Occultation event with (48438) 89WJ2, event index number 1253
Regions able to see the event: Europe
Geocentric closest approach at 2025/08/27 04:01:57 UTC
J2000 position of star is 04:49:12.7 +02:12:55
Equinox of date position of star is 04:50:32.8 +02:15:30
Star is 124 degrees from the moon. Moon is 15% illuminated.
Stellar brightness G=15.2, apparent brightess of occulting body is G=16.4
Use an exposure time of 0.55 seconds with the standard RECON-QHY system.
SNR of 6.1 per integration for unocculted signal
Expected flux drop is 75% with SNR of 4.6 for the occulted depth (per occulted point)
Apparent velocity is 15.3 km/sec on the sky relative to the star, or, 15.1 arcsec/hr.
Position angle of asteroid motion is 96.0 degrees
The recommended exposure time corresponds to 8.4 km per image.
The 1-sigma error in the time of the event is 1.0 seconds.
The 1-sigma cross-track error in the shadow position is 27.7 km.
The sky-plane scale is 3649.0 km/arcsec.
Diameter estimates:
40.2 km assuming a 5% albedo, aximum of 2.6 sec for a central chord
16.4 km assuming a 30% albedo, maximum of 1.1 sec for a central chord
Cross-track diameter of 36.1 km used for deployment plan.
Star training set for 48438_89WJ2, (2025/08/27 04:02UT) Object RA Dec mag sep mel Rigel 05:15:46.3 -08:10:26 0.1 12.18 116 67Bet Eri 05:09:06.7 -05:03:19 2.8 8.66 118 8Pi 5Ori 04:55:35.4 +02:28:50 3.7 1.28 123 PPM 148018 04:50:53.4 +02:14:41 7.6 0.09 124 48438_89WJ2 04:50:32.8 +02:15:30 16.4 124 Positions are for equinox of date
Star training set for 48438_89WJ2, (2025/08/27 04:02UT) Object RA Dec mag sep mel Rigel 05:14:32.3 -08:12:06 0.1 12.18 116 67Bet Eri 05:07:50.8 -05:05:13 2.8 8.66 118 8Pi 5Ori 04:54:15.1 +02:26:26 3.7 1.28 123 PPM 148018 04:49:33.3 +02:12:07 7.6 0.09 124 48438_89WJ2 04:49:12.7 +02:12:55 16.4 124 Positions are for J2000