Occultation event with (3317) Paris, event index number 1312
Regions able to see the event: SAfrica
Geocentric closest approach at 2025/09/25 23:04:41 UTC
J2000 position of star is 04:23:02.8 -09:45:34
Equinox of date position of star is 04:24:16.6 -09:42:03
Star is 142 degrees from the moon. Moon is 15% illuminated.
Stellar brightness G=14.6, apparent brightess of occulting body is G=14.1
Use an exposure time of 0.70 seconds with the standard RECON-QHY system.
SNR of 9.7 per integration for unocculted signal
Expected flux drop is 38% with SNR of 3.7 for the occulted depth (per occulted point)
Apparent velocity is 11.9 km/sec on the sky relative to the star, or, 11.7 arcsec/hr.
Position angle of asteroid motion is 8.5 degrees
The recommended exposure time corresponds to 8.3 km per image.
The 1-sigma error in the time of the event is 2.8 seconds.
The 1-sigma cross-track error in the shadow position is 6.2 km.
The sky-plane scale is 3644.5 km/arcsec.
Diameter estimates:
125.3 km assuming a 5% albedo, aximum of 10.5 sec for a central chord
51.2 km assuming a 30% albedo, maximum of 4.3 sec for a central chord
Cross-track diameter of 118.8 km used for deployment plan.
Star training set for 3317_Paris, (2025/09/25 23:05UT) Object RA Dec mag sep mel Rigel 05:15:46.6 -08:10:26 0.1 12.81 135 67Bet Eri 05:09:07.0 -05:03:18 2.8 12.05 139 39 Eri 04:15:37.3 -10:11:40 4.2 2.19 143 PPM 186841 04:23:17.3 -09:53:35 8.2 0.31 142 PPM 186844 04:23:24.0 -09:33:27 9.5 0.26 143 3317_Paris 04:24:16.6 -09:42:03 14.1 142 Positions are for equinox of date
Star training set for 3317_Paris, (2025/09/25 23:05UT) Object RA Dec mag sep mel Rigel 05:14:32.3 -08:12:06 0.1 12.81 135 67Bet Eri 05:07:50.8 -05:05:13 2.8 12.05 139 39 Eri 04:14:23.7 -10:15:28 4.2 2.19 143 PPM 186841 04:22:03.7 -09:57:08 8.2 0.31 142 PPM 186844 04:22:10.1 -09:36:59 9.5 0.26 143 3317_Paris 04:23:02.8 -09:45:34 14.1 142 Positions are for J2000