Occultation event with (7641) Cteatus, event index number 3497
Regions able to see the event: SAmericaS
Geocentric closest approach at 2026/03/25 08:45:22 UTC
J2000 position of star is 10:16:32.2 -32:35:58
Equinox of date position of star is 10:17:43.1 -32:43:51
Star is 87 degrees from the moon. Moon is 45% illuminated.
Stellar brightness G=15.4, apparent brightess of occulting body is G=14.5
Use an exposure time of 1.00 seconds with the standard RECON-QHY system.
SNR of 6.9 per integration for unocculted signal
Expected flux drop is 31% with SNR of 2.2 for the occulted depth (per occulted point)
Apparent velocity is 17.2 km/sec on the sky relative to the star, or, 20.1 arcsec/hr.
Position angle of asteroid motion is 140.4 degrees
The recommended exposure time corresponds to 17.2 km per image.
The 1-sigma error in the time of the event is 2.5 seconds.
The 1-sigma cross-track error in the shadow position is 16.9 km.
The sky-plane scale is 3092.6 km/arcsec.
Diameter estimates:
76.6 km assuming a 5% albedo, maximum of 4.4 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, (2026/03/25 08:45UT) Object RA Dec mag sep mel Bet Cru 12:49:16.4 -59:49:54 1.3 36.77 121 Lam Vel 09:08:57.8 -43:32:22 2.2 17.25 84 PPM 287445 10:14:34.5 -33:09:43 6.5 0.79 87 PPM 287541 10:19:49.2 -32:40:13 7.6 0.45 87 PPM 287515 10:18:24.3 -32:49:16 9.2 0.17 87 7641_Cteatus 10:17:43.1 -32:43:51 14.5 87 Positions are for equinox of date
Star training set for 7641_Cteatus, (2026/03/25 08:45UT) Object RA Dec mag sep mel Bet Cru 12:47:43.1 -59:41:20 1.3 36.77 121 Lam Vel 09:07:59.7 -43:25:57 2.2 17.25 84 PPM 287445 10:13:24.0 -33:01:53 6.5 0.79 87 PPM 287541 10:18:38.1 -32:32:18 7.6 0.45 87 PPM 287515 10:17:13.4 -32:41:22 9.2 0.17 87 7641_Cteatus 10:16:32.2 -32:35:58 14.5 87 Positions are for J2000