Occultation event with (17365) Thymbraeus, event index number 1212
Regions able to see the event: SAmericaN,SAmericaS
Geocentric closest approach at 2025/08/06 07:12:15 UTC
J2000 position of star is 02:36:14.4 +23:25:05
Equinox of date position of star is 02:37:42.5 +23:31:43
Star is 127 degrees from the moon. Moon is 90% illuminated.
Stellar brightness G=12.9, apparent brightess of occulting body is G=15.9
Use an exposure time of 0.12 seconds with the standard RECON-QHY system.
SNR of 11.6 per integration for unocculted signal
Expected flux drop is 94% with SNR of 10.9 for the occulted depth (per occulted point)
Apparent velocity is 13.3 km/sec on the sky relative to the star, or, 13.8 arcsec/hr.
Position angle of asteroid motion is 65.8 degrees
The recommended exposure time corresponds to 1.6 km per image.
The 1-sigma error in the time of the event is 1.6 seconds.
The 1-sigma cross-track error in the shadow position is 33.2 km.
The sky-plane scale is 3464.4 km/arcsec.
Diameter estimates:
47.2 km assuming a 5% albedo, aximum of 3.5 sec for a central chord
19.3 km assuming a 30% albedo, maximum of 1.4 sec for a central chord
Cross-track diameter of 44.9 km used for deployment plan.
Star training set for 17365_Thymbraeus, (2025/08/06 07:12UT) Object RA Dec mag sep mel Aldebaran 04:37:23.5 +16:33:31 0.8 28.90 151 Hamal 02:08:37.3 +23:34:56 2.0 6.67 121 32Nu Ari 02:40:16.6 +22:04:14 5.4 1.57 127 PPM 091828 02:38:10.0 +23:09:48 8.4 0.38 127 PPM 091833 02:38:33.1 +23:33:57 10.6 0.20 127 17365_Thymbrae 02:37:42.5 +23:31:43 15.9 127 Positions are for equinox of date
Star training set for 17365_Thymbraeus, (2025/08/06 07:12UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 28.90 151 Hamal 02:07:10.8 +23:27:41 2.0 6.67 121 32Nu Ari 02:38:49.0 +21:57:41 5.4 1.57 127 PPM 091828 02:36:42.0 +23:03:12 8.4 0.38 127 PPM 091833 02:37:04.9 +23:27:21 10.6 0.20 127 17365_Thymbrae 02:36:14.4 +23:25:05 15.9 127 Positions are for J2000