RECON: TNO occultation with 437871

Event between (437871) 01FN185 and star UC4-410-059964 with event index number of 119905

Geocentric closest approach at 2018/05/19 02:23:52 UTC

J2000 position of star is 14:48:34.0 -08:09:59
Equinox of date position of star is 14:49:29.6 -08:14:17
Stellar brightness R=14.1, use SENSEUP=64
Star is 115 degrees from the moon. Moon is 18% illuminated.
TNO apparent brightness V=23.2

TNO is 39.5 AU from the Sun and 38.5 AU from the Earth.
The TNO is moving 23.9 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 286 seconds.
The 1-sigma cross-track error in the shadow position is 1975 km.

The TNO has an absolute magnitude Hv=7.2
Diameter=218.8 km assuming a 5% albedo -- 9.2 sec chord
Diameter=89.3 km assuming a 30% albedo -- 3.7 sec chord
Dynamical classification is SCATEXTD
 
 
 
 
 
 
 
 

Star training set for 437871, (2018/05/19 02:24UT)
Object            RA         Dec     mag  sep  mel
Spica          13:26:09.8 -11:15:24  1.0 20.76  96
27Bet Lib      15:17:59.9 -09:26:59  2.6  7.13 122
107Mu Vir      14:44:01.9 -05:44:14  3.9  2.85 113
PPM 197945     14:50:24.4 -08:34:48  7.4  0.40 115
PPM 197940     14:50:16.1 -08:27:01  9.3  0.27 115
437871         14:49:32.8 -08:14:32 14.1       115
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 437871, (2018/05/19 02:24UT)
Object            RA         Dec     mag  sep  mel
Spica          13:25:11.5 -11:09:41  1.0 20.76  96
27Bet Lib      15:17:00.3 -09:22:59  2.6  7.13 122
107Mu Vir      14:43:03.8 -05:39:35  3.9  2.85 113
PPM 197945     14:49:25.4 -08:30:16  7.4  0.40 115
PPM 197940     14:49:17.1 -08:22:29  9.3  0.27 115
437871         14:48:34.0 -08:09:59 14.1       115
Positions are for J2000

Event circumstances last updated at 2017/05/18 18:03:42 UT

Marc W. Buie, Southwest Research Institute

RECON