Occultation event with (17365) Thymbraeus, event index number 1132
Regions able to see the event: Australia
Geocentric closest approach at 2025/07/12 21:12:58 UTC
J2000 position of star is 02:24:07.0 +22:15:13
Equinox of date position of star is 02:25:33.8 +22:22:06
Star is 86 degrees from the moon. Moon is 95% illuminated.
Stellar brightness G=15.4, apparent brightess of occulting body is G=16.0
Use an exposure time of 0.45 seconds with the standard RECON-QHY system.
SNR of 4.5 per integration for unocculted signal
Expected flux drop is 64% with SNR of 2.9 for the occulted depth (per occulted point)
Apparent velocity is 23.7 km/sec on the sky relative to the star, or, 22.9 arcsec/hr.
The recommended exposure time corresponds to 10.7 km per image.
The 1-sigma error in the time of the event is 1.9 seconds.
The 1-sigma cross-track error in the shadow position is 16.0 km.
The sky-plane scale is 3723.1 km/arcsec.
Diameter estimates:
47.2 km assuming a 5% albedo, aximum of 2.0 sec for a central chord
19.3 km assuming a 30% albedo, maximum of 0.8 sec for a central chord
Cross-track diameter of 47.2 km used for deployment plan.
Star training set for 17365_Thymbraeus, (2025/07/12 21:13UT) Object RA Dec mag sep mel Aldebaran 04:37:23.3 +16:33:31 0.8 31.55 114 Hamal 02:08:37.1 +23:34:55 2.0 4.08 83 22The Ari 02:19:33.1 +20:01:05 5.6 2.74 84 PPM 091645 02:26:06.9 +22:32:54 8.5 0.22 86 17365_Thymbrae 02:25:33.8 +22:22:06 16.0 87 Positions are for equinox of date
Star training set for 17365_Thymbraeus, (2025/07/12 21:13UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 31.55 114 Hamal 02:07:10.8 +23:27:41 2.0 4.08 83 22The Ari 02:18:07.5 +19:54:04 5.6 2.74 84 PPM 091645 02:24:40.0 +22:26:02 8.5 0.22 86 17365_Thymbrae 02:24:07.0 +22:15:13 16.0 86 Positions are for J2000