Occultation event with (4946) Askalaphus, event index number 1567
Regions able to see the event: SAmericaN
Geocentric closest approach at 2025/11/22 07:49:06 UTC
J2000 position of star is 11:07:39.5 +29:19:08
Equinox of date position of star is 11:09:03.4 +29:10:42
Star is 107 degrees from the moon. Moon is 4% illuminated.
Stellar brightness G=10.1, apparent brightess of occulting body is G=16.0
Use an exposure time of 0.12 seconds with the standard RECON-QHY system.
SNR of 54.0 per integration for unocculted signal
Expected flux drop is 100% with SNR of 53.8 for the occulted depth (per occulted point)
Apparent velocity is 18.7 km/sec on the sky relative to the star, or, 17.1 arcsec/hr.
Position angle of asteroid motion is 80.3 degrees
The recommended exposure time corresponds to 2.2 km per image.
The 1-sigma error in the time of the event is 0.5 seconds.
The 1-sigma cross-track error in the shadow position is 32.4 km.
The sky-plane scale is 3946.3 km/arcsec.
Diameter estimates:
56.0 km assuming a 5% albedo, maximum of 3.0 sec for a central chord
22.9 km assuming a 30% albedo, maximum of 1.2 sec for a central chord
Cross-track diameter of 48.2 km used for deployment plan.
Star training set for 4946_Askalaphus, (2025/11/22 07:49UT) Object RA Dec mag sep mel Regulus 10:09:44.9 +11:50:23 1.3 22.16 113 68Del Leo 11:15:28.9 +20:22:53 2.6 8.92 102 44 LMi 10:51:18.8 +27:50:12 6.0 4.12 110 PPM 075703 11:10:26.5 +29:53:59 8.2 0.78 107 PPM 100924 11:09:54.3 +29:10:27 9.9 0.18 107 PPM 100913 11:09:03.4 +29:10:41 11.5 0.00 107 4946_Askalaphu 11:09:03.4 +29:10:42 16.0 107 Positions are for equinox of date
Star training set for 4946_Askalaphus, (2025/11/22 07:49UT) Object RA Dec mag sep mel Regulus 10:08:21.9 +11:58:02 1.3 22.16 113 68Del Leo 11:14:06.7 +20:31:22 2.6 8.92 102 44 LMi 10:49:53.7 +27:58:27 6.0 4.12 110 PPM 075703 11:09:02.5 +30:02:25 8.2 0.78 107 PPM 100924 11:08:30.4 +29:18:53 9.9 0.18 107 PPM 100913 11:07:39.4 +29:19:07 11.5 0.00 107 4946_Askalaphu 11:07:39.5 +29:19:08 16.0 107 Positions are for J2000