Occultation event with (17172) 99NZ41, event index number 4410
Regions able to see the event: SAfrica
Geocentric closest approach at 2026/10/16 02:03:15 UTC
J2000 position of star is 06:33:41.6 -00:39:24
Equinox of date position of star is 06:35:03.5 -00:40:44
Star is 148 degrees from the moon. Moon is 27% illuminated.
Stellar brightness G=15.7, apparent brightess of occulting body is G=16.4
Use an exposure time of 1.10 seconds with the standard RECON-QHY system.
SNR of 6.7 per integration for unocculted signal
Expected flux drop is 65% with SNR of 4.4 for the occulted depth (per occulted point)
Apparent velocity is 7.7 km/sec on the sky relative to the star, or, 7.8 arcsec/hr.
Position angle of asteroid motion is 149.9 degrees
The recommended exposure time corresponds to 8.5 km per image.
The 1-sigma error in the time of the event is 3.5 seconds.
The 1-sigma cross-track error in the shadow position is 33.1 km.
The sky-plane scale is 3568.9 km/arcsec.
Diameter estimates:
40.9 km assuming a 5% albedo, maximum of 5.3 sec for a central chord
16.7 km assuming a 30% albedo, maximum of 2.2 sec for a central chord
Cross-track diameter of 34.5 km used for deployment plan.
Star training set for 17172_99NZ41, (2026/10/16 02:03UT) Object RA Dec mag sep mel Betelgeuse 05:56:37.4 +07:24:35 0.4 12.54 159 Saiph 05:49:01.7 -09:39:44 2.1 14.55 142 PPM 176316 06:34:59.5 -01:14:33 5.1 0.56 148 PPM 176317 06:35:05.8 -00:17:13 8.3 0.39 149 PPM 176313 06:34:38.0 -00:35:47 9.7 0.13 148 17172_99NZ41 06:35:03.5 -00:40:44 16.4 148 Positions are for equinox of date
Star training set for 17172_99NZ41, (2026/10/16 02:03UT) Object RA Dec mag sep mel Betelgeuse 05:55:10.3 +07:24:26 0.4 12.54 159 Saiph 05:47:45.4 -09:40:11 2.1 14.55 142 PPM 176316 06:33:37.9 -01:13:13 5.1 0.56 148 PPM 176317 06:33:43.6 -00:15:53 8.3 0.39 149 PPM 176313 06:33:16.0 -00:34:28 9.7 0.13 148 17172_99NZ41 06:33:41.6 -00:39:24 16.4 148 Positions are for J2000