RECON: TNO occultation with 98WY31

Event between 98WY31 and star GA1120:02595106 with event index number of 1238379

Geocentric closest approach at 2022/12/08 20:42:40 UTC

J2000 position of star is 07:00:58.3 +23:59:42
Equinox of date position of star is 07:02:18.4 +23:57:45
Stellar brightness G=15.2, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 20 degrees from the moon. Moon is 99% illuminated.
TNO apparent brightness V=23.2

TNO is 42.7 AU from the Sun and 41.8 AU from the Earth.
The TNO is moving 22.3 km/sec on the sky relative to the star, or, 2.6 arcsec/hr.
The 1-sigma error in the time of the event is 175 seconds.
The 1-sigma cross-track error in the shadow position is 1542 km.

The TNO has an absolute magnitude Hv=6.9
Diameter=259.4 km assuming a 5% albedo -- 11.4 sec chord
Diameter=105.9 km assuming a 30% albedo -- 4.7 sec chord
Dynamical classification is CLASSICAL
 
 
 
 
 
 
 
 

Star training set for 98WY31, (2022/12/08 20:46UT)
Object            RA         Dec     mag  sep  mel
Pollux         07:46:43.1 +27:58:08  1.1 10.74  29
Alhena         06:39:02.2 +16:22:40  1.9  9.35  18
42Ome Gem      07:03:48.5 +24:10:50  5.2  0.40  20
PPM 096887     07:02:16.8 +24:26:49  8.5  0.49  19
PPM 096907     07:02:53.3 +24:12:43  9.9  0.28  20
98WY31         07:02:22.0 +23:57:40 15.2        20
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, (2022/12/08 20:46UT)
Object            RA         Dec     mag  sep  mel
Pollux         07:45:17.9 +28:01:33  1.1 10.74  29
Alhena         06:37:42.8 +16:23:57  1.9  9.35  18
42Ome Gem      07:02:24.8 +24:12:55  5.2  0.40  20
PPM 096887     07:00:52.9 +24:28:51  8.5  0.49  19
PPM 096907     07:01:29.5 +24:14:46  9.9  0.28  20
98WY31         07:00:58.3 +23:59:42 15.2        20
Positions are for J2000

Event circumstances last updated at 2021/12/18 01:52:28 UT

Marc W. Buie, Southwest Research Institute

RECON