Occultation event with (15502) 99NV27, event index number 1299
Regions able to see the event: SAmericaN,SAfrica
Geocentric closest approach at 2025/09/21 02:28:59 UTC
J2000 position of star is 01:38:54.6 +31:28:51
Equinox of date position of star is 01:40:22.6 +31:36:38
Star is 132 degrees from the moon. Moon is 1% illuminated.
Stellar brightness G=15.3, apparent brightess of occulting body is G=15.2
Use an exposure time of 1.05 seconds with the standard RECON-QHY system.
SNR of 8.3 per integration for unocculted signal
Expected flux drop is 48% with SNR of 4.0 for the occulted depth (per occulted point)
Apparent velocity is 12.6 km/sec on the sky relative to the star, or, 14.4 arcsec/hr.
Position angle of asteroid motion is 96.1 degrees
The recommended exposure time corresponds to 13.2 km per image.
The 1-sigma error in the time of the event is 0.6 seconds.
The 1-sigma cross-track error in the shadow position is 24.9 km.
The sky-plane scale is 3138.7 km/arcsec.
Diameter estimates:
57.5 km assuming a 5% albedo, aximum of 4.6 sec for a central chord
23.5 km assuming a 30% albedo, maximum of 1.9 sec for a central chord
Cross-track diameter of 53.1 km used for deployment plan.
Star training set for 15502_99NV27, (2025/09/21 02:29UT) Object RA Dec mag sep mel Aldebaran 04:37:24.0 +16:33:32 0.8 42.77 100 Hamal 02:08:37.8 +23:34:58 2.0 10.17 132 PPM 066632 01:50:10.5 +32:49:10 6.2 2.40 130 PPM 066479 01:40:19.9 +31:46:46 8.4 0.17 132 15502_99NV27 01:40:22.6 +31:36:38 15.2 132 Positions are for equinox of date
Star training set for 15502_99NV27, (2025/09/21 02:29UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 42.77 100 Hamal 02:07:10.8 +23:27:41 2.0 10.17 132 PPM 066632 01:48:41.2 +32:41:33 6.2 2.40 130 PPM 066479 01:38:51.8 +31:38:59 8.4 0.17 132 15502_99NV27 01:38:54.6 +31:28:51 15.2 132 Positions are for J2000