Occultation event with (4791) Iphidamas, event index number 4073
Regions able to see the event: SAmericaN
Geocentric closest approach at 2026/08/22 05:29:27 UTC
J2000 position of star is 04:33:09.6 +32:03:49
Equinox of date position of star is 04:34:52.3 +32:07:04
Star is 168 degrees from the moon. Moon is 70% illuminated.
Stellar brightness G=15.2, apparent brightess of occulting body is G=15.5
Use an exposure time of 0.65 seconds with the standard RECON-QHY system.
SNR of 6.9 per integration for unocculted signal
Expected flux drop is 58% with SNR of 4.0 for the occulted depth (per occulted point)
Apparent velocity is 18.2 km/sec on the sky relative to the star, or, 18.0 arcsec/hr.
Position angle of asteroid motion is 84.6 degrees
The recommended exposure time corresponds to 11.8 km per image.
The 1-sigma error in the time of the event is 0.3 seconds.
The 1-sigma cross-track error in the shadow position is 28.4 km.
The sky-plane scale is 3649.6 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, (2026/08/22 05:29UT) Object RA Dec mag sep mel Aldebaran 04:37:27.1 +16:33:38 0.8 15.57 164 3Iot Aur 04:58:44.0 +33:12:20 2.7 5.14 172 PPM 069458 04:32:21.3 +32:30:49 6.2 0.66 167 PPM 069491 04:34:35.4 +31:50:24 8.5 0.28 168 4791_Iphidamas 04:34:52.3 +32:07:04 15.5 168 Positions are for equinox of date
Star training set for 4791_Iphidamas, (2026/08/22 05:29UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 15.57 164 3Iot Aur 04:56:59.6 +33:09:57 2.7 5.14 172 PPM 069458 04:30:38.4 +32:27:28 6.2 0.66 167 PPM 069491 04:32:52.9 +31:47:08 8.5 0.28 168 4791_Iphidamas 04:33:09.6 +32:03:49 15.5 168 Positions are for J2000