Occultation event with (31342) 98MU31, event index number 4409
Regions able to see the event: Australia
Geocentric closest approach at 2026/10/15 20:35:18 UTC
J2000 position of star is 05:36:46.2 +09:53:13
Equinox of date position of star is 05:38:14.8 +09:54:06
Star is 162 degrees from the moon. Moon is 25% illuminated.
Stellar brightness G=8.3, apparent brightess of occulting body is G=16.1
Use an exposure time of 0.12 seconds with the standard RECON-QHY system.
SNR of 90.7 per integration for unocculted signal
Expected flux drop is 100% with SNR of 90.6 for the occulted depth (per occulted point)
Apparent velocity is 3.6 km/sec on the sky relative to the star, or, 3.6 arcsec/hr.
Position angle of asteroid motion is 69.2 degrees
The recommended exposure time corresponds to 0.4 km per image.
The 1-sigma error in the time of the event is 7.3 seconds.
The 1-sigma cross-track error in the shadow position is 24.9 km.
The sky-plane scale is 3606.7 km/arcsec.
Diameter estimates:
49.0 km assuming a 5% albedo, maximum of 13.7 sec for a central chord
20.0 km assuming a 30% albedo, maximum of 5.6 sec for a central chord
Cross-track diameter of 47.4 km used for deployment plan.
Star training set for 31342_98MU31, (2026/10/15 20:35UT) Object RA Dec mag sep mel Betelgeuse 05:56:37.4 +07:24:35 0.4 5.18 158 Bellatrix 05:26:34.2 +06:22:18 1.6 4.56 158 PPM 149168 05:36:41.2 +09:37:44 6.3 0.47 162 PPM 149255 05:39:44.3 +09:54:44 8.4 0.37 162 PPM 149212 05:38:04.1 +09:52:49 9.0 0.05 162 31342_98MU31 05:38:14.8 +09:54:06 16.1 162 Positions are for equinox of date
Star training set for 31342_98MU31, (2026/10/15 20:35UT) Object RA Dec mag sep mel Betelgeuse 05:55:10.3 +07:24:26 0.4 5.18 158 Bellatrix 05:25:07.8 +06:20:58 1.6 4.56 158 PPM 149168 05:35:12.8 +09:36:48 6.3 0.47 162 PPM 149255 05:38:15.7 +09:53:55 8.4 0.37 162 PPM 149212 05:36:35.5 +09:51:56 9.0 0.05 162 31342_98MU31 05:36:46.2 +09:53:13 16.1 162 Positions are for J2000