Occultation event with (4007) Euryalos, event index number 1126
Regions able to see the event: SAmericaN
Geocentric closest approach at 2025/07/11 00:26:18 UTC
J2000 position of star is 10:48:45.1 +10:58:58
Equinox of date position of star is 10:50:05.6 +10:50:50
Star is 132 degrees from the moon. Moon is 100% illuminated.
Stellar brightness G=14.5, apparent brightess of occulting body is G=16.1
Use an exposure time of 0.40 seconds with the standard RECON-QHY system.
SNR of 8.5 per integration for unocculted signal
Expected flux drop is 81% with SNR of 6.9 for the occulted depth (per occulted point)
Apparent velocity is 31.7 km/sec on the sky relative to the star, or, 27.5 arcsec/hr.
The recommended exposure time corresponds to 12.7 km per image.
The 1-sigma error in the time of the event is 1.8 seconds.
The 1-sigma cross-track error in the shadow position is 43.4 km.
The sky-plane scale is 4145.5 km/arcsec.
Diameter estimates:
51.3 km assuming a 5% albedo, aximum of 1.6 sec for a central chord
20.9 km assuming a 30% albedo, maximum of 0.7 sec for a central chord
Cross-track diameter of 51.3 km used for deployment plan.
Star training set for 4007_Euryalos, (2025/07/11 00:26UT) Object RA Dec mag sep mel Regulus 10:09:43.7 +11:50:29 1.3 9.94 141 53 Leo 10:50:35.8 +10:24:34 5.3 0.45 131 PPM 127689 10:47:57.2 +11:02:54 8.5 0.56 132 PPM 127749 10:51:34.7 +10:56:46 9.9 0.38 131 PPM 127734 10:50:50.3 +10:55:45 11.5 0.20 131 4007_Euryalos 10:50:05.6 +10:50:50 16.1 131 Positions are for equinox of date
Star training set for 4007_Euryalos, (2025/07/11 00:26UT) Object RA Dec mag sep mel Regulus 10:08:21.9 +11:58:02 1.3 9.94 141 53 Leo 10:49:15.4 +10:32:42 5.3 0.45 131 PPM 127689 10:46:36.6 +11:11:00 8.5 0.56 132 PPM 127749 10:50:14.2 +11:04:54 9.9 0.38 131 PPM 127734 10:49:29.8 +11:03:53 11.5 0.20 131 4007_Euryalos 10:48:45.1 +10:58:58 16.1 132 Positions are for J2000