Occultation event with (23135) Pheidas, event index number 817
Regions able to see the event: Europe
Geocentric closest approach at 2025/03/16 18:41:29 UTC
J2000 position of star is 09:44:50.4 -08:36:32
Equinox of date position of star is 09:46:05.1 -08:43:32
Star is 54 degrees from the moon. Moon is 94% illuminated.
Stellar brightness G=16.0, apparent brightess of occulting body is G=14.9
Use an exposure time of 1.00 seconds with the standard RECON-QHY system.
SNR of 4.3 per integration for unocculted signal
Expected flux drop is 27% with SNR of 1.2 for the occulted depth (per occulted point)
Apparent velocity is 14.2 km/sec on the sky relative to the star, or, 17.1 arcsec/hr.
The recommended exposure time corresponds to 14.2 km per image.
The 1-sigma error in the time of the event is 2.2 seconds.
The 1-sigma cross-track error in the shadow position is 27.5 km.
The sky-plane scale is 2994.2 km/arcsec.
Diameter estimates:
59.2 km assuming a 5% albedo, aximum of 4.2 sec for a central chord
24.1 km assuming a 30% albedo, maximum of 1.7 sec for a central chord
Cross-track diameter of 59.2 km used for deployment plan.
Star training set for 23135_Pheidas, (2025/03/16 18:41UT) Object RA Dec mag sep mel Regulus 10:09:42.7 +11:50:35 1.3 21.39 54 Alphard 09:28:49.6 -08:46:09 2.0 4.26 58 8Gam Sex 09:53:45.3 -08:13:29 4.8 1.96 52 PPM 192703 09:46:40.0 -08:35:59 7.6 0.19 54 23135_Pheidas 09:46:05.1 -08:43:32 14.9 54 Positions are for equinox of date
Star training set for 23135_Pheidas, (2025/03/16 18:41UT) Object RA Dec mag sep mel Regulus 10:08:21.9 +11:58:02 1.3 21.39 54 Alphard 09:27:35.2 -08:39:30 2.0 4.26 58 8Gam Sex 09:52:30.3 -08:06:19 4.8 1.96 52 PPM 192703 09:45:25.3 -08:28:58 7.6 0.19 54 23135_Pheidas 09:44:50.4 -08:36:32 14.9 54 Positions are for J2000