Occultation event with (11552) Boucolion, event index number 4200
Regions able to see the event: Australia
Geocentric closest approach at 2026/09/07 19:26:05 UTC
J2000 position of star is 06:33:52.5 +12:33:55
Equinox of date position of star is 06:35:22.4 +12:32:34
Star is 27 degrees from the moon. Moon is 14% illuminated.
Stellar brightness G=15.9, apparent brightess of occulting body is G=16.2
Use an exposure time of 0.55 seconds with the standard RECON-QHY system.
SNR of 3.4 per integration for unocculted signal
Expected flux drop is 57% with SNR of 1.9 for the occulted depth (per occulted point)
Apparent velocity is 22.9 km/sec on the sky relative to the star, or, 18.9 arcsec/hr.
Position angle of asteroid motion is 100.3 degrees
The recommended exposure time corresponds to 12.6 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 30.1 km.
The sky-plane scale is 4354.5 km/arcsec.
Diameter estimates:
57.3 km assuming a 5% albedo, maximum of 2.5 sec for a central chord
23.4 km assuming a 30% albedo, maximum of 1.0 sec for a central chord
Cross-track diameter of 51.1 km used for deployment plan.
Star training set for 11552_Boucolion, (2026/09/07 19:26UT) Object RA Dec mag sep mel Betelgeuse 05:56:37.0 +07:24:35 0.4 10.83 37 Alhena 06:39:15.2 +16:22:27 1.9 3.94 24 PPM 122607 06:33:08.8 +11:46:16 6.3 0.94 27 PPM 122725 06:37:01.6 +13:12:01 7.7 0.77 26 PPM 122682 06:35:26.8 +12:41:58 10.0 0.16 26 11552_Boucolio 06:35:22.4 +12:32:34 16.2 26 Positions are for equinox of date
Star training set for 11552_Boucolion, (2026/09/07 19:26UT) Object RA Dec mag sep mel Betelgeuse 05:55:10.3 +07:24:26 0.4 10.83 37 Alhena 06:37:42.8 +16:23:56 1.9 3.94 24 PPM 122607 06:31:39.4 +11:47:31 6.3 0.94 27 PPM 122725 06:35:31.3 +13:13:26 7.7 0.77 26 PPM 122682 06:33:56.8 +12:43:19 10.0 0.16 26 11552_Boucolio 06:33:52.5 +12:33:55 16.2 27 Positions are for J2000