Occultation event with (1172) Aneas, event index number 5177
Regions able to see the event: SAfrica
Geocentric closest approach at 2026/12/11 22:36:31 UTC
J2000 position of star is 05:49:22.9 +16:46:05
Equinox of date position of star is 05:50:56.6 +16:46:28
Star is 154 degrees from the moon. Moon is 7% illuminated.
Stellar brightness G=16.4, apparent brightess of occulting body is G=13.3
Use an exposure time of 1.95 seconds with the standard RECON-QHY system.
SNR of 3.0 per integration for unocculted signal
Expected flux drop is 6% with SNR of 0.2 for the occulted depth (per occulted point)
Apparent velocity is 18.9 km/sec on the sky relative to the star, or, 19.9 arcsec/hr.
Position angle of asteroid motion is 77.8 degrees
The recommended exposure time corresponds to 36.8 km per image.
The 1-sigma error in the time of the event is 0.1 seconds.
The 1-sigma cross-track error in the shadow position is 33.8 km.
The sky-plane scale is 3416.9 km/arcsec.
Diameter estimates:
138.7 km assuming a 5% albedo, maximum of 7.3 sec for a central chord
56.6 km assuming a 30% albedo, maximum of 3.0 sec for a central chord
Cross-track diameter of 118.0 km used for deployment plan.
Star training set for 1172_Aneas, (2026/12/11 22:37UT) Object RA Dec mag sep mel Betelgeuse 05:56:37.9 +07:24:35 0.4 9.47 151 Alhena 06:39:16.1 +16:22:26 1.9 11.58 165 126 Tau 05:42:51.2 +16:32:44 4.6 1.95 152 PPM 121438 05:51:03.9 +17:31:29 8.3 0.75 155 PPM 121416 05:49:57.2 +16:58:29 9.9 0.31 154 PPM 121453 05:51:51.3 +16:34:41 10.4 0.29 154 1172_Aneas 05:50:56.6 +16:46:28 13.3 155 Positions are for equinox of date
Star training set for 1172_Aneas, (2026/12/11 22:37UT) Object RA Dec mag sep mel Betelgeuse 05:55:10.3 +07:24:26 0.4 9.47 151 Alhena 06:37:42.8 +16:23:56 1.9 11.58 165 126 Tau 05:41:17.7 +16:32:01 4.6 1.95 152 PPM 121438 05:49:29.7 +17:31:06 8.3 0.75 155 PPM 121416 05:48:23.4 +16:58:03 9.9 0.31 154 PPM 121453 05:50:17.7 +16:34:20 10.4 0.29 154 1172_Aneas 05:49:22.9 +16:46:05 13.3 154 Positions are for J2000