Occultation event with (34746) Thoon, event index number 4032
Regions able to see the event: SAmericaN
Geocentric closest approach at 2026/08/17 07:43:28 UTC
J2000 position of star is 04:36:32.4 +05:17:22
Equinox of date position of star is 04:37:57.3 +05:20:31
Star is 130 degrees from the moon. Moon is 24% illuminated.
Stellar brightness G=15.6, apparent brightess of occulting body is G=15.6
Use an exposure time of 0.80 seconds with the standard RECON-QHY system.
SNR of 5.3 per integration for unocculted signal
Expected flux drop is 49% with SNR of 2.6 for the occulted depth (per occulted point)
Apparent velocity is 18.5 km/sec on the sky relative to the star, or, 17.0 arcsec/hr.
Position angle of asteroid motion is 90.0 degrees
The recommended exposure time corresponds to 14.8 km per image.
The 1-sigma error in the time of the event is 0.7 seconds.
The 1-sigma cross-track error in the shadow position is 20.5 km.
The sky-plane scale is 3911.3 km/arcsec.
Diameter estimates:
64.0 km assuming a 5% albedo, maximum of 3.5 sec for a central chord
26.1 km assuming a 30% albedo, maximum of 1.4 sec for a central chord
Cross-track diameter of 61.7 km used for deployment plan.
Star training set for 34746_Thoon, (2026/08/17 07:43UT) Object RA Dec mag sep mel Aldebaran 04:37:27.1 +16:33:38 0.8 11.22 132 Bellatrix 05:26:33.6 +06:22:18 1.6 12.13 119 PPM 147685 04:35:33.4 +05:37:21 5.8 0.66 131 PPM 147753 04:39:02.1 +05:02:04 7.4 0.41 130 PPM 147729 04:38:13.6 +05:25:40 9.4 0.11 130 34746_Thoon 04:37:57.3 +05:20:31 15.6 130 Positions are for equinox of date
Star training set for 34746_Thoon, (2026/08/17 07:43UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 11.22 132 Bellatrix 05:25:07.8 +06:20:58 1.6 12.13 119 PPM 147685 04:34:08.2 +05:34:08 5.8 0.66 131 PPM 147753 04:37:37.3 +04:58:58 7.4 0.41 130 PPM 147729 04:36:48.6 +05:22:32 9.4 0.11 130 34746_Thoon 04:36:32.4 +05:17:22 15.6 130 Positions are for J2000