Occultation event with (16974) Iphthime, event index number 3781
Regions able to see the event: SAmericaN
Geocentric closest approach at 2026/06/05 01:17:21 UTC
J2000 position of star is 10:32:54.6 -06:09:10
Equinox of date position of star is 10:34:14.4 -06:17:22
Star is 140 degrees from the moon. Moon is 81% illuminated.
Stellar brightness G=16.1, apparent brightess of occulting body is G=15.8
Use an exposure time of 0.95 seconds with the standard RECON-QHY system.
SNR of 3.9 per integration for unocculted signal
Expected flux drop is 42% with SNR of 1.6 for the occulted depth (per occulted point)
Apparent velocity is 15.0 km/sec on the sky relative to the star, or, 13.7 arcsec/hr.
Position angle of asteroid motion is 81.1 degrees
The recommended exposure time corresponds to 14.3 km per image.
The 1-sigma error in the time of the event is 0.8 seconds.
The 1-sigma cross-track error in the shadow position is 58.9 km.
The sky-plane scale is 3937.6 km/arcsec.
Diameter estimates:
62.2 km assuming a 5% albedo, maximum of 4.1 sec for a central chord
25.4 km assuming a 30% albedo, maximum of 1.7 sec for a central chord
Cross-track diameter of 57.3 km used for deployment plan.
Star training set for 16974_Iphthime, (2026/06/05 01:17UT) Object RA Dec mag sep mel Regulus 10:09:46.6 +11:50:13 1.3 19.12 156 Alphard 09:28:53.2 -08:46:28 2.0 16.38 148 PPM 193503 10:32:18.2 -07:46:26 6.2 1.56 140 PPM 193522 10:33:48.4 -06:12:44 7.1 0.13 140 PPM 193529 10:34:18.2 -06:20:17 9.5 0.05 140 16974_Iphthime 10:34:14.4 -06:17:22 15.8 140 Positions are for equinox of date
Star training set for 16974_Iphthime, (2026/06/05 01:17UT) Object RA Dec mag sep mel Regulus 10:08:21.9 +11:58:02 1.3 19.12 156 Alphard 09:27:35.2 -08:39:30 2.0 16.38 148 PPM 193503 10:30:58.7 -07:38:15 6.2 1.56 140 PPM 193522 10:32:28.5 -06:04:32 7.1 0.13 140 PPM 193529 10:32:58.4 -06:12:05 9.5 0.05 140 16974_Iphthime 10:32:54.6 -06:09:10 15.8 140 Positions are for J2000