Occultation event with (5209) Oloosson, event index number 3679
Regions able to see the event: SAmericaN
Geocentric closest approach at 2026/04/23 22:47:47 UTC
J2000 position of star is 13:13:26.0 -18:26:49
Equinox of date position of star is 13:14:50.6 -18:35:09
Star is 83 degrees from the moon. Moon is 48% illuminated.
Stellar brightness G=14.9, apparent brightess of occulting body is G=15.3
Use an exposure time of 0.70 seconds with the standard RECON-QHY system.
SNR of 8.8 per integration for unocculted signal
Expected flux drop is 59% with SNR of 5.2 for the occulted depth (per occulted point)
Apparent velocity is 16.7 km/sec on the sky relative to the star, or, 18.8 arcsec/hr.
Position angle of asteroid motion is 111.9 degrees
The recommended exposure time corresponds to 11.7 km per image.
The 1-sigma error in the time of the event is 1.6 seconds.
The 1-sigma cross-track error in the shadow position is 22.7 km.
The sky-plane scale is 3208.8 km/arcsec.
Diameter estimates:
52.0 km assuming a 5% albedo, maximum of 3.1 sec for a central chord
21.2 km assuming a 30% albedo, maximum of 1.3 sec for a central chord
Cross-track diameter of 48.2 km used for deployment plan.
Star training set for 5209_Oloosson, (2026/04/23 22:48UT) Object RA Dec mag sep mel Spica 13:26:35.0 -11:17:52 1.0 7.82 82 54 Vir 13:14:51.7 -18:57:52 6.1 0.38 83 PPM 226955 13:14:38.1 -18:35:43 9.5 0.05 83 5209_Oloosson 13:14:50.6 -18:35:09 15.3 83 Positions are for equinox of date
Star training set for 5209_Oloosson, (2026/04/23 22:48UT) Object RA Dec mag sep mel Spica 13:25:11.5 -11:09:41 1.0 7.82 82 54 Vir 13:13:26.9 -18:49:32 6.1 0.38 83 PPM 226955 13:13:13.4 -18:27:23 9.5 0.05 83 5209_Oloosson 13:13:26.0 -18:26:49 15.3 83 Positions are for J2000