Occultation event with (4068) Menestheus, event index number 1046
Regions able to see the event: SAmericaN
Geocentric closest approach at 2025/06/10 21:42:38 UTC
J2000 position of star is 08:49:35.1 +08:07:58
Equinox of date position of star is 08:50:56.9 +08:02:14
Star is 121 degrees from the moon. Moon is 100% illuminated.
Stellar brightness G=16.1, apparent brightess of occulting body is G=15.1
Use an exposure time of 0.70 seconds with the standard RECON-QHY system.
SNR of 3.0 per integration for unocculted signal
Expected flux drop is 28% with SNR of 0.8 for the occulted depth (per occulted point)
Apparent velocity is 32.0 km/sec on the sky relative to the star, or, 30.1 arcsec/hr.
Position angle of asteroid motion is 353.1 degrees
The recommended exposure time corresponds to 22.4 km per image.
The 1-sigma error in the time of the event is 1.5 seconds.
The 1-sigma cross-track error in the shadow position is 6.5 km.
The sky-plane scale is 3833.7 km/arcsec.
Diameter estimates:
71.1 km assuming a 5% albedo, aximum of 2.2 sec for a central chord
29.0 km assuming a 30% albedo, maximum of 0.9 sec for a central chord
Cross-track diameter of 71.1 km used for deployment plan.
Star training set for 4068_Menestheus, (2025/06/10 21:43UT) Object RA Dec mag sep mel Regulus 10:09:43.5 +11:50:31 1.3 19.76 106 Alphard 09:28:50.3 -08:46:12 2.0 19.28 105 49 Cnc 08:46:07.7 +09:59:17 5.5 2.29 123 PPM 155114 08:53:38.4 +07:57:51 7.4 0.67 121 PPM 155067 08:51:23.7 +08:10:41 9.0 0.18 121 4068_Menestheu 08:50:56.9 +08:02:14 15.1 121 Positions are for equinox of date
Star training set for 4068_Menestheus, (2025/06/10 21:43UT) Object RA Dec mag sep mel Regulus 10:08:21.9 +11:58:02 1.3 19.76 106 Alphard 09:27:35.2 -08:39:30 2.0 19.28 105 49 Cnc 08:44:45.0 +10:04:54 5.5 2.29 123 PPM 155114 08:52:16.7 +08:03:40 7.4 0.67 121 PPM 155067 08:50:01.9 +08:16:26 9.0 0.18 121 4068_Menestheu 08:49:35.1 +08:07:58 15.1 121 Positions are for J2000