RECON: TNO occultation with 531142

Event between (531142) 12FL84 and star GA0760:05098538 with event index number of 1601027

Geocentric closest approach at 2021/05/31 14:51:44 UTC

J2000 position of star is 14:57:10.6 -13:23:42
Equinox of date position of star is 14:58:20.0 -13:28:44
Stellar brightness G=15.3, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 94 degrees from the moon. Moon is 68% illuminated.
TNO apparent brightness V=22.9

TNO is 40.8 AU from the Sun and 39.9 AU from the Earth.
The TNO is moving 21.9 km/sec on the sky relative to the star, or, 2.7 arcsec/hr.
The 1-sigma error in the time of the event is 114 seconds.
The 1-sigma cross-track error in the shadow position is 2381 km.

The TNO has an absolute magnitude Hv=6.8
Diameter=263.0 km assuming a 5% albedo -- 12.0 sec chord
Diameter=107.4 km assuming a 30% albedo -- 4.9 sec chord
Dynamical classification is SCATNEAR
 
 
 
 
 
 
 
 

Star training set for 531142, (2021/05/31 14:52UT)
Object            RA         Dec     mag  sep  mel
Spica          13:26:19.5 -11:16:21  1.0 22.57 116
27Bet Lib      15:18:09.7 -09:27:38  2.6  6.30  91
13Xi 1Lib      14:55:32.8 -11:59:04  5.9  1.64  96
PPM 229495     14:56:57.8 -13:17:30  8.5  0.39  95
PPM 229549     14:59:00.1 -13:27:59  9.9  0.16  94
531142         14:58:21.2 -13:28:49 15.3        94
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 531142, (2021/05/31 14:52UT)
Object            RA         Dec     mag  sep  mel
Spica          13:25:11.5 -11:09:41  1.0 22.57 116
27Bet Lib      15:17:00.3 -09:22:59  2.6  6.30  91
13Xi 1Lib      14:54:22.8 -11:53:54  5.9  1.64  96
PPM 229495     14:55:47.3 -13:12:21  8.5  0.39  95
PPM 229549     14:57:49.4 -13:22:53  9.9  0.16  94
531142         14:57:10.6 -13:23:42 15.3        94
Positions are for J2000

Event circumstances last updated at 2021/01/21 21:30:47 UT

Marc W. Buie, Southwest Research Institute

RECON