Occultation event with (17365) Thymbraeus, event index number 4015
Regions able to see the event: SAmericaN
Geocentric closest approach at 2026/08/15 09:15:56 UTC
J2000 position of star is 05:01:35.0 +23:55:45
Equinox of date position of star is 05:03:12.2 +23:57:58
Star is 101 degrees from the moon. Moon is 9% illuminated.
Stellar brightness G=15.7, apparent brightess of occulting body is G=16.2
Use an exposure time of 0.45 seconds with the standard RECON-QHY system.
SNR of 3.6 per integration for unocculted signal
Expected flux drop is 61% with SNR of 2.2 for the occulted depth (per occulted point)
Apparent velocity is 24.9 km/sec on the sky relative to the star, or, 23.1 arcsec/hr.
Position angle of asteroid motion is 89.4 degrees
The recommended exposure time corresponds to 11.2 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 42.7 km.
The sky-plane scale is 3877.1 km/arcsec.
Diameter estimates:
47.2 km assuming a 5% albedo, maximum of 1.9 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 44.9 km used for deployment plan.
Star training set for 17365_Thymbraeus, (2026/08/15 09:16UT) Object RA Dec mag sep mel Aldebaran 04:37:27.1 +16:33:38 0.8 9.55 107 Alnath 05:27:58.6 +28:37:38 1.6 7.25 95 PPM 094053 05:07:14.3 +23:05:43 6.5 1.27 100 PPM 093960 05:02:01.6 +24:12:01 8.4 0.36 101 PPM 093977 05:03:04.7 +23:49:01 9.5 0.15 101 17365_Thymbrae 05:03:12.2 +23:57:58 16.2 100 Positions are for equinox of date
Star training set for 17365_Thymbraeus, (2026/08/15 09:16UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 9.55 107 Alnath 05:26:17.6 +28:36:22 1.6 7.25 95 PPM 094053 05:05:37.7 +23:03:40 6.5 1.27 100 PPM 093960 05:00:24.3 +24:09:45 8.4 0.36 101 PPM 093977 05:01:27.7 +23:46:48 9.5 0.15 101 17365_Thymbrae 05:01:35.0 +23:55:45 16.2 101 Positions are for J2000