Occultation event with (9799) Thronium, event index number 808
Regions able to see the event: SAmericaS
Geocentric closest approach at 2025/03/13 05:44:34 UTC
J2000 position of star is 08:15:07.9 -11:51:58
Equinox of date position of star is 08:16:19.5 -11:56:40
Star is 44 degrees from the moon. Moon is 99% illuminated.
Stellar brightness G=15.8, apparent brightess of occulting body is G=15.0
Use an exposure time of 1.45 seconds with the standard RECON-QHY system.
Expected flux drop is 68% with SNR of 6.2 per integration
Apparent velocity is 11.8 km/sec on the sky relative to the star, or, 12.6 arcsec/hr.
The recommended exposure time corresponds to 17.2 km per image.
The 1-sigma error in the time of the event is 2.5 seconds.
The 1-sigma cross-track error in the shadow position is 31.2 km.
The sky-plane scale is 3371.1 km/arcsec.
Diameter estimates:
70.2 km assuming a 5% albedo, aximum of 5.9 sec for a central chord
28.6 km assuming a 30% albedo, maximum of 2.4 sec for a central chord
Cross-track diameter of 70.2 km used for deployment plan.
Star training set for 9799_Thronium, (2025/03/13 05:45UT) Object RA Dec mag sep mel Sirius 06:46:15.5 -16:45:08 -1.5 22.32 66 15Rho Pup 08:08:37.1 -24:22:42 2.8 12.57 52 PPM 219933 08:19:35.7 -12:43:08 6.1 1.11 44 PPM 219865 08:16:36.7 -11:22:17 8.2 0.58 44 PPM 219861 08:16:22.2 -12:00:33 8.9 0.07 44 9799_Thronium 08:16:19.5 -11:56:40 15.0 44 Positions are for equinox of date
Star training set for 9799_Thronium, (2025/03/13 05:45UT) Object RA Dec mag sep mel Sirius 06:45:07.9 -16:43:28 -1.5 22.32 66 15Rho Pup 08:07:32.5 -24:18:14 2.8 12.57 52 PPM 219933 08:18:24.4 -12:38:20 6.1 1.11 44 PPM 219865 08:15:24.8 -11:17:34 8.2 0.58 44 PPM 219861 08:15:10.7 -11:55:51 8.9 0.07 44 9799_Thronium 08:15:07.9 -11:51:58 15.0 44 Positions are for J2000