RECON: TNO occultation with 505477

Event between (505477) 13UM15 and star GA1000:00181987 with event index number of 2397373

Geocentric closest approach at 2026/09/15 16:12:48 UTC

J2000 position of star is 02:04:20.6 +10:39:41
Equinox of date position of star is 02:05:39.0 +10:46:40
Stellar brightness G=15.4, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 164 degrees from the moon. Moon is 21% illuminated.
Apparent brightness V=23.6

Object is 45.3 AU from the Sun and 44.5 AU from the Earth.
Apparent velocity is 18.5 km/sec on the sky relative to the star, or, 2.1 arcsec/hr.
The 1-sigma error in the time of the event is 370 seconds.
The 1-sigma cross-track error in the shadow position is 4290 km.

The object has an absolute magnitude Hv=7.0
Diameter=251.2 km assuming a 5% albedo -- 12.7 sec chord
Diameter=102.6 km assuming a 30% albedo -- 5.2 sec chord
Dynamical classification is 11:6EEEEE
 
 
 
 
 
 
 
 

Star training set for 505477, (2026/09/15 16:13UT)
Object            RA         Dec     mag  sep  mel
Aldebaran      04:37:27.4 +16:33:40  0.8 37.24 155
6Bet Ari       01:56:07.2 +20:56:15  2.6 10.41 166
PPM 117850     02:00:51.9 +12:25:24  6.1  2.03 164
PPM 117903     02:04:23.3 +11:08:46  7.5  0.49 164
PPM 117926     02:06:16.6 +10:55:55  9.3  0.19 164
505477         02:05:46.2 +10:47:18 15.4       164
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 505477, (2026/09/15 16:13UT)
Object            RA         Dec     mag  sep  mel
Aldebaran      04:35:55.3 +16:30:29  0.8 37.24 155
6Bet Ari       01:54:38.5 +20:48:26  2.6 10.41 166
PPM 117850     01:59:25.9 +12:17:40  6.1  2.03 164
PPM 117903     02:02:57.6 +11:01:07  7.5  0.49 164
PPM 117926     02:04:51.0 +10:48:18  9.3  0.19 164
505477         02:04:20.6 +10:39:41 15.4       164
Positions are for J2000

Event circumstances last updated at 2024/06/19 21:32:47 UT

Marc W. Buie, Southwest Research Institute

RECON