Occultation event with (17172) 99NZ41, event index number 4815
Regions able to see the event: SAmericaN,SAmericaS
Geocentric closest approach at 2026/11/22 07:56:58 UTC
J2000 position of star is 06:28:41.8 -01:53:24
Equinox of date position of star is 06:30:03.3 -01:54:33
Star is 73 degrees from the moon. Moon is 93% illuminated.
Stellar brightness G=14.6, apparent brightess of occulting body is G=16.1
Use an exposure time of 0.50 seconds with the standard RECON-QHY system.
SNR of 9.6 per integration for unocculted signal
Expected flux drop is 80% with SNR of 7.7 for the occulted depth (per occulted point)
Apparent velocity is 12.4 km/sec on the sky relative to the star, or, 13.7 arcsec/hr.
Position angle of asteroid motion is 80.9 degrees
The recommended exposure time corresponds to 6.2 km per image.
The 1-sigma error in the time of the event is 1.7 seconds.
The 1-sigma cross-track error in the shadow position is 37.7 km.
The sky-plane scale is 3255.1 km/arcsec.
Diameter estimates:
40.9 km assuming a 5% albedo, maximum of 3.3 sec for a central chord
16.7 km assuming a 30% albedo, maximum of 1.4 sec for a central chord
Cross-track diameter of 34.5 km used for deployment plan.
Star training set for 17172_99NZ41, (2026/11/22 07:57UT) Object RA Dec mag sep mel Betelgeuse 05:56:37.7 +07:24:35 0.4 12.50 63 Saiph 05:49:02.0 -09:39:44 2.1 12.81 66 PPM 176266 06:28:01.3 -01:31:31 5.9 0.64 73 PPM 176283 06:29:57.6 -01:36:30 7.8 0.30 73 PPM 176288 06:30:52.5 -01:46:34 9.4 0.24 74 PPM 176282 06:29:49.8 -01:46:50 10.2 0.14 73 17172_99NZ41 06:30:03.3 -01:54:33 16.1 74 Positions are for equinox of date
Star training set for 17172_99NZ41, (2026/11/22 07:57UT) Object RA Dec mag sep mel Betelgeuse 05:55:10.3 +07:24:26 0.4 12.50 63 Saiph 05:47:45.4 -09:40:11 2.1 12.81 66 PPM 176266 06:26:39.6 -01:30:27 5.9 0.64 73 PPM 176283 06:28:35.9 -01:35:22 7.8 0.30 73 PPM 176288 06:29:30.9 -01:45:23 9.4 0.24 74 PPM 176282 06:28:28.2 -01:45:42 10.2 0.14 73 17172_99NZ41 06:28:41.8 -01:53:24 16.1 73 Positions are for J2000