Occultation event with (7641) Cteatus, event index number 3581
Regions able to see the event: Europe
Geocentric closest approach at 2026/04/05 19:58:03 UTC
J2000 position of star is 10:12:39.8 -31:19:26
Equinox of date position of star is 10:13:50.9 -31:27:16
Star is 71 degrees from the moon. Moon is 87% illuminated.
Stellar brightness G=11.4, apparent brightess of occulting body is G=14.6
Use an exposure time of 0.12 seconds with the standard RECON-QHY system.
SNR of 30.5 per integration for unocculted signal
Expected flux drop is 95% with SNR of 29.0 for the occulted depth (per occulted point)
Apparent velocity is 17.0 km/sec on the sky relative to the star, or, 19.6 arcsec/hr.
Position angle of asteroid motion is 154.3 degrees
The recommended exposure time corresponds to 2.0 km per image.
The 1-sigma error in the time of the event is 2.7 seconds.
The 1-sigma cross-track error in the shadow position is 5.8 km.
The sky-plane scale is 3126.1 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, (2026/04/05 19:58UT) Object RA Dec mag sep mel Bet Cru 12:49:16.5 -59:49:54 1.3 38.28 46 Lam Vel 09:08:57.8 -43:32:23 2.2 17.59 79 PPM 287271 10:06:56.0 -31:01:13 6.5 1.54 72 PPM 287447 10:14:39.8 -31:40:03 8.4 0.27 70 PPM 287430 10:13:59.6 -31:24:57 9.8 0.05 71 7641_Cteatus 10:13:50.9 -31:27:16 14.6 70 Positions are for equinox of date
Star training set for 7641_Cteatus, (2026/04/05 19:58UT) Object RA Dec mag sep mel Bet Cru 12:47:43.1 -59:41:20 1.3 38.28 46 Lam Vel 09:07:59.7 -43:25:57 2.2 17.59 79 PPM 287271 10:05:45.2 -30:53:30 6.5 1.54 72 PPM 287447 10:13:28.7 -31:32:12 8.4 0.27 70 PPM 287430 10:12:48.4 -31:17:06 9.8 0.05 71 7641_Cteatus 10:12:39.8 -31:19:26 14.6 71 Positions are for J2000