Occultation event with (4836) Medon, event index number 961
Regions able to see the event: SAfrica
Geocentric closest approach at 2025/05/09 17:42:32 UTC
J2000 position of star is 11:00:02.0 +29:08:45
Equinox of date position of star is 11:01:24.8 +29:00:34
Star is 47 degrees from the moon. Moon is 92% illuminated.
Stellar brightness G=16.4, apparent brightess of occulting body is G=14.8
Use an exposure time of 1.75 seconds with the standard RECON-QHY system.
SNR of 4.0 per integration for unocculted signal
Expected flux drop is 18% with SNR of 0.7 for the occulted depth (per occulted point)
Apparent velocity is 10.3 km/sec on the sky relative to the star, or, 11.4 arcsec/hr.
Position angle of asteroid motion is 272.9 degrees
The recommended exposure time corresponds to 18.0 km per image.
The 1-sigma error in the time of the event is 1.7 seconds.
The 1-sigma cross-track error in the shadow position is 52.4 km.
The sky-plane scale is 3241.0 km/arcsec.
Diameter estimates:
73.4 km assuming a 5% albedo, aximum of 7.1 sec for a central chord
30.0 km assuming a 30% albedo, maximum of 2.9 sec for a central chord
Cross-track diameter of 73.4 km used for deployment plan.
Star training set for 4836_Medon, (2025/05/09 17:43UT) Object RA Dec mag sep mel Regulus 10:09:43.2 +11:50:32 1.3 20.97 47 68Del Leo 11:15:27.2 +20:23:04 2.6 9.19 39 44 LMi 10:51:17.0 +27:50:22 6.0 2.52 48 PPM 100830 11:03:11.9 +29:44:04 8.2 0.82 48 PPM 100817 11:02:11.4 +29:04:55 8.6 0.18 47 4836_Medon 11:01:24.8 +29:00:34 14.8 47 Positions are for equinox of date
Star training set for 4836_Medon, (2025/05/09 17:43UT) Object RA Dec mag sep mel Regulus 10:08:21.9 +11:58:02 1.3 20.97 47 68Del Leo 11:14:06.7 +20:31:22 2.6 9.19 39 44 LMi 10:49:53.7 +27:58:27 6.0 2.52 48 PPM 100830 11:01:49.1 +29:52:16 8.2 0.82 48 PPM 100817 11:00:48.7 +29:13:07 8.6 0.18 47 4836_Medon 11:00:02.0 +29:08:45 14.8 47 Positions are for J2000