Occultation event with (11552) Boucolion, event index number 4248
Regions able to see the event: SAmericaN
Geocentric closest approach at 2026/09/16 06:42:06 UTC
J2000 position of star is 06:37:52.2 +12:22:06
Equinox of date position of star is 06:39:22.1 +12:20:36
Star is 133 degrees from the moon. Moon is 26% illuminated.
Stellar brightness G=14.5, apparent brightess of occulting body is G=16.2
Use an exposure time of 0.45 seconds with the standard RECON-QHY system.
SNR of 9.5 per integration for unocculted signal
Expected flux drop is 83% with SNR of 7.9 for the occulted depth (per occulted point)
Apparent velocity is 19.3 km/sec on the sky relative to the star, or, 16.3 arcsec/hr.
Position angle of asteroid motion is 102.7 degrees
The recommended exposure time corresponds to 8.7 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 31.3 km.
The sky-plane scale is 4269.7 km/arcsec.
Diameter estimates:
57.3 km assuming a 5% albedo, maximum of 3.0 sec for a central chord
23.4 km assuming a 30% albedo, maximum of 1.2 sec for a central chord
Cross-track diameter of 51.1 km used for deployment plan.
Star training set for 11552_Boucolion, (2026/09/16 06:42UT) Object RA Dec mag sep mel Betelgeuse 05:56:37.1 +07:24:35 0.4 11.62 140 Alhena 06:39:15.3 +16:22:27 1.9 4.03 134 PPM 122607 06:33:08.9 +11:46:16 6.3 1.62 134 PPM 122797 06:40:03.0 +12:42:46 7.9 0.41 133 PPM 122810 06:40:33.1 +12:27:44 10.9 0.31 133 11552_Boucolio 06:39:22.1 +12:20:36 16.2 133 Positions are for equinox of date
Star training set for 11552_Boucolion, (2026/09/16 06:42UT) Object RA Dec mag sep mel Betelgeuse 05:55:10.3 +07:24:26 0.4 11.62 140 Alhena 06:37:42.8 +16:23:56 1.9 4.03 134 PPM 122607 06:31:39.4 +11:47:31 6.3 1.62 134 PPM 122797 06:38:33.0 +12:44:18 7.9 0.41 133 PPM 122810 06:39:03.2 +12:29:17 10.9 0.31 133 11552_Boucolio 06:37:52.2 +12:22:06 16.2 133 Positions are for J2000