Occultation event with (4791) Iphidamas, event index number 5040
Regions able to see the event: SAmericaN
Geocentric closest approach at 2026/12/05 04:08:40 UTC
J2000 position of star is 04:17:16.8 +29:12:02
Equinox of date position of star is 04:18:57.7 +29:15:54
Star is 142 degrees from the moon. Moon is 14% illuminated.
Stellar brightness G=13.6, apparent brightess of occulting body is G=14.5
Use an exposure time of 0.20 seconds with the standard RECON-QHY system.
SNR of 9.9 per integration for unocculted signal
Expected flux drop is 70% with SNR of 6.9 for the occulted depth (per occulted point)
Apparent velocity is 18.7 km/sec on the sky relative to the star, or, 23.6 arcsec/hr.
Position angle of asteroid motion is 60.5 degrees
The recommended exposure time corresponds to 3.7 km per image.
The 1-sigma error in the time of the event is 0.4 seconds.
The 1-sigma cross-track error in the shadow position is 29.6 km.
The sky-plane scale is 2854.5 km/arcsec.
Diameter estimates:
59.2 km assuming a 5% albedo, maximum of 3.2 sec for a central chord
24.1 km assuming a 30% albedo, maximum of 1.3 sec for a central chord
Cross-track diameter of 49.5 km used for deployment plan.
Star training set for 4791_Iphidamas, (2026/12/05 04:09UT) Object RA Dec mag sep mel Aldebaran 04:37:28.1 +16:33:40 0.8 13.40 139 44Zet Per 03:55:49.9 +31:57:41 2.8 5.66 146 PPM 069410 04:27:49.5 +31:29:51 5.3 2.94 140 PPM 093434 04:22:18.7 +28:57:15 8.0 0.79 142 PPM 093379 04:18:00.1 +29:19:18 10.6 0.22 142 4791_Iphidamas 04:18:57.7 +29:15:54 14.5 142 Positions are for equinox of date
Star training set for 4791_Iphidamas, (2026/12/05 04:09UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 13.40 139 44Zet Per 03:54:07.9 +31:53:01 2.8 5.66 146 PPM 069410 04:26:06.4 +31:26:18 5.3 2.94 140 PPM 093434 04:20:37.8 +28:53:31 8.0 0.79 142 PPM 093379 04:16:19.1 +29:15:24 10.6 0.22 142 4791_Iphidamas 04:17:16.8 +29:12:02 14.5 142 Positions are for J2000