Occultation event with (7641) Cteatus, event index number 3732
Regions able to see the event: SAfrica
Geocentric closest approach at 2026/05/09 17:32:15 UTC
J2000 position of star is 10:11:43.3 -27:13:54
Equinox of date position of star is 10:12:56.2 -27:21:45
Star is 134 degrees from the moon. Moon is 52% illuminated.
Stellar brightness G=15.5, apparent brightess of occulting body is G=14.8
Use an exposure time of 1.05 seconds with the standard RECON-QHY system.
SNR of 6.3 per integration for unocculted signal
Expected flux drop is 34% with SNR of 2.1 for the occulted depth (per occulted point)
Apparent velocity is 16.9 km/sec on the sky relative to the star, or, 18.3 arcsec/hr.
Position angle of asteroid motion is 22.5 degrees
The recommended exposure time corresponds to 17.8 km per image.
The 1-sigma error in the time of the event is 2.1 seconds.
The 1-sigma cross-track error in the shadow position is 29.7 km.
The sky-plane scale is 3334.7 km/arcsec.
Diameter estimates:
76.6 km assuming a 5% albedo, maximum of 4.5 sec for a central chord
31.3 km assuming a 30% albedo, maximum of 1.8 sec for a central chord
Cross-track diameter of 71.8 km used for deployment plan.
Star training set for 7641_Cteatus, (2026/05/09 17:32UT) Object RA Dec mag sep mel Bet Cru 12:49:16.8 -59:49:56 1.3 41.94 93 Lam Vel 09:08:58.0 -43:32:24 2.2 20.69 119 PPM 257358 10:14:32.3 -27:09:36 6.4 0.41 134 PPM 257337 10:13:23.6 -27:23:29 8.4 0.11 134 PPM 257316 10:12:30.3 -27:22:22 9.5 0.10 134 7641_Cteatus 10:12:56.2 -27:21:45 14.8 134 Positions are for equinox of date
Star training set for 7641_Cteatus, (2026/05/09 17:32UT) Object RA Dec mag sep mel Bet Cru 12:47:43.1 -59:41:20 1.3 41.94 93 Lam Vel 09:07:59.7 -43:25:57 2.2 20.69 119 PPM 257358 10:13:19.3 -27:01:43 6.4 0.41 134 PPM 257337 10:12:10.7 -27:15:38 8.4 0.11 134 PPM 257316 10:11:17.6 -27:14:31 9.5 0.10 134 7641_Cteatus 10:11:43.3 -27:13:54 14.8 134 Positions are for J2000