RECON: TNO occultation with 523790

Event between (523790) 15HP9 and star GA0680:23364715 with event index number of 2605115

Geocentric closest approach at 2026/08/04 08:41:17 UTC

J2000 position of star is 18:14:24.5 -21:06:17
Equinox of date position of star is 18:15:52.3 -21:05:45
Stellar brightness G=14.2, use SENSEUP=64 with the MallinCam and and exposure time of 1 seconds with the QHY174 camera.
Star is 106 degrees from the moon. Moon is 69% illuminated.
Apparent brightness V=23.1

Object is 17.6 AU from the Sun and 16.8 AU from the Earth.
Apparent velocity is 15.9 km/sec on the sky relative to the star, or, 4.7 arcsec/hr.
The 1-sigma error in the time of the event is 373 seconds.
The 1-sigma cross-track error in the shadow position is 1279 km.

The object has an absolute magnitude Hv=10.5
Diameter=50.1 km assuming a 5% albedo -- 3.0 sec chord
Diameter=20.5 km assuming a 30% albedo -- 1.2 sec chord
Dynamical classification is CENTAURR
 
 
 
 
 
 
 
 

Star training set for 523790, (2026/08/04 08:41UT)
Object            RA         Dec     mag  sep  mel
Antares        16:31:02.5 -26:29:19  0.9 24.56 130
Nunki          18:56:54.7 -26:15:40  2.0 10.69  98
13Mu Sgr       18:15:21.2 -21:02:58  3.9  0.16 106
PPM 268119     18:16:37.5 -20:51:40  8.3  0.28 106
13Mu Sgr       18:15:21.2 -21:02:58  3.9  0.16 106
523790         18:15:59.9 -21:05:42 14.2       106
Positions are for equinox of date

Azimuth is measured in degrees eastward from north. North is at an azimuth of 0, due East is at an azimuth of 90 degrees, due South is 180, and due West is 270.

Do not use the listing below for the RECON CPC 1100 telescopes. This is provided for other non-team facilities.

Star training set for 523790, (2026/08/04 08:41UT)
Object            RA         Dec     mag  sep  mel
Antares        16:29:24.4 -26:25:56  0.9 24.56 130
Nunki          18:55:15.9 -26:17:49  2.0 10.69  98
13Mu Sgr       18:13:45.8 -21:03:32  3.9  0.16 106
PPM 268119     18:15:02.2 -20:52:16  8.3  0.28 106
13Mu Sgr       18:13:45.8 -21:03:32  3.9  0.16 106
523790         18:14:24.5 -21:06:17 14.2       106
Positions are for J2000

Event circumstances last updated at 2024/06/19 21:32:20 UT

Marc W. Buie, Southwest Research Institute

RECON