RECON: TNO occultation with 612203

Event between (612203) 00WT169 and star GA1120:02526567 with event index number of 2809233

Geocentric closest approach at 2028/01/20 20:29:27 UTC

J2000 position of star is 06:43:58.2 +22:44:44
Equinox of date position of star is 06:45:19.4 +22:43:17
Stellar brightness G=11.5, use SENSEUP=8 with the MallinCam and and exposure time of 125 milli-seconds with the QHY174 camera.
Star is 135 degrees from the moon. Moon is 29% illuminated.
TNO apparent brightness V=22.7

TNO is 45.2 AU from the Sun and 44.2 AU from the Earth.
The TNO is moving 24.1 km/sec on the sky relative to the star, or, 2.7 arcsec/hr.
The 1-sigma error in the time of the event is 763 seconds.
The 1-sigma cross-track error in the shadow position is 2066 km.

The TNO has an absolute magnitude Hv=6.1
Diameter=356.5 km assuming a 5% albedo -- 14.8 sec chord
Diameter=145.5 km assuming a 30% albedo -- 6.0 sec chord
Dynamical classification is CLASSICAL
 
 
 
 
 
 
 
 

Star training set for 612203, (2028/01/20 20:29UT)
Object            RA         Dec     mag  sep  mel
Pollux         07:47:02.0 +27:57:22  1.1 14.81 122
Alhena         06:39:19.9 +16:22:22  1.9  6.52 135
PPM 096308     06:40:46.5 +22:00:13  6.0  1.34 136
PPM 096508     06:47:52.4 +23:20:23  7.4  0.81 134
PPM 096467     06:46:06.2 +22:32:54 10.0  0.20 135
PPM 096450     06:45:33.5 +22:42:33 10.8  0.03 135
612203         06:45:39.9 +22:42:55 11.5       134
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 612203, (2028/01/20 20:29UT)
Object            RA         Dec     mag  sep  mel
Pollux         07:45:17.9 +28:01:33  1.1 14.81 122
Alhena         06:37:42.8 +16:23:56  1.9  6.52 135
PPM 096308     06:39:05.3 +22:01:51  6.0  1.34 136
PPM 096508     06:46:10.3 +23:22:18  7.4  0.81 134
PPM 096467     06:44:24.6 +22:34:44 10.0  0.20 135
PPM 096450     06:43:51.8 +22:44:22 10.8  0.03 135
612203         06:43:58.2 +22:44:44 11.5       135
Positions are for J2000

Event circumstances last updated at 2022/05/21 23:03:30 UT

Marc W. Buie, Southwest Research Institute

RECON