Occultation event with (9799) Thronium, event index number 3794
Regions able to see the event: NMexico,SMexico
Geocentric closest approach at 2026/06/15 02:41:48 UTC
J2000 position of star is 10:18:29.0 -21:56:23
Equinox of date position of star is 10:19:44.3 -22:04:22
Star is 85 degrees from the moon. Moon is 0% illuminated.
Stellar brightness G=15.2, apparent brightess of occulting body is G=15.5
Use an exposure time of 0.75 seconds with the standard RECON-QHY system.
SNR of 7.6 per integration for unocculted signal
Expected flux drop is 57% with SNR of 4.4 for the occulted depth (per occulted point)
Apparent velocity is 21.6 km/sec on the sky relative to the star, or, 19.6 arcsec/hr.
Position angle of asteroid motion is 73.6 degrees
The recommended exposure time corresponds to 16.2 km per image.
The 1-sigma error in the time of the event is 0.3 seconds.
The 1-sigma cross-track error in the shadow position is 33.1 km.
The sky-plane scale is 3953.6 km/arcsec.
Diameter estimates:
71.1 km assuming a 5% albedo, maximum of 3.3 sec for a central chord
29.0 km assuming a 30% albedo, maximum of 1.3 sec for a central chord
Cross-track diameter of 68.0 km used for deployment plan.
Star training set for 9799_Thronium, (2026/06/15 02:42UT) Object RA Dec mag sep mel Regulus 10:09:46.7 +11:50:13 1.3 34.00 66 Alphard 09:28:53.2 -08:46:28 2.0 18.06 68 PPM 257554 10:22:43.5 -23:50:41 6.5 1.90 87 PPM 257500 10:20:21.0 -22:06:05 8.3 0.14 85 9799_Thronium 10:19:44.3 -22:04:22 15.5 85 Positions are for equinox of date
Star training set for 9799_Thronium, (2026/06/15 02:42UT) Object RA Dec mag sep mel Regulus 10:08:21.9 +11:58:02 1.3 34.00 66 Alphard 09:27:35.2 -08:39:30 2.0 18.06 68 PPM 257554 10:21:28.6 -23:42:39 6.5 1.90 87 PPM 257500 10:19:05.8 -21:58:05 8.3 0.14 85 9799_Thronium 10:18:29.0 -21:56:23 15.5 85 Positions are for J2000