Occultation event with (24313) 99YR27, event index number 3577
Regions able to see the event: SAmericaN
Geocentric closest approach at 2026/04/05 06:51:32 UTC
J2000 position of star is 11:32:29.5 +19:14:47
Equinox of date position of star is 11:33:51.6 +19:06:04
Star is 68 degrees from the moon. Moon is 90% illuminated.
Stellar brightness G=13.6, apparent brightess of occulting body is G=16.1
Use an exposure time of 0.18 seconds with the standard RECON-QHY system.
SNR of 9.8 per integration for unocculted signal
Expected flux drop is 91% with SNR of 9.0 for the occulted depth (per occulted point)
Apparent velocity is 15.5 km/sec on the sky relative to the star, or, 16.4 arcsec/hr.
Position angle of asteroid motion is 90.7 degrees
The recommended exposure time corresponds to 2.8 km per image.
The 1-sigma error in the time of the event is 1.5 seconds.
The 1-sigma cross-track error in the shadow position is 30.7 km.
The sky-plane scale is 3415.1 km/arcsec.
Diameter estimates:
41.9 km assuming a 5% albedo, maximum of 2.7 sec for a central chord
17.1 km assuming a 30% albedo, maximum of 1.1 sec for a central chord
Cross-track diameter of 34.6 km used for deployment plan.
Star training set for 24313_99YR27, (2026/04/05 06:52UT) Object RA Dec mag sep mel Regulus 10:09:46.1 +11:50:16 1.3 21.50 82 68Del Leo 11:15:30.1 +20:22:46 2.6 4.51 72 86 Leo 11:31:51.0 +18:15:53 6.3 0.96 68 PPM 128342 11:34:34.7 +18:40:34 8.2 0.46 68 PPM 128349 11:35:07.1 +19:25:03 9.4 0.43 68 PPM 128344 11:34:40.4 +19:02:05 10.1 0.20 68 24313_99YR27 11:33:51.6 +19:06:04 16.1 68 Positions are for equinox of date
Star training set for 24313_99YR27, (2026/04/05 06:52UT) Object RA Dec mag sep mel Regulus 10:08:21.9 +11:58:02 1.3 21.50 82 68Del Leo 11:14:06.8 +20:31:22 2.6 4.51 72 86 Leo 11:30:28.8 +18:24:35 6.3 0.96 68 PPM 128342 11:33:12.6 +18:49:17 8.2 0.46 68 PPM 128349 11:33:45.0 +19:33:46 9.4 0.43 68 PPM 128344 11:33:18.3 +19:10:48 10.1 0.20 68 24313_99YR27 11:32:29.5 +19:14:47 16.1 68 Positions are for J2000