Occultation event with (15502) 99NV27, event index number 4068
Regions able to see the event: SAmericaN
Geocentric closest approach at 2026/08/21 08:19:58 UTC
J2000 position of star is 04:17:42.3 +37:18:15
Equinox of date position of star is 04:19:28.8 +37:22:04
Star is 169 degrees from the moon. Moon is 62% illuminated.
Stellar brightness G=16.5, apparent brightess of occulting body is G=15.7
Use an exposure time of 1.05 seconds with the standard RECON-QHY system.
SNR of 3.1 per integration for unocculted signal
Expected flux drop is 33% with SNR of 1.0 for the occulted depth (per occulted point)
Apparent velocity is 19.1 km/sec on the sky relative to the star, or, 18.4 arcsec/hr.
Position angle of asteroid motion is 61.8 degrees
The recommended exposure time corresponds to 20.1 km per image.
The 1-sigma error in the time of the event is 0.7 seconds.
The 1-sigma cross-track error in the shadow position is 23.8 km.
The sky-plane scale is 3755.8 km/arcsec.
Diameter estimates:
57.5 km assuming a 5% albedo, maximum of 3.0 sec for a central chord
23.5 km assuming a 30% albedo, maximum of 1.2 sec for a central chord
Cross-track diameter of 53.1 km used for deployment plan.
Star training set for 15502_99NV27, (2026/08/21 08:20UT) Object RA Dec mag sep mel Aldebaran 04:37:27.1 +16:33:38 0.8 21.18 169 44Zet Per 03:55:48.8 +31:57:38 2.8 7.27 169 50 Per 04:10:23.6 +38:06:25 5.5 1.94 168 PPM 069300 04:20:08.5 +37:38:25 8.4 0.30 169 PPM 069285 04:18:52.9 +37:20:45 10.4 0.12 169 15502_99NV27 04:19:28.8 +37:22:04 15.7 169 Positions are for equinox of date
Star training set for 15502_99NV27, (2026/08/21 08:20UT) Object RA Dec mag sep mel Aldebaran 04:35:55.4 +16:30:29 0.8 21.18 169 44Zet Per 03:54:07.9 +31:53:01 2.8 7.27 169 50 Per 04:08:37.0 +38:02:18 5.5 1.94 168 PPM 069300 04:18:21.7 +37:34:37 8.4 0.30 169 PPM 069285 04:17:06.5 +37:16:55 10.4 0.12 169 15502_99NV27 04:17:42.3 +37:18:15 15.7 169 Positions are for J2000