Occultation event with (4791) Iphidamas, event index number 1560
Regions able to see the event: SAmericaN
Geocentric closest approach at 2025/11/21 03:04:36 UTC
J2000 position of star is 01:10:35.9 +32:57:23
Equinox of date position of star is 01:12:02.4 +33:05:37
Star is 138 degrees from the moon. Moon is 1% illuminated.
Stellar brightness G=13.8, apparent brightess of occulting body is G=14.9
Use an exposure time of 0.20 seconds with the standard RECON-QHY system.
SNR of 8.7 per integration for unocculted signal
Expected flux drop is 74% with SNR of 6.5 for the occulted depth (per occulted point)
Apparent velocity is 16.2 km/sec on the sky relative to the star, or, 19.5 arcsec/hr.
Position angle of asteroid motion is 29.4 degrees
The recommended exposure time corresponds to 3.2 km per image.
The 1-sigma error in the time of the event is 1.6 seconds.
The 1-sigma cross-track error in the shadow position is 9.2 km.
The sky-plane scale is 2991.6 km/arcsec.
Diameter estimates:
59.2 km assuming a 5% albedo, aximum of 3.7 sec for a central chord
24.1 km assuming a 30% albedo, maximum of 1.5 sec for a central chord
Cross-track diameter of 49.5 km used for deployment plan.
Star training set for 4791_Iphidamas, (2025/11/21 03:05UT) Object RA Dec mag sep mel Aldebaran 04:37:24.6 +16:33:33 0.8 48.91 169 57Gam1And 02:05:30.0 +42:27:10 2.3 14.08 148 PPM 066072 01:14:43.3 +34:14:06 6.5 1.27 139 PPM 066053 01:13:56.9 +32:20:52 8.3 0.85 139 PPM 066023 01:11:50.6 +32:44:27 9.6 0.36 138 PPM 066016 01:11:23.5 +33:04:58 10.4 0.14 138 4791_Iphidamas 01:12:02.4 +33:05:37 14.9 139 Positions are for equinox of date
Star training set for 4791_Iphidamas, (2025/11/21 03:05UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 48.91 169 57Gam1And 02:03:54.1 +42:19:46 2.3 14.08 148 PPM 066072 01:13:16.2 +34:05:54 6.5 1.27 139 PPM 066053 01:12:30.4 +32:12:39 8.3 0.85 139 PPM 066023 01:10:24.2 +32:36:13 9.6 0.36 138 PPM 066016 01:09:57.1 +32:56:44 10.4 0.14 138 4791_Iphidamas 01:10:35.9 +32:57:23 14.9 138 Positions are for J2000