RECON: TNO occultation with 552678

Event between (552678) 10JG210 and star GA0820:11566756 with event index number of 2223855

Geocentric closest approach at 2026/07/12 18:26:42 UTC

J2000 position of star is 18:43:06.9 -07:57:49
Equinox of date position of star is 18:44:21.4 -07:56:22
Stellar brightness G=15.8, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 156 degrees from the moon. Moon is 4% illuminated.
TNO apparent brightness V=21.0

TNO is 17.6 AU from the Sun and 16.6 AU from the Earth.
The TNO is moving 21.6 km/sec on the sky relative to the star, or, 6.5 arcsec/hr.
The 1-sigma error in the time of the event is 111 seconds.
The 1-sigma cross-track error in the shadow position is 1226 km.

The TNO has an absolute magnitude Hv=8.5
Diameter=114.3 km assuming a 5% albedo -- 5.5 sec chord
Diameter=46.7 km assuming a 30% albedo -- 2.2 sec chord
Dynamical classification is CENTAURR
 
 
 
 
 
 
 
 

Star training set for 552678, (2026/07/12 18:25UT)
Object            RA         Dec     mag  sep  mel
Antares        16:31:02.3 -26:29:19  0.9 36.70 163
Nunki          18:56:54.5 -26:15:41  2.0 18.56 165
Eps Sct        18:44:57.9 -08:14:49  4.9  0.33 156
PPM 202078     18:45:09.8 -07:42:10  8.5  0.28 156
PPM 202062     18:44:33.8 -07:41:20  8.7  0.25 156
552678         18:44:33.4 -07:56:08 15.8       156
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 552678, (2026/07/12 18:25UT)
Object            RA         Dec     mag  sep  mel
Antares        16:29:24.4 -26:25:56  0.9 36.70 163
Nunki          18:55:15.9 -26:17:49  2.0 18.56 165
Eps Sct        18:43:31.3 -08:16:31  4.9  0.33 156
PPM 202078     18:43:43.5 -07:43:52  8.5  0.28 156
PPM 202062     18:43:07.5 -07:43:02  8.7  0.25 156
552678         18:43:06.9 -07:57:49 15.8       156
Positions are for J2000

Event circumstances last updated at 2022/11/04 04:00:28 UT

Marc W. Buie, Southwest Research Institute

RECON