Occultation event with (11552) Boucolion, event index number 5193
Regions able to see the event: Europe
Geocentric closest approach at 2026/12/13 00:07:50 UTC
J2000 position of star is 06:33:57.3 +11:09:08
Equinox of date position of star is 06:35:27.2 +11:07:47
Star is 151 degrees from the moon. Moon is 13% illuminated.
Stellar brightness G=15.7, apparent brightess of occulting body is G=15.5
Use an exposure time of 0.70 seconds with the standard RECON-QHY system.
SNR of 4.4 per integration for unocculted signal
Expected flux drop is 44% with SNR of 1.9 for the occulted depth (per occulted point)
Apparent velocity is 17.4 km/sec on the sky relative to the star, or, 17.9 arcsec/hr.
Position angle of asteroid motion is 95.0 degrees
The recommended exposure time corresponds to 12.2 km per image.
The 1-sigma error in the time of the event is 0.1 seconds.
The 1-sigma cross-track error in the shadow position is 31.6 km.
The sky-plane scale is 3512.2 km/arcsec.
Diameter estimates:
57.3 km assuming a 5% albedo, maximum of 3.3 sec for a central chord
23.4 km assuming a 30% albedo, maximum of 1.3 sec for a central chord
Cross-track diameter of 51.1 km used for deployment plan.
Star training set for 11552_Boucolion, (2026/12/13 00:08UT) Object RA Dec mag sep mel Betelgeuse 05:56:37.9 +07:24:35 0.4 10.27 141 Alhena 06:39:16.1 +16:22:26 1.9 5.33 154 PPM 122614 06:33:18.4 +11:31:23 5.4 0.66 151 PPM 122714 06:36:30.2 +11:06:03 8.0 0.26 152 PPM 122674 06:35:13.5 +11:12:35 9.4 0.10 151 11552_Boucolio 06:35:27.2 +11:07:47 15.5 152 Positions are for equinox of date
Star training set for 11552_Boucolion, (2026/12/13 00:08UT) Object RA Dec mag sep mel Betelgeuse 05:55:10.3 +07:24:26 0.4 10.27 141 Alhena 06:37:42.8 +16:23:56 1.9 5.33 154 PPM 122614 06:31:48.3 +11:32:40 5.4 0.66 151 PPM 122714 06:35:00.4 +11:07:27 8.0 0.26 152 PPM 122674 06:33:43.6 +11:13:56 9.4 0.10 151 11552_Boucolio 06:33:57.3 +11:09:08 15.5 151 Positions are for J2000