Occultation event with (7641) Cteatus, event index number 904
Regions able to see the event: Australia
Geocentric closest approach at 2025/04/15 09:18:28 UTC
J2000 position of star is 07:48:58.8 -15:03:48
Equinox of date position of star is 07:50:08.4 -15:07:42
Star is 102 degrees from the moon. Moon is 95% illuminated.
Stellar brightness G=16.4, apparent brightess of occulting body is G=14.9
Use an exposure time of 1.20 seconds with the standard RECON-QHY system.
SNR of 3.2 per integration for unocculted signal
Expected flux drop is 19% with SNR of 0.6 for the occulted depth (per occulted point)
Apparent velocity is 15.6 km/sec on the sky relative to the star, or, 16.3 arcsec/hr.
The recommended exposure time corresponds to 18.8 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 30.5 km.
The sky-plane scale is 3444.8 km/arcsec.
Diameter estimates:
76.2 km assuming a 5% albedo, aximum of 4.9 sec for a central chord
31.1 km assuming a 30% albedo, maximum of 2.0 sec for a central chord
Cross-track diameter of 76.2 km used for deployment plan.
Star training set for 7641_Cteatus, (2025/04/15 09:18UT) Object RA Dec mag sep mel Sirius 06:46:15.7 -16:45:09 -1.5 15.44 115 15Rho Pup 08:08:37.3 -24:22:43 2.8 10.22 94 4 Pup 07:47:06.7 -14:37:37 5.0 0.89 103 PPM 219239 07:50:22.5 -15:21:41 8.5 0.24 102 7641_Cteatus 07:50:08.4 -15:07:42 14.9 102 Positions are for equinox of date
Star training set for 7641_Cteatus, (2025/04/15 09:18UT) Object RA Dec mag sep mel Sirius 06:45:07.9 -16:43:28 -1.5 15.44 115 15Rho Pup 08:07:32.5 -24:18:14 2.8 10.22 94 4 Pup 07:45:56.8 -14:33:50 5.0 0.89 103 PPM 219239 07:49:12.9 -15:17:48 8.5 0.24 102 7641_Cteatus 07:48:58.8 -15:03:48 14.9 102 Positions are for J2000