Occultation event with (9431) Pytho, event index number 3413
Regions able to see the event: Europe
Geocentric closest approach at 2026/03/13 00:39:38 UTC
J2000 position of star is 11:39:09.1 -09:35:47
Equinox of date position of star is 11:40:29.2 -09:44:30
Star is 100 degrees from the moon. Moon is 35% illuminated.
Stellar brightness G=14.1, apparent brightess of occulting body is G=15.7
Use an exposure time of 0.30 seconds with the standard RECON-QHY system.
SNR of 9.7 per integration for unocculted signal
Expected flux drop is 81% with SNR of 7.9 for the occulted depth (per occulted point)
Apparent velocity is 18.5 km/sec on the sky relative to the star, or, 20.3 arcsec/hr.
Position angle of asteroid motion is 124.3 degrees
The recommended exposure time corresponds to 5.5 km per image.
The 1-sigma error in the time of the event is 1.2 seconds.
The 1-sigma cross-track error in the shadow position is 28.8 km.
The sky-plane scale is 3268.8 km/arcsec.
Diameter estimates:
44.9 km assuming a 5% albedo, maximum of 2.4 sec for a central chord
18.3 km assuming a 30% albedo, maximum of 1.0 sec for a central chord
Cross-track diameter of 38.4 km used for deployment plan.
Star training set for 9431_Pytho, (2026/03/13 00:40UT) Object RA Dec mag sep mel Spica 13:26:34.6 -11:17:50 1.0 26.11 76 4Gam Crv 12:17:09.4 -17:41:14 2.6 11.93 88 21The Crt 11:38:00.8 -09:56:50 4.7 0.64 101 PPM 194687 11:40:59.5 -09:36:41 7.6 0.18 100 PPM 194677 11:40:26.4 -09:42:52 9.4 0.03 100 9431_Pytho 11:40:29.2 -09:44:30 15.7 100 Positions are for equinox of date
Star training set for 9431_Pytho, (2026/03/13 00:40UT) Object RA Dec mag sep mel Spica 13:25:11.5 -11:09:41 1.0 26.11 76 4Gam Crv 12:15:48.1 -17:32:30 2.6 11.93 88 21The Crt 11:36:40.8 -09:48:08 4.7 0.64 101 PPM 194687 11:39:39.5 -09:27:58 7.6 0.18 100 PPM 194677 11:39:06.4 -09:34:09 9.4 0.03 100 9431_Pytho 11:39:09.1 -09:35:47 15.7 100 Positions are for J2000