Occultation event with (48438) 89WJ2, event index number 4297
Regions able to see the event: SAmericaN
Geocentric closest approach at 2026/09/24 05:55:04 UTC
J2000 position of star is 06:47:34.2 +19:28:53
Equinox of date position of star is 06:49:08.8 +19:27:01
Star is 130 degrees from the moon. Moon is 93% illuminated.
Stellar brightness G=15.3, apparent brightess of occulting body is G=16.5
Use an exposure time of 0.50 seconds with the standard RECON-QHY system.
SNR of 5.2 per integration for unocculted signal
Expected flux drop is 74% with SNR of 3.9 for the occulted depth (per occulted point)
Apparent velocity is 16.7 km/sec on the sky relative to the star, or, 16.1 arcsec/hr.
Position angle of asteroid motion is 76.4 degrees
The recommended exposure time corresponds to 8.4 km per image.
The 1-sigma error in the time of the event is 1.3 seconds.
The 1-sigma cross-track error in the shadow position is 25.4 km.
The sky-plane scale is 3744.2 km/arcsec.
Diameter estimates:
40.2 km assuming a 5% albedo, maximum of 2.4 sec for a central chord
16.4 km assuming a 30% albedo, maximum of 1.0 sec for a central chord
Cross-track diameter of 36.1 km used for deployment plan.
Star training set for 48438_89WJ2, (2026/09/24 05:55UT) Object RA Dec mag sep mel Pollux 07:46:56.9 +27:57:34 1.1 15.71 141 Alhena 06:39:15.3 +16:22:27 1.9 3.87 127 PPM 123009 06:47:55.2 +18:48:27 6.5 0.70 130 PPM 123044 06:49:07.5 +18:54:38 8.3 0.54 130 PPM 123025 06:48:32.6 +19:31:44 9.3 0.16 130 48438_89WJ2 06:49:08.8 +19:27:01 16.5 130 Positions are for equinox of date
Star training set for 48438_89WJ2, (2026/09/24 05:55UT) Object RA Dec mag sep mel Pollux 07:45:17.7 +28:01:33 1.1 15.71 141 Alhena 06:37:42.8 +16:23:56 1.9 3.87 127 PPM 123009 06:46:21.1 +18:50:16 6.5 0.70 130 PPM 123044 06:47:33.3 +18:56:31 8.3 0.54 130 PPM 123025 06:46:58.0 +19:33:35 9.3 0.16 130 48438_89WJ2 06:47:34.2 +19:28:53 16.5 130 Positions are for J2000