Occultation event with (5209) Oloosson, event index number 3906
Regions able to see the event: SAmericaN
Geocentric closest approach at 2026/07/29 23:28:27 UTC
J2000 position of star is 13:10:57.4 -16:29:38
Equinox of date position of star is 13:12:22.4 -16:38:05
Star is 108 degrees from the moon. Moon is 100% illuminated.
Stellar brightness G=16.3, apparent brightess of occulting body is G=16.2
Use an exposure time of 0.75 seconds with the standard RECON-QHY system.
SNR of 3.0 per integration for unocculted signal
Expected flux drop is 48% with SNR of 1.4 for the occulted depth (per occulted point)
Apparent velocity is 19.8 km/sec on the sky relative to the star, or, 17.6 arcsec/hr.
Position angle of asteroid motion is 103.5 degrees
The recommended exposure time corresponds to 14.8 km per image.
The 1-sigma error in the time of the event is 1.1 seconds.
The 1-sigma cross-track error in the shadow position is 25.4 km.
The sky-plane scale is 4047.8 km/arcsec.
Diameter estimates:
52.0 km assuming a 5% albedo, maximum of 2.6 sec for a central chord
21.2 km assuming a 30% albedo, maximum of 1.1 sec for a central chord
Cross-track diameter of 48.2 km used for deployment plan.
Star training set for 5209_Oloosson, (2026/07/29 23:28UT) Object RA Dec mag sep mel Spica 13:26:35.8 -11:17:57 1.0 6.35 107 53 Vir 13:13:28.7 -16:20:28 4.8 0.40 108 PPM 226881 13:11:07.2 -16:39:22 7.0 0.30 108 PPM 226930 13:13:18.0 -16:39:15 8.9 0.22 108 5209_Oloosson 13:12:22.4 -16:38:05 16.2 108 Positions are for equinox of date
Star training set for 5209_Oloosson, (2026/07/29 23:28UT) Object RA Dec mag sep mel Spica 13:25:11.5 -11:09:41 1.0 6.35 107 53 Vir 13:12:03.7 -16:12:02 4.8 0.40 108 PPM 226881 13:09:42.3 -16:30:55 7.0 0.30 108 PPM 226930 13:11:52.9 -16:30:49 8.9 0.22 108 5209_Oloosson 13:10:57.4 -16:29:38 16.2 108 Positions are for J2000