Occultation event with (21601) 98XO89, event index number 3821
Regions able to see the event: Japan
Geocentric closest approach at 2026/07/01 11:09:41 UTC
J2000 position of star is 13:15:16.6 -24:35:47
Equinox of date position of star is 13:16:43.4 -24:44:09
Star is 88 degrees from the moon. Moon is 98% illuminated.
Stellar brightness G=16.5, apparent brightess of occulting body is G=15.6
Use an exposure time of 1.30 seconds with the standard RECON-QHY system.
SNR of 3.6 per integration for unocculted signal
Expected flux drop is 30% with SNR of 1.1 for the occulted depth (per occulted point)
Apparent velocity is 10.5 km/sec on the sky relative to the star, or, 10.6 arcsec/hr.
Position angle of asteroid motion is 43.8 degrees
The recommended exposure time corresponds to 13.6 km per image.
The 1-sigma error in the time of the event is 1.9 seconds.
The 1-sigma cross-track error in the shadow position is 29.6 km.
The sky-plane scale is 3549.3 km/arcsec.
Diameter estimates:
60.0 km assuming a 5% albedo, maximum of 5.7 sec for a central chord
24.5 km assuming a 30% albedo, maximum of 2.3 sec for a central chord
Cross-track diameter of 54.9 km used for deployment plan.
Star training set for 21601_98XO89, (2026/07/01 11:10UT) Object RA Dec mag sep mel Spica 13:26:35.6 -11:17:56 1.0 13.64 92 9Bet Crv 12:35:47.1 -23:32:35 2.6 9.41 97 46Gam Hya 13:20:22.1 -23:18:38 3.0 1.65 88 PPM 261387 13:15:54.1 -24:25:26 7.1 0.36 89 PPM 261398 13:16:28.4 -25:01:43 9.6 0.30 88 21601_98XO89 13:16:43.4 -24:44:09 15.6 88 Positions are for equinox of date
Star training set for 21601_98XO89, (2026/07/01 11:10UT) Object RA Dec mag sep mel Spica 13:25:11.5 -11:09:41 1.0 13.64 92 9Bet Crv 12:34:23.2 -23:23:50 2.6 9.41 97 46Gam Hya 13:18:55.4 -23:10:19 3.0 1.65 88 PPM 261387 13:14:27.4 -24:17:03 7.1 0.36 89 PPM 261398 13:15:01.6 -24:53:21 9.6 0.30 88 21601_98XO89 13:15:16.6 -24:35:47 15.6 88 Positions are for J2000