Occultation event with (17365) Thymbraeus, event index number 1525
Regions able to see the event: Europe
Geocentric closest approach at 2025/11/17 02:56:25 UTC
J2000 position of star is 02:13:19.7 +21:16:39
Equinox of date position of star is 02:14:46.7 +21:23:51
Star is 162 degrees from the moon. Moon is 9% illuminated.
Stellar brightness G=14.1, apparent brightess of occulting body is G=15.1
Use an exposure time of 0.30 seconds with the standard RECON-QHY system.
SNR of 9.0 per integration for unocculted signal
Expected flux drop is 71% with SNR of 6.4 for the occulted depth (per occulted point)
Apparent velocity is 15.5 km/sec on the sky relative to the star, or, 19.4 arcsec/hr.
Position angle of asteroid motion is 57.5 degrees
The recommended exposure time corresponds to 4.6 km per image.
The 1-sigma error in the time of the event is 1.7 seconds.
The 1-sigma cross-track error in the shadow position is 29.3 km.
The sky-plane scale is 2868.0 km/arcsec.
Diameter estimates:
47.2 km assuming a 5% albedo, aximum of 3.0 sec for a central chord
19.3 km assuming a 30% albedo, maximum of 1.2 sec for a central chord
Cross-track diameter of 44.9 km used for deployment plan.
Star training set for 17365_Thymbraeus, (2025/11/17 02:56UT) Object RA Dec mag sep mel Aldebaran 04:37:24.5 +16:33:33 0.8 33.99 130 Hamal 02:08:38.3 +23:35:01 2.0 2.61 162 17Eta Ari 02:14:15.4 +21:19:53 5.8 0.14 162 PPM 091428 02:12:50.6 +21:29:53 8.1 0.46 162 17Eta Ari 02:14:15.4 +21:19:53 5.8 0.14 162 17365_Thymbrae 02:14:46.7 +21:23:51 15.1 162 Positions are for equinox of date
Star training set for 17365_Thymbraeus, (2025/11/17 02:56UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 33.99 130 Hamal 02:07:10.8 +23:27:41 2.0 2.61 162 17Eta Ari 02:12:48.4 +21:12:40 5.8 0.14 162 PPM 091428 02:11:23.6 +21:22:38 8.1 0.46 162 17Eta Ari 02:12:48.4 +21:12:40 5.8 0.14 162 17365_Thymbrae 02:13:19.7 +21:16:39 15.1 162 Positions are for J2000