Occultation event with (7641) Cteatus, event index number 974
Regions able to see the event: Australia
Geocentric closest approach at 2025/05/15 09:22:17 UTC
J2000 position of star is 08:03:42.6 -13:17:03
Equinox of date position of star is 08:04:53.7 -13:21:25
Star is 125 degrees from the moon. Moon is 93% illuminated.
Stellar brightness G=16.0, apparent brightess of occulting body is G=15.0
Use an exposure time of 0.75 seconds with the standard RECON-QHY system.
SNR of 3.6 per integration for unocculted signal
Expected flux drop is 29% with SNR of 1.1 for the occulted depth (per occulted point)
Apparent velocity is 24.8 km/sec on the sky relative to the star, or, 24.0 arcsec/hr.
The recommended exposure time corresponds to 18.6 km per image.
The 1-sigma error in the time of the event is 1.7 seconds.
The 1-sigma cross-track error in the shadow position is 24.3 km.
The sky-plane scale is 3719.3 km/arcsec.
Diameter estimates:
76.2 km assuming a 5% albedo, aximum of 3.1 sec for a central chord
31.1 km assuming a 30% albedo, maximum of 1.3 sec for a central chord
Cross-track diameter of 76.2 km used for deployment plan.
Star training set for 7641_Cteatus, (2025/05/15 09:22UT) Object RA Dec mag sep mel Sirius 06:46:15.9 -16:45:09 -1.5 19.27 132 15Rho Pup 08:08:37.5 -24:22:44 2.8 11.06 116 18 Pup 08:11:50.4 -13:52:31 5.7 1.77 124 PPM 219584 08:04:35.0 -13:16:35 8.4 0.11 125 7641_Cteatus 08:04:53.7 -13:21:25 15.0 125 Positions are for equinox of date
Star training set for 7641_Cteatus, (2025/05/15 09:22UT) Object RA Dec mag sep mel Sirius 06:45:07.9 -16:43:28 -1.5 19.27 132 15Rho Pup 08:07:32.5 -24:18:14 2.8 11.06 116 18 Pup 08:10:39.4 -13:47:56 5.7 1.77 124 PPM 219584 08:03:23.9 -13:12:13 8.4 0.11 125 7641_Cteatus 08:03:42.6 -13:17:03 15.0 125 Positions are for J2000