RECON: TNO occultation with 04HX78

Event between 04HX78 and star UC4-377-079351 with event index number of 55591

Geocentric closest approach at 2017/06/17 19:35:13 UTC

J2000 position of star is 17:08:21.8 -14:38:58
Equinox of date position of star is 17:09:17.2 -14:40:10
Stellar brightness R=13.2
Star is 104 degrees from the moon. Moon is 47% illuminated.
TNO apparent brightness V=23.3

TNO is 33.5 AU from the Sun and 32.5 AU from the Earth.
The TNO is moving 23.6 km/sec on the sky relative to the star, or, 3.6 arcsec/hr.
The 1-sigma error in the time of the event is 392 seconds.
The 1-sigma cross-track error in the shadow position is 1693 km.

The TNO has an absolute magnitude Hv=8.1
Diameter=143.9 km assuming a 5% albedo -- 6.1 sec chord
Diameter=58.7 km assuming a 30% albedo -- 2.5 sec chord
Dynamical classification is 3:2E
 
 
 
 
 
 
 
 

Star training set for 04HX78, (2017/06/17 19:35UT)
Object            RA         Dec     mag  sep  mel
Antares        16:30:28.8 -26:28:09  0.9 14.88 111
35Eta Oph      17:11:22.8 -15:44:43  2.6  1.18 103
PPM 232829     17:16:19.9 -14:36:10  5.9  1.69 102
PPM 232610     17:07:28.8 -13:57:27  7.6  0.85 104
PPM 232640     17:08:49.7 -14:42:51  8.7  0.14 104
04HX78         17:09:21.5 -14:40:16 13.2       104
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.

Event circumstances last updated at 2016/03/14 18:00:27 UT

Marc W. Buie, Southwest Research Institute

RECON