Occultation event with (4707) Khryses, event index number 1174
Regions able to see the event: SAfrica
Geocentric closest approach at 2025/07/28 02:13:43 UTC
J2000 position of star is 03:24:06.7 +25:34:00
Equinox of date position of star is 03:25:38.1 +25:39:21
Star is 110 degrees from the moon. Moon is 12% illuminated.
Stellar brightness G=15.9, apparent brightess of occulting body is G=16.0
Use an exposure time of 0.50 seconds with the standard RECON-QHY system.
SNR of 3.1 per integration for unocculted signal
Expected flux drop is 52% with SNR of 1.6 for the occulted depth (per occulted point)
Apparent velocity is 24.3 km/sec on the sky relative to the star, or, 24.8 arcsec/hr.
The recommended exposure time corresponds to 12.1 km per image.
The 1-sigma error in the time of the event is 1.9 seconds.
The 1-sigma cross-track error in the shadow position is 18.3 km.
The sky-plane scale is 3524.5 km/arcsec.
Diameter estimates:
43.8 km assuming a 5% albedo, aximum of 1.8 sec for a central chord
17.9 km assuming a 30% albedo, maximum of 0.7 sec for a central chord
Cross-track diameter of 43.8 km used for deployment plan.
Star training set for 4707_Khryses, (2025/07/28 02:14UT) Object RA Dec mag sep mel Aldebaran 04:37:23.5 +16:33:31 0.8 19.02 96 44Zet Per 03:55:44.8 +31:57:27 2.8 9.12 102 64 Ari 03:25:49.4 +24:48:46 5.5 0.84 111 60 Ari 03:21:56.9 +25:45:11 7.4 0.84 111 PPM 092462 03:25:03.9 +25:59:20 9.8 0.36 110 PPM 092464 03:25:15.9 +25:31:08 10.8 0.16 110 4707_Khryses 03:25:38.1 +25:39:21 16.0 110 Positions are for equinox of date
Star training set for 4707_Khryses, (2025/07/28 02:14UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 19.02 96 44Zet Per 03:54:07.9 +31:53:01 2.8 9.12 102 64 Ari 03:24:18.5 +24:43:25 5.5 0.84 111 60 Ari 03:20:25.6 +25:39:44 7.4 0.84 111 PPM 092462 03:23:32.4 +25:53:58 9.8 0.36 110 PPM 092464 03:23:44.6 +25:25:46 10.8 0.16 110 4707_Khryses 03:24:06.7 +25:34:00 16.0 110 Positions are for J2000