Occultation event with (5638) Deikoon, event index number 1532
Regions able to see the event: SAmericaN
Geocentric closest approach at 2025/11/18 03:47:53 UTC
J2000 position of star is 01:30:26.6 -01:12:20
Equinox of date position of star is 01:31:45.9 -01:04:22
Star is 162 degrees from the moon. Moon is 4% illuminated.
Stellar brightness G=16.5, apparent brightess of occulting body is G=16.0
Use an exposure time of 1.05 seconds with the standard RECON-QHY system.
SNR of 3.0 per integration for unocculted signal
Expected flux drop is 38% with SNR of 1.1 for the occulted depth (per occulted point)
Apparent velocity is 12.5 km/sec on the sky relative to the star, or, 13.0 arcsec/hr.
Position angle of asteroid motion is 74.5 degrees
The recommended exposure time corresponds to 13.1 km per image.
The 1-sigma error in the time of the event is 1.2 seconds.
The 1-sigma cross-track error in the shadow position is 26.3 km.
The sky-plane scale is 3474.1 km/arcsec.
Diameter estimates:
46.3 km assuming a 5% albedo, aximum of 3.7 sec for a central chord
18.9 km assuming a 30% albedo, maximum of 1.5 sec for a central chord
Cross-track diameter of 41.5 km used for deployment plan.
Star training set for 5638_Deikoon, (2025/11/18 03:48UT) Object RA Dec mag sep mel Fomalhaut 22:59:04.5 -29:29:04 1.2 46.10 117 68Omi Cet 02:20:39.4 -02:51:41 2.0 12.35 160 PPM 183408 01:26:07.7 -02:42:53 6.1 2.16 159 PPM 183605 01:36:05.6 -01:54:09 7.6 1.36 161 PPM 174919 01:32:19.8 -00:48:23 9.9 0.30 162 5638_Deikoon 01:31:45.9 -01:04:22 16.0 162 Positions are for equinox of date
Star training set for 5638_Deikoon, (2025/11/18 03:48UT) Object RA Dec mag sep mel Fomalhaut 22:57:39.7 -29:37:24 1.2 46.10 117 68Omi Cet 02:19:20.8 -02:58:46 2.0 12.35 160 PPM 183408 01:24:48.7 -02:50:56 6.1 2.16 159 PPM 183605 01:34:46.5 -02:02:03 7.6 1.36 161 PPM 174919 01:31:00.4 -00:56:21 9.9 0.30 162 5638_Deikoon 01:30:26.6 -01:12:20 16.0 162 Positions are for J2000