Occultation event with (11552) Boucolion, event index number 1729
Regions able to see the event: Australia
Geocentric closest approach at 2025/12/27 16:56:49 UTC
J2000 position of star is 04:22:09.1 +05:06:13
Equinox of date position of star is 04:23:31.9 +05:09:47
Star is 62 degrees from the moon. Moon is 49% illuminated.
Stellar brightness G=16.5, apparent brightess of occulting body is G=15.4
Use an exposure time of 1.10 seconds with the standard RECON-QHY system.
SNR of 3.0 per integration for unocculted signal
Expected flux drop is 26% with SNR of 0.8 for the occulted depth (per occulted point)
Apparent velocity is 14.3 km/sec on the sky relative to the star, or, 15.5 arcsec/hr.
Position angle of asteroid motion is 102.0 degrees
The recommended exposure time corresponds to 15.7 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 30.8 km.
The sky-plane scale is 3324.9 km/arcsec.
Diameter estimates:
57.3 km assuming a 5% albedo, aximum of 4.0 sec for a central chord
23.4 km assuming a 30% albedo, maximum of 1.6 sec for a central chord
Cross-track diameter of 51.1 km used for deployment plan.
Star training set for 11552_Boucolion, (2025/12/27 16:57UT) Object RA Dec mag sep mel Aldebaran 04:37:24.9 +16:33:34 0.8 11.89 65 67Bet Eri 05:09:07.7 -05:03:17 2.8 15.30 74 45 Tau 04:12:43.5 +05:35:19 5.7 2.72 59 PPM 147540 04:27:20.3 +05:12:27 7.6 0.95 62 PPM 147463 04:23:01.0 +05:26:56 9.0 0.31 61 PPM 147473 04:23:43.4 +05:23:30 10.8 0.23 62 11552_Boucolio 04:23:31.9 +05:09:47 15.4 62 Positions are for equinox of date
Star training set for 11552_Boucolion, (2025/12/27 16:57UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 11.89 65 67Bet Eri 05:07:50.8 -05:05:13 2.8 15.30 74 45 Tau 04:11:20.5 +05:31:23 5.7 2.72 59 PPM 147540 04:25:57.5 +05:09:01 7.6 0.95 62 PPM 147463 04:21:38.0 +05:23:21 9.0 0.31 61 PPM 147473 04:22:20.6 +05:19:56 10.8 0.23 62 11552_Boucolio 04:22:09.1 +05:06:13 15.4 62 Positions are for J2000