RECON: TNO occultation with 98WY31

Event between 98WY31 and star UC4-572-031066 with event index number of 178311

Geocentric closest approach at 2019/01/10 21:48:53 UTC

J2000 position of star is 06:34:46.3 +24:20:53
Equinox of date position of star is 06:35:52.1 +24:19:58
Stellar brightness R=10.8, use SENSEUP=4
Star is 115 degrees from the moon. Moon is 20% illuminated.
TNO apparent brightness V=23.1

TNO is 43.1 AU from the Sun and 42.1 AU from the Earth.
The TNO is moving 25.0 km/sec on the sky relative to the star, or, 2.9 arcsec/hr.
The 1-sigma error in the time of the event is 615 seconds.
The 1-sigma cross-track error in the shadow position is 3356 km.

The TNO has an absolute magnitude Hv=6.8
Diameter=257.0 km assuming a 5% albedo -- 10.3 sec chord
Diameter=104.9 km assuming a 30% albedo -- 4.2 sec chord
Dynamical classification is CLASSICAL
 
 
 
 
 
 
 
 

Star training set for 98WY31, (2019/01/10 21:49UT)
Object            RA         Dec     mag  sep  mel
Pollux         07:46:28.7 +27:58:43  1.1 16.23 131
Alhena         06:38:48.7 +16:22:53  1.9  7.98 116
PPM 096264     06:38:37.2 +24:34:24  6.5  0.66 116
PPM 096208     06:36:04.3 +24:16:50  9.9  0.06 115
98WY31         06:35:56.1 +24:19:54 10.8       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 98WY31, (2019/01/10 21:49UT)
Object            RA         Dec     mag  sep  mel
Pollux         07:45:18.1 +28:01:33  1.1 16.23 131
Alhena         06:37:42.8 +16:23:57  1.9  7.98 116
PPM 096264     06:37:27.2 +24:35:27  6.5  0.66 116
PPM 096208     06:34:54.5 +24:17:49  9.9  0.06 115
98WY31         06:34:46.3 +24:20:53 10.8       115
Positions are for J2000

Event circumstances last updated at 2017/12/05 19:10:32 UT

Marc W. Buie, Southwest Research Institute

RECON