Occultation event with (31342) 98MU31, event index number 1410
Regions able to see the event: Senegal
Geocentric closest approach at 2025/10/24 22:14:28 UTC
J2000 position of star is 03:41:47.2 -05:45:34
Equinox of date position of star is 03:43:03.7 -05:40:42
Star is 146 degrees from the moon. Moon is 10% illuminated.
Stellar brightness G=15.8, apparent brightess of occulting body is G=15.6
Use an exposure time of 0.70 seconds with the standard RECON-QHY system.
SNR of 4.2 per integration for unocculted signal
Expected flux drop is 45% with SNR of 1.9 for the occulted depth (per occulted point)
Apparent velocity is 16.1 km/sec on the sky relative to the star, or, 17.9 arcsec/hr.
Position angle of asteroid motion is 73.0 degrees
The recommended exposure time corresponds to 11.3 km per image.
The 1-sigma error in the time of the event is 1.6 seconds.
The 1-sigma cross-track error in the shadow position is 24.4 km.
The sky-plane scale is 3233.8 km/arcsec.
Diameter estimates:
49.0 km assuming a 5% albedo, aximum of 3.0 sec for a central chord
20.0 km assuming a 30% albedo, maximum of 1.2 sec for a central chord
Cross-track diameter of 47.4 km used for deployment plan.
Star training set for 31342_98MU31, (2025/10/24 22:14UT) Object RA Dec mag sep mel Rigel 05:15:46.8 -08:10:25 0.1 23.14 143 Menkar 03:03:37.9 +04:11:22 2.5 13.94 150 22 Eri 03:41:55.1 -05:07:44 5.5 0.62 146 21 Eri 03:40:17.7 -05:32:43 6.2 0.70 146 PPM 186074 03:42:33.0 -05:35:59 9.0 0.15 146 31342_98MU31 03:43:03.7 -05:40:42 15.6 146 Positions are for equinox of date
Star training set for 31342_98MU31, (2025/10/24 22:14UT) Object RA Dec mag sep mel Rigel 05:14:32.3 -08:12:06 0.1 23.14 143 Menkar 03:02:16.8 +04:05:21 2.5 13.94 150 22 Eri 03:40:38.3 -05:12:38 5.5 0.62 146 21 Eri 03:39:01.1 -05:37:40 6.2 0.70 146 PPM 186074 03:41:16.4 -05:40:52 9.0 0.15 146 31342_98MU31 03:41:47.2 -05:45:34 15.6 146 Positions are for J2000