RECON: TNO occultation with 471172

Event between (471172) 10JC80 and star GA0640:15266139 with event index number of 2239825

Geocentric closest approach at 2026/10/02 12:03:52 UTC

J2000 position of star is 17:25:40.5 -24:54:01
Equinox of date position of star is 17:27:10.8 -24:55:12
Stellar brightness G=16.4, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 176 degrees from the moon. Moon is 62% illuminated.
Apparent brightness V=21.3

Object is 31.5 AU from the Sun and 31.8 AU from the Earth.
Apparent velocity is 15.4 km/sec on the sky relative to the star, or, 2.4 arcsec/hr.
The 1-sigma error in the time of the event is 270 seconds.
The 1-sigma cross-track error in the shadow position is 1350 km.

The object has an absolute magnitude Hv=6.1
Diameter=358.1 km assuming a 5% albedo -- 23.4 sec chord
Diameter=146.2 km assuming a 30% albedo -- 9.6 sec chord
Dynamical classification is 5:2EEE
 
 
 
 
 
 
 
 

Star training set for 471172, (2026/10/02 12:04UT)
Object            RA         Dec     mag  sep  mel
Antares        16:31:03.1 -26:29:20  0.9 12.76 164
35Eta Oph      17:11:54.9 -15:45:22  2.6  9.85 166
PPM 266836     17:26:44.5 -24:15:57  6.4  0.67 175
PPM 266839     17:26:49.2 -24:37:38  8.5  0.32 175
PPM 266826     17:26:20.9 -24:49:55  9.8  0.24 175
471172         17:27:19.2 -24:55:19 16.4       176
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 471172, (2026/10/02 12:04UT)
Object            RA         Dec     mag  sep  mel
Antares        16:29:24.4 -26:25:56  0.9 12.76 164
35Eta Oph      17:10:22.7 -15:43:29  2.6  9.85 166
PPM 266836     17:25:06.3 -24:14:37  6.4  0.67 175
PPM 266839     17:25:10.8 -24:36:19  8.5  0.32 175
PPM 266826     17:24:42.3 -24:48:35  9.8  0.24 175
471172         17:25:40.5 -24:54:01 16.4       176
Positions are for J2000

Event circumstances last updated at 2024/06/20 21:25:14 UT

Marc W. Buie, Southwest Research Institute

RECON