Occultation event with (34746) Thoon, event index number 4180
Regions able to see the event: SAmericaN
Geocentric closest approach at 2026/09/05 04:52:55 UTC
J2000 position of star is 04:43:21.8 +05:10:53
Equinox of date position of star is 04:44:46.9 +05:13:47
Star is 26 degrees from the moon. Moon is 40% illuminated.
Stellar brightness G=12.1, apparent brightess of occulting body is G=15.5
Use an exposure time of 0.12 seconds with the standard RECON-QHY system.
SNR of 20.2 per integration for unocculted signal
Expected flux drop is 96% with SNR of 19.4 for the occulted depth (per occulted point)
Apparent velocity is 10.2 km/sec on the sky relative to the star, or, 9.9 arcsec/hr.
Position angle of asteroid motion is 99.5 degrees
The recommended exposure time corresponds to 1.2 km per image.
The 1-sigma error in the time of the event is 1.0 seconds.
The 1-sigma cross-track error in the shadow position is 22.4 km.
The sky-plane scale is 3710.8 km/arcsec.
Diameter estimates:
64.0 km assuming a 5% albedo, maximum of 6.3 sec for a central chord
26.1 km assuming a 30% albedo, maximum of 2.6 sec for a central chord
Cross-track diameter of 61.7 km used for deployment plan.
Star training set for 34746_Thoon, (2026/09/05 04:53UT) Object RA Dec mag sep mel Aldebaran 04:37:27.3 +16:33:39 0.8 11.47 18 Bellatrix 05:26:33.8 +06:22:18 1.6 10.45 22 PPM 147967 04:48:43.4 +05:50:03 6.4 1.15 25 PPM 147869 04:44:52.3 +05:00:41 8.4 0.22 26 PPM 147865 04:44:48.4 +05:18:18 9.9 0.08 26 34746_Thoon 04:44:46.9 +05:13:47 15.5 26 Positions are for equinox of date
Star training set for 34746_Thoon, (2026/09/05 04:53UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 11.47 18 Bellatrix 05:25:07.8 +06:20:58 1.6 10.45 22 PPM 147967 04:47:18.0 +05:47:17 6.4 1.15 25 PPM 147869 04:43:27.3 +04:57:47 8.4 0.22 26 PPM 147865 04:43:23.2 +05:15:24 9.9 0.08 26 34746_Thoon 04:43:21.8 +05:10:53 15.5 26 Positions are for J2000