Occultation event with (11554) Asios, event index number 3290
Regions able to see the event: SAfrica
Geocentric closest approach at 2026/02/22 18:12:01 UTC
J2000 position of star is 03:08:19.2 +04:32:57
Equinox of date position of star is 03:09:41.6 +04:38:53
Star is 18 degrees from the moon. Moon is 30% illuminated.
Stellar brightness G=16.0, apparent brightess of occulting body is G=16.5
Use an exposure time of 0.55 seconds with the standard RECON-QHY system.
SNR of 3.2 per integration for unocculted signal
Expected flux drop is 61% with SNR of 2.0 for the occulted depth (per occulted point)
Apparent velocity is 22.0 km/sec on the sky relative to the star, or, 18.8 arcsec/hr.
Position angle of asteroid motion is 56.2 degrees
The recommended exposure time corresponds to 12.1 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 19.7 km.
The sky-plane scale is 4215.1 km/arcsec.
Diameter estimates:
48.1 km assuming a 5% albedo, maximum of 2.2 sec for a central chord
19.6 km assuming a 30% albedo, maximum of 0.9 sec for a central chord
Cross-track diameter of 41.6 km used for deployment plan.
Star training set for 11554_Asios, (2026/02/22 18:12UT) Object RA Dec mag sep mel Aldebaran 04:37:25.4 +16:33:35 0.8 24.59 31 Menkar 03:03:39.0 +04:11:27 2.5 1.57 18 93 Cet 03:03:44.9 +04:27:16 5.4 1.49 17 PPM 146238 03:07:44.7 +03:54:35 7.7 0.88 18 PPM 146248 03:08:05.4 +04:17:45 9.6 0.53 18 PPM 146293 03:11:01.4 +04:28:57 10.6 0.37 18 11554_Asios 03:09:41.6 +04:38:53 16.5 18 Positions are for equinox of date
Star training set for 11554_Asios, (2026/02/22 18:12UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 24.59 31 Menkar 03:02:16.8 +04:05:21 2.5 1.57 18 93 Cet 03:02:22.6 +04:21:11 5.4 1.49 17 PPM 146238 03:06:22.6 +03:48:36 7.7 0.88 18 PPM 146248 03:06:43.1 +04:11:46 9.6 0.53 18 PPM 146293 03:09:39.0 +04:23:04 10.6 0.37 18 11554_Asios 03:08:19.2 +04:32:57 16.5 18 Positions are for J2000