Occultation event with (5028) Halaesus, event index number 3660
Regions able to see the event: SAfrica
Geocentric closest approach at 2026/04/19 22:41:09 UTC
J2000 position of star is 12:22:49.2 +15:50:39
Equinox of date position of star is 12:24:09.0 +15:41:55
Star is 112 degrees from the moon. Moon is 9% illuminated.
Stellar brightness G=15.5, apparent brightess of occulting body is G=15.7
Use an exposure time of 0.80 seconds with the standard RECON-QHY system.
SNR of 6.0 per integration for unocculted signal
Expected flux drop is 54% with SNR of 3.2 for the occulted depth (per occulted point)
Apparent velocity is 15.8 km/sec on the sky relative to the star, or, 16.5 arcsec/hr.
Position angle of asteroid motion is 86.5 degrees
The recommended exposure time corresponds to 12.6 km per image.
The 1-sigma error in the time of the event is 1.2 seconds.
The 1-sigma cross-track error in the shadow position is 26.6 km.
The sky-plane scale is 3438.6 km/arcsec.
Diameter estimates:
53.0 km assuming a 5% albedo, maximum of 3.4 sec for a central chord
21.6 km assuming a 30% albedo, maximum of 1.4 sec for a central chord
Cross-track diameter of 50.8 km used for deployment plan.
Star training set for 5028_Halaesus, (2026/04/19 22:41UT) Object RA Dec mag sep mel Arcturus 14:16:51.8 +19:02:49 0.0 27.07 128 Denebola 11:50:24.0 +14:25:30 2.1 8.25 106 6 Com 12:17:20.2 +14:45:10 5.1 1.90 111 PPM 128976 12:22:08.6 +15:23:42 7.4 0.57 112 PPM 129019 12:25:14.4 +15:28:19 9.5 0.35 112 PPM 128999 12:24:00.7 +15:31:25 10.1 0.18 112 5028_Halaesus 12:24:09.0 +15:41:55 15.7 112 Positions are for equinox of date
Star training set for 5028_Halaesus, (2026/04/19 22:41UT) Object RA Dec mag sep mel Arcturus 14:15:37.7 +19:10:06 0.0 27.07 128 Denebola 11:49:02.7 +14:34:16 2.1 8.25 106 6 Com 12:16:00.0 +14:53:56 5.1 1.90 111 PPM 128976 12:20:48.6 +15:32:27 7.4 0.57 112 PPM 129019 12:23:54.6 +15:37:03 9.5 0.35 112 PPM 128999 12:22:40.9 +15:40:10 10.1 0.18 112 5028_Halaesus 12:22:49.2 +15:50:39 15.7 112 Positions are for J2000