Occultation event with (9799) Thronium, event index number 3768
Regions able to see the event: Australia
Geocentric closest approach at 2026/05/29 14:54:00 UTC
J2000 position of star is 10:10:46.4 -22:44:53
Equinox of date position of star is 10:12:00.8 -22:52:44
Star is 66 degrees from the moon. Moon is 97% illuminated.
Stellar brightness G=15.2, apparent brightess of occulting body is G=15.4
Use an exposure time of 0.95 seconds with the standard RECON-QHY system.
SNR of 8.5 per integration for unocculted signal
Expected flux drop is 54% with SNR of 4.6 for the occulted depth (per occulted point)
Apparent velocity is 17.1 km/sec on the sky relative to the star, or, 16.2 arcsec/hr.
Position angle of asteroid motion is 55.8 degrees
The recommended exposure time corresponds to 16.2 km per image.
The 1-sigma error in the time of the event is 0.2 seconds.
The 1-sigma cross-track error in the shadow position is 34.0 km.
The sky-plane scale is 3794.7 km/arcsec.
Diameter estimates:
71.1 km assuming a 5% albedo, maximum of 4.2 sec for a central chord
29.0 km assuming a 30% albedo, maximum of 1.7 sec for a central chord
Cross-track diameter of 68.0 km used for deployment plan.
Star training set for 9799_Thronium, (2026/05/29 14:54UT) Object RA Dec mag sep mel Regulus 10:09:46.5 +11:50:14 1.3 34.72 79 Alphard 09:28:53.1 -08:46:28 2.0 17.49 81 PPM 257378 10:15:23.2 -23:56:44 6.1 1.32 65 PPM 257332 10:13:05.8 -22:45:44 8.5 0.28 66 PPM 257302 10:11:38.8 -22:54:25 9.5 0.09 66 9799_Thronium 10:12:00.8 -22:52:44 15.4 66 Positions are for equinox of date
Star training set for 9799_Thronium, (2026/05/29 14:54UT) Object RA Dec mag sep mel Regulus 10:08:21.9 +11:58:02 1.3 34.72 79 Alphard 09:27:35.2 -08:39:30 2.0 17.49 81 PPM 257378 10:14:08.9 -23:48:49 6.1 1.32 65 PPM 257332 10:11:51.3 -22:37:52 8.5 0.28 66 PPM 257302 10:10:24.4 -22:46:35 9.5 0.09 66 9799_Thronium 10:10:46.4 -22:44:53 15.4 66 Positions are for J2000