Occultation event with (1583) Antilochus, event index number 3551
Regions able to see the event: Australia
Geocentric closest approach at 2026/03/31 14:13:47 UTC
J2000 position of star is 12:58:57.9 -21:17:36
Equinox of date position of star is 13:00:22.2 -21:26:04
Star is 31 degrees from the moon. Moon is 98% illuminated.
Stellar brightness G=15.0, apparent brightess of occulting body is G=13.6
Use an exposure time of 1.45 seconds with the standard RECON-QHY system.
SNR of 9.2 per integration for unocculted signal
Expected flux drop is 21% with SNR of 1.9 for the occulted depth (per occulted point)
Apparent velocity is 18.4 km/sec on the sky relative to the star, or, 20.7 arcsec/hr.
Position angle of asteroid motion is 126.4 degrees
The recommended exposure time corresponds to 26.7 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 29.5 km.
The sky-plane scale is 3203.4 km/arcsec.
Diameter estimates:
116.4 km assuming a 5% albedo, maximum of 6.3 sec for a central chord
47.5 km assuming a 30% albedo, maximum of 2.6 sec for a central chord
Cross-track diameter of 108.8 km used for deployment plan.
Star training set for 1583_Antilochus, (2026/03/31 14:14UT) Object RA Dec mag sep mel Spica 13:26:34.8 -11:17:51 1.0 11.92 31 9Bet Crv 12:35:46.3 -23:32:30 2.6 6.06 29 PPM 261160 13:05:10.7 -20:43:25 5.5 1.33 31 PPM 261108 13:02:22.1 -21:34:02 8.0 0.48 31 PPM 261065 13:00:11.5 -21:14:05 9.2 0.20 31 1583_Antilochu 13:00:22.2 -21:26:04 13.6 31 Positions are for equinox of date
Star training set for 1583_Antilochus, (2026/03/31 14:14UT) Object RA Dec mag sep mel Spica 13:25:11.5 -11:09:41 1.0 11.92 31 9Bet Crv 12:34:23.2 -23:23:50 2.6 6.06 29 PPM 261160 13:03:46.4 -20:35:00 5.5 1.33 31 PPM 261108 13:00:57.7 -21:25:35 8.0 0.48 31 PPM 261065 12:58:47.3 -21:05:36 9.2 0.20 31 1583_Antilochu 12:58:57.9 -21:17:36 13.6 31 Positions are for J2000