Occultation event with (4834) Thoas, event index number 3772
Regions able to see the event: Australia
Geocentric closest approach at 2026/05/31 10:37:54 UTC
J2000 position of star is 12:19:48.9 +29:41:15
Equinox of date position of star is 12:21:08.3 +29:32:27
Star is 83 degrees from the moon. Moon is 100% illuminated.
Stellar brightness G=12.8, apparent brightess of occulting body is G=14.8
Use an exposure time of 0.12 seconds with the standard RECON-QHY system.
SNR of 12.0 per integration for unocculted signal
Expected flux drop is 86% with SNR of 10.3 for the occulted depth (per occulted point)
Apparent velocity is 15.8 km/sec on the sky relative to the star, or, 15.3 arcsec/hr.
Position angle of asteroid motion is 3.6 degrees
The recommended exposure time corresponds to 1.9 km per image.
The 1-sigma error in the time of the event is 2.0 seconds.
The 1-sigma cross-track error in the shadow position is 21.0 km.
The sky-plane scale is 3701.9 km/arcsec.
Diameter estimates:
89.1 km assuming a 5% albedo, maximum of 5.7 sec for a central chord
36.4 km assuming a 30% albedo, maximum of 2.3 sec for a central chord
Cross-track diameter of 72.3 km used for deployment plan.
Star training set for 4834_Thoas, (2026/05/31 10:38UT) Object RA Dec mag sep mel Arcturus 14:16:52.1 +19:02:47 0.0 28.28 57 Denebola 11:50:24.3 +14:25:28 2.1 16.70 81 PPM 076403 12:19:51.3 +30:06:06 6.2 0.63 84 PPM 076413 12:20:50.5 +30:01:18 9.6 0.48 83 PPM 101821 12:21:59.9 +29:23:14 10.8 0.24 83 4834_Thoas 12:21:08.3 +29:32:27 14.8 83 Positions are for equinox of date
Star training set for 4834_Thoas, (2026/05/31 10:38UT) Object RA Dec mag sep mel Arcturus 14:15:37.7 +19:10:06 0.0 28.28 57 Denebola 11:49:02.7 +14:34:16 2.1 16.70 81 PPM 076403 12:18:31.8 +30:14:54 6.2 0.63 84 PPM 076413 12:19:31.1 +30:10:05 9.6 0.48 83 PPM 101821 12:20:40.6 +29:32:01 10.8 0.24 83 4834_Thoas 12:19:48.9 +29:41:15 14.8 83 Positions are for J2000