Occultation event with (16974) Iphthime, event index number 1367
Regions able to see the event: Senegal
Geocentric closest approach at 2025/10/13 05:54:54 UTC
J2000 position of star is 10:32:43.2 -05:04:15
Equinox of date position of star is 10:34:01.4 -05:12:15
Star is 60 degrees from the moon. Moon is 56% illuminated.
Stellar brightness G=14.7, apparent brightess of occulting body is G=15.9
Use an exposure time of 0.40 seconds with the standard RECON-QHY system.
SNR of 7.4 per integration for unocculted signal
Expected flux drop is 75% with SNR of 5.5 for the occulted depth (per occulted point)
Apparent velocity is 35.7 km/sec on the sky relative to the star, or, 28.8 arcsec/hr.
Position angle of asteroid motion is 118.4 degrees
The recommended exposure time corresponds to 14.3 km per image.
The 1-sigma error in the time of the event is 1.2 seconds.
The 1-sigma cross-track error in the shadow position is 38.7 km.
The sky-plane scale is 4460.5 km/arcsec.
Diameter estimates:
62.2 km assuming a 5% albedo, aximum of 1.7 sec for a central chord
25.4 km assuming a 30% albedo, maximum of 0.7 sec for a central chord
Cross-track diameter of 57.3 km used for deployment plan.
Star training set for 16974_Iphthime, (2025/10/13 05:55UT) Object RA Dec mag sep mel Regulus 10:09:44.5 +11:50:25 1.3 18.08 46 Alphard 09:28:51.3 -08:46:18 2.0 16.56 51 PPM 193464 10:30:02.4 -03:52:30 6.5 1.66 59 PPM 193533 10:34:32.9 -05:29:50 7.5 0.32 61 PPM 193525 10:33:54.2 -05:07:06 9.6 0.09 60 16974_Iphthime 10:34:01.4 -05:12:15 15.9 61 Positions are for equinox of date
Star training set for 16974_Iphthime, (2025/10/13 05:55UT) Object RA Dec mag sep mel Regulus 10:08:21.9 +11:58:02 1.3 18.08 46 Alphard 09:27:35.2 -08:39:30 2.0 16.56 51 PPM 193464 10:28:44.0 -03:44:33 6.5 1.66 59 PPM 193533 10:33:14.8 -05:21:49 7.5 0.32 61 PPM 193525 10:32:36.1 -04:59:06 9.6 0.09 60 16974_Iphthime 10:32:43.2 -05:04:15 15.9 60 Positions are for J2000