Occultation event with (1583) Antilochus, event index number 3644
Regions able to see the event: SAmericaS
Geocentric closest approach at 2026/04/17 02:15:47 UTC
J2000 position of star is 12:51:09.1 -19:47:37
Equinox of date position of star is 12:52:32.8 -19:56:10
Star is 170 degrees from the moon. Moon is 0% illuminated.
Stellar brightness G=14.5, apparent brightess of occulting body is G=13.5
Use an exposure time of 0.75 seconds with the standard RECON-QHY system.
SNR of 9.9 per integration for unocculted signal
Expected flux drop is 29% with SNR of 2.9 for the occulted depth (per occulted point)
Apparent velocity is 19.3 km/sec on the sky relative to the star, or, 21.8 arcsec/hr.
Position angle of asteroid motion is 132.5 degrees
The recommended exposure time corresponds to 14.5 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 26.7 km.
The sky-plane scale is 3194.3 km/arcsec.
Diameter estimates:
116.4 km assuming a 5% albedo, maximum of 6.0 sec for a central chord
47.5 km assuming a 30% albedo, maximum of 2.5 sec for a central chord
Cross-track diameter of 108.8 km used for deployment plan.
Star training set for 1583_Antilochus, (2026/04/17 02:16UT) Object RA Dec mag sep mel Spica 13:26:34.9 -11:17:52 1.0 11.90 177 9Bet Crv 12:35:46.4 -23:32:30 2.6 5.31 165 PPM 226209 12:43:12.3 -19:54:10 6.1 2.20 169 PPM 226490 12:54:53.1 -20:00:58 8.5 0.56 170 PPM 226437 12:52:28.0 -19:59:04 9.6 0.05 170 1583_Antilochu 12:52:32.8 -19:56:10 13.5 170 Positions are for equinox of date
Star training set for 1583_Antilochus, (2026/04/17 02:16UT) Object RA Dec mag sep mel Spica 13:25:11.5 -11:09:41 1.0 11.90 177 9Bet Crv 12:34:23.2 -23:23:50 2.6 5.31 165 PPM 226209 12:41:49.1 -19:45:32 6.1 2.20 169 PPM 226490 12:53:29.3 -19:52:26 8.5 0.56 170 PPM 226437 12:51:04.3 -19:50:31 9.6 0.05 170 1583_Antilochu 12:51:09.1 -19:47:37 13.5 170 Positions are for J2000