Occultation event with (9431) Pytho, event index number 3788
Regions able to see the event: NZ
Geocentric closest approach at 2026/06/12 09:05:51 UTC
J2000 position of star is 11:25:19.2 -03:39:43
Equinox of date position of star is 11:26:40.2 -03:48:27
Star is 131 degrees from the moon. Moon is 11% illuminated.
Stellar brightness G=15.6, apparent brightess of occulting body is G=16.5
Use an exposure time of 0.75 seconds with the standard RECON-QHY system.
SNR of 5.4 per integration for unocculted signal
Expected flux drop is 69% with SNR of 3.7 for the occulted depth (per occulted point)
Apparent velocity is 12.5 km/sec on the sky relative to the star, or, 11.5 arcsec/hr.
Position angle of asteroid motion is 76.6 degrees
The recommended exposure time corresponds to 9.3 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 36.1 km.
The sky-plane scale is 3895.6 km/arcsec.
Diameter estimates:
44.9 km assuming a 5% albedo, maximum of 3.6 sec for a central chord
18.3 km assuming a 30% albedo, maximum of 1.5 sec for a central chord
Cross-track diameter of 38.4 km used for deployment plan.
Star training set for 9431_Pytho, (2026/06/12 09:06UT) Object RA Dec mag sep mel Regulus 10:09:46.7 +11:50:13 1.3 24.70 107 4Gam Crv 12:17:10.2 -17:41:19 2.6 18.59 147 87 Leo 11:31:40.0 -03:08:59 4.8 1.41 132 PPM 194415 11:24:55.9 -03:26:08 8.5 0.57 131 PPM 194439 11:26:19.8 -03:53:19 9.8 0.12 131 9431_Pytho 11:26:40.2 -03:48:27 16.5 132 Positions are for equinox of date
Star training set for 9431_Pytho, (2026/06/12 09:06UT) Object RA Dec mag sep mel Regulus 10:08:21.9 +11:58:02 1.3 24.70 107 4Gam Crv 12:15:48.1 -17:32:30 2.6 18.59 147 87 Leo 11:30:18.9 -03:00:13 4.8 1.41 132 PPM 194415 11:23:34.9 -03:17:24 8.5 0.57 131 PPM 194439 11:24:58.8 -03:44:35 9.8 0.12 131 9431_Pytho 11:25:19.2 -03:39:43 16.5 131 Positions are for J2000