Occultation event with (4007) Euryalos, event index number 3890
Regions able to see the event: NZ
Geocentric closest approach at 2026/07/26 06:30:39 UTC
J2000 position of star is 12:29:18.2 -05:35:06
Equinox of date position of star is 12:30:40.3 -05:43:53
Star is 77 degrees from the moon. Moon is 90% illuminated.
Stellar brightness G=13.0, apparent brightess of occulting body is G=16.2
Use an exposure time of 0.12 seconds with the standard RECON-QHY system.
SNR of 11.3 per integration for unocculted signal
Expected flux drop is 95% with SNR of 10.7 for the occulted depth (per occulted point)
Apparent velocity is 24.6 km/sec on the sky relative to the star, or, 21.7 arcsec/hr.
Position angle of asteroid motion is 116.6 degrees
The recommended exposure time corresponds to 3.0 km per image.
The 1-sigma error in the time of the event is 1.3 seconds.
The 1-sigma cross-track error in the shadow position is 17.6 km.
The sky-plane scale is 4081.5 km/arcsec.
Diameter estimates:
51.8 km assuming a 5% albedo, maximum of 2.1 sec for a central chord
21.1 km assuming a 30% albedo, maximum of 0.9 sec for a central chord
Cross-track diameter of 45.5 km used for deployment plan.
Star training set for 4007_Euryalos, (2026/07/26 06:31UT) Object RA Dec mag sep mel Spica 13:26:35.8 -11:17:57 1.0 14.90 63 4Gam Crv 12:17:10.6 -17:41:21 2.6 12.40 75 PPM 195577 12:33:00.8 -05:11:56 6.4 0.79 77 PPM 195546 12:31:23.9 -06:10:14 7.9 0.47 77 PPM 195527 12:29:54.4 -05:45:00 9.3 0.19 78 4007_Euryalos 12:30:40.3 -05:43:53 16.2 77 Positions are for equinox of date
Star training set for 4007_Euryalos, (2026/07/26 06:31UT) Object RA Dec mag sep mel Spica 13:25:11.5 -11:09:41 1.0 14.90 63 4Gam Crv 12:15:48.1 -17:32:30 2.6 12.40 75 PPM 195577 12:31:38.7 -05:03:09 6.4 0.79 77 PPM 195546 12:30:01.7 -06:01:26 7.9 0.47 77 PPM 195527 12:28:32.2 -05:36:12 9.3 0.19 78 4007_Euryalos 12:29:18.2 -05:35:06 16.2 77 Positions are for J2000