RECON: TNO occultation with 434390

Event between (434390) 05CH81 and star TYC20849-00063-1 with event index number of 73985

Geocentric closest approach at 2017/03/13 17:48:16 UTC

J2000 position of star is 10:44:21.6 +11:20:08
Equinox of date position of star is 10:45:12.8 +11:15:01
Stellar brightness V=9.9
Star is 28 degrees from the moon. Moon is 99% illuminated.
TNO apparent brightness V=24.0

TNO is 38.2 AU from the Sun and 37.2 AU from the Earth.
The TNO is moving 23.6 km/sec on the sky relative to the star, or, 3.1 arcsec/hr.
The 1-sigma error in the time of the event is 157 seconds.
The 1-sigma cross-track error in the shadow position is 2222 km.

The TNO has an absolute magnitude Hv=8.2
Diameter=138.0 km assuming a 5% albedo -- 5.9 sec chord
Diameter=56.4 km assuming a 30% albedo -- 2.4 sec chord
Dynamical classification is SCATNEAR
 
 
 
 
 
 
 
 

Star training set for 434390, (2017/03/13 17:48UT)
Object            RA         Dec     mag  sep  mel
Regulus        10:09:17.2 +11:52:57  1.3  8.83  37
53 Leo         10:50:09.6 +10:27:14  5.3  1.44  27
PPM 127689     10:47:30.9 +11:05:33  8.5  0.57  28
PPM 127662     10:45:15.9 +11:14:42  9.7  0.00  28
434390         10:45:15.9 +11:14:42  9.9        28
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 2016/03/20 17:19:40 UT

Marc W. Buie, Southwest Research Institute

RECON