:43:20 8.3 0.26 21 PPM 048340 05:42:17.4 +43:44:35 8.7 0.17 21 1208_Troilus 05:42:18.1 +43:54:43 14.4 21 Positions are for equinox of date
Star training set for 1208_Troilus, (2026/10/30 17:12UT) Object RA Dec mag sep mel Pollux 07:45:17.7 +28:01:33 1.1 29.58 14 34Bet Aur 05:59:31.6 +44:56:51 1.9 3.58 20 PPM 048445 05:47:14.7 +42:31:34 6.3 1.86 19 PPM 048331 05:39:22.6 +43:42:34 8.3 0.26 21 PPM 048340 05:40:20.7 +43:43:51 8.7 0.17 21 1208_Troilus 05:40:21.2 +43:53:59 14.4 21 Positions are for J2000