RECON: TNO occultation with 278361

Event between (278361) 07JJ43 and star UC4-319-090617 with event index number of 203906

Geocentric closest approach at 2019/07/25 17:50:50 UTC

J2000 position of star is 16:45:54.9 -26:13:41
Equinox of date position of star is 16:47:00.0 -26:15:32
Stellar brightness R=16.1, use SENSEUP=128
Star is 146 degrees from the moon. Moon is 43% illuminated.
TNO apparent brightness V=20.7

TNO is 40.9 AU from the Sun and 40.3 AU from the Earth.
The TNO is moving 14.5 km/sec on the sky relative to the star, or, 1.8 arcsec/hr.
The 1-sigma error in the time of the event is 196 seconds.
The 1-sigma cross-track error in the shadow position is 1815 km.

The TNO has an absolute magnitude Hv=4.5
Diameter=758.6 km assuming a 5% albedo -- 52.3 sec chord
Diameter=309.7 km assuming a 30% albedo -- 21.3 sec chord
Dynamical classification is SCATNEAR
 
 
 
 
 
 
 
 

Star training set for 278361, (2019/07/25 17:51UT)
Object            RA         Dec     mag  sep  mel
Antares        16:30:36.6 -26:28:26  0.9  3.70 149
23Tau Sco      16:37:06.2 -28:15:18  2.8  2.99 147
PPM 265803     16:42:50.8 -27:50:46  6.5  1.85 146
PPM 265881     16:45:34.2 -26:21:36  8.5  0.36 146
PPM 265938     16:47:43.2 -26:21:20  9.2  0.16 146
278361         16:47:07.3 -26:15:45 16.1       146
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 278361, (2019/07/25 17:51UT)
Object            RA         Dec     mag  sep  mel
Antares        16:29:24.4 -26:25:56  0.9  3.70 149
23Tau Sco      16:35:53.0 -28:12:58  2.8  2.99 147
PPM 265803     16:41:37.6 -27:48:35  6.5  1.85 146
PPM 265881     16:44:21.8 -26:19:30  8.5  0.36 146
PPM 265938     16:46:30.7 -26:19:17  9.2  0.16 146
278361         16:45:54.9 -26:13:41 16.1       146
Positions are for J2000

Event circumstances last updated at 2017/08/05 16:41:04 UT

Marc W. Buie, Southwest Research Institute

RECON