Occultation event with (4791) Iphidamas, event index number 5184
Regions able to see the event: NMexico,SMexico
Geocentric closest approach at 2026/12/12 08:35:51 UTC
J2000 position of star is 04:12:53.6 +28:37:48
Equinox of date position of star is 04:14:34.1 +28:41:49
Star is 130 degrees from the moon. Moon is 10% illuminated.
Stellar brightness G=16.3, apparent brightess of occulting body is G=14.6
Use an exposure time of 1.00 seconds with the standard RECON-QHY system.
SNR of 3.0 per integration for unocculted signal
Expected flux drop is 17% with SNR of 0.5 for the occulted depth (per occulted point)
Apparent velocity is 18.2 km/sec on the sky relative to the star, or, 22.9 arcsec/hr.
Position angle of asteroid motion is 57.9 degrees
The recommended exposure time corresponds to 18.2 km per image.
The 1-sigma error in the time of the event is 0.5 seconds.
The 1-sigma cross-track error in the shadow position is 28.5 km.
The sky-plane scale is 2868.0 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, (2026/12/12 08:36UT) Object RA Dec mag sep mel Aldebaran 04:37:28.2 +16:33:41 0.8 13.23 133 44Zet Per 03:55:50.0 +31:57:41 2.8 5.19 126 44 Tau 04:12:28.6 +26:32:56 5.4 2.20 129 PPM 093364 04:16:52.2 +29:58:00 8.2 1.37 131 PPM 093328 04:14:01.7 +28:30:09 9.8 0.23 130 4791_Iphidamas 04:14:34.1 +28:41:49 14.6 131 Positions are for equinox of date
Star training set for 4791_Iphidamas, (2026/12/12 08:36UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 13.23 133 44Zet Per 03:54:07.9 +31:53:01 2.8 5.19 126 44 Tau 04:10:49.8 +26:28:50 5.4 2.20 129 PPM 093364 04:15:10.7 +29:54:03 8.2 1.37 131 PPM 093328 04:12:21.4 +28:26:06 9.8 0.23 130 4791_Iphidamas 04:12:53.6 +28:37:48 14.6 130 Positions are for J2000