Occultation event with (4707) Khryses, event index number 1681
Regions able to see the event: Australia
Geocentric closest approach at 2025/12/14 12:14:05 UTC
J2000 position of star is 03:06:15.9 +26:06:59
Equinox of date position of star is 03:07:48.1 +26:12:55
Star is 151 degrees from the moon. Moon is 26% illuminated.
Stellar brightness G=16.4, apparent brightess of occulting body is G=15.3
Use an exposure time of 0.95 seconds with the standard RECON-QHY system.
SNR of 3.1 per integration for unocculted signal
Expected flux drop is 26% with SNR of 0.8 for the occulted depth (per occulted point)
Apparent velocity is 11.7 km/sec on the sky relative to the star, or, 15.2 arcsec/hr.
Position angle of asteroid motion is 61.1 degrees
The recommended exposure time corresponds to 11.1 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 25.1 km.
The sky-plane scale is 2769.1 km/arcsec.
Diameter estimates:
43.8 km assuming a 5% albedo, aximum of 3.7 sec for a central chord
17.9 km assuming a 30% albedo, maximum of 1.5 sec for a central chord
Cross-track diameter of 37.8 km used for deployment plan.
Star training set for 4707_Khryses, (2025/12/14 12:14UT) Object RA Dec mag sep mel Aldebaran 04:37:24.8 +16:33:34 0.8 22.94 132 44Zet Per 03:55:46.2 +31:57:31 2.8 11.94 139 52 Ari 03:06:58.4 +25:21:16 6.1 0.88 151 PPM 092198 03:07:02.9 +25:58:05 8.8 0.30 151 PPM 092207 03:07:44.9 +26:08:20 10.4 0.08 151 4707_Khryses 03:07:48.1 +26:12:55 15.3 150 Positions are for equinox of date
Star training set for 4707_Khryses, (2025/12/14 12:14UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 22.94 132 44Zet Per 03:54:07.9 +31:53:01 2.8 11.94 139 52 Ari 03:05:26.7 +25:15:19 6.1 0.88 151 PPM 092198 03:05:30.8 +25:52:07 8.8 0.30 151 PPM 092207 03:06:12.7 +26:02:23 10.4 0.08 151 4707_Khryses 03:06:15.9 +26:06:59 15.3 151 Positions are for J2000