Occultation event with (18054) 99SW7, event index number 4804
Regions able to see the event: Europe
Geocentric closest approach at 2026/11/21 19:49:33 UTC
J2000 position of star is 05:50:32.8 +07:12:18
Equinox of date position of star is 05:52:00.0 +07:12:39
Star is 68 degrees from the moon. Moon is 89% illuminated.
Stellar brightness G=14.5, apparent brightess of occulting body is G=15.9
Use an exposure time of 0.50 seconds with the standard RECON-QHY system.
SNR of 9.7 per integration for unocculted signal
Expected flux drop is 78% with SNR of 7.6 for the occulted depth (per occulted point)
Apparent velocity is 14.4 km/sec on the sky relative to the star, or, 16.0 arcsec/hr.
Position angle of asteroid motion is 87.3 degrees
The recommended exposure time corresponds to 7.2 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 32.6 km.
The sky-plane scale is 3248.2 km/arcsec.
Diameter estimates:
42.9 km assuming a 5% albedo, maximum of 3.0 sec for a central chord
17.5 km assuming a 30% albedo, maximum of 1.2 sec for a central chord
Cross-track diameter of 36.2 km used for deployment plan.
Star training set for 18054_99SW7, (2026/11/21 19:50UT) Object RA Dec mag sep mel Betelgeuse 05:56:37.7 +07:24:35 0.4 1.16 69 Bellatrix 05:26:34.5 +06:22:18 1.6 6.37 62 52 Ori 05:49:26.9 +06:27:41 5.5 0.98 68 PPM 149491 05:49:58.3 +07:33:30 7.4 0.61 68 PPM 149542 05:51:56.5 +07:07:53 9.5 0.08 68 18054_99SW7 05:52:00.0 +07:12:39 15.9 69 Positions are for equinox of date
Star training set for 18054_99SW7, (2026/11/21 19:50UT) Object RA Dec mag sep mel Betelgeuse 05:55:10.3 +07:24:26 0.4 1.16 69 Bellatrix 05:25:07.8 +06:20:58 1.6 6.37 62 52 Ori 05:48:00.2 +06:27:15 5.5 0.98 68 PPM 149491 05:48:30.9 +07:33:05 7.4 0.61 68 PPM 149542 05:50:29.3 +07:07:33 9.5 0.08 68 18054_99SW7 05:50:32.8 +07:12:18 15.9 68 Positions are for J2000