RECON: TNO occultation with 500839

Event between (500839) 13GW137 and star UC4-379-067088 with event index number of 220695

Geocentric closest approach at 2018/06/14 23:33:44 UTC

J2000 position of star is 14:30:36.5 -14:19:28
Equinox of date position of star is 14:31:35.3 -14:24:12
Stellar brightness R=16.0, use SENSEUP=128
Star is 120 degrees from the moon. Moon is 2% illuminated.
TNO apparent brightness V=23.8

TNO is 40.3 AU from the Sun and 39.5 AU from the Earth.
The TNO is moving 16.5 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 266 seconds.
The 1-sigma cross-track error in the shadow position is 2330 km.

The TNO has an absolute magnitude Hv=7.7
Diameter=173.8 km assuming a 5% albedo -- 10.5 sec chord
Diameter=70.9 km assuming a 30% albedo -- 4.3 sec chord
Dynamical classification is CLASSICAL
 
 
 
 
 
 
 
 

Star training set for 500839, (2018/06/14 23:34UT)
Object            RA         Dec     mag  sep  mel
Spica          13:26:10.1 -11:15:25  1.0 16.26 104
27Bet Lib      15:18:00.2 -09:27:00  2.6 12.38 129
PPM 229046     14:37:58.9 -12:22:59  6.2  2.55 121
PPM 228892     14:31:14.7 -15:19:46  7.5  0.93 120
PPM 228891     14:31:09.0 -14:21:27  9.3  0.12 120
500839         14:31:37.1 -14:24:21 16.0       120
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 500839, (2018/06/14 23:34UT)
Object            RA         Dec     mag  sep  mel
Spica          13:25:11.5 -11:09:41  1.0 16.26 104
27Bet Lib      15:17:00.3 -09:22:59  2.6 12.38 129
PPM 229046     14:36:58.7 -12:18:13  6.2  2.55 121
PPM 228892     14:30:13.9 -15:14:53  7.5  0.93 120
PPM 228891     14:30:08.4 -14:16:34  9.3  0.12 120
500839         14:30:36.5 -14:19:28 16.0       120
Positions are for J2000

Event circumstances last updated at 2017/12/04 18:44:58 UT

Marc W. Buie, Southwest Research Institute

RECON