RECON: TNO occultation with 55638

Event between (55638) 02VE95 and star GA0960:02346092 with event index number of 2249825

Geocentric closest approach at 2023/12/15 14:38:13 UTC

J2000 position of star is 06:54:33.8 +06:02:59
Equinox of date position of star is 06:55:50.7 +06:01:05
Stellar brightness G=16.7, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 154 degrees from the moon. Moon is 9% illuminated.
Apparent brightness V=20.6

Object is 31.1 AU from the Sun and 30.3 AU from the Earth.
Apparent velocity is 22.8 km/sec on the sky relative to the star, or, 3.7 arcsec/hr.
The 1-sigma error in the time of the event is 110 seconds.
The 1-sigma cross-track error in the shadow position is 1132 km.

The object has an absolute magnitude Hv=5.6
Diameter=524.8 km assuming a 5% albedo -- 20.2 sec chord
Diameter=214.3 km assuming a 30% albedo -- 8.2 sec chord
Dynamical classification is 3:2E
 
 
 
 
 
 
 
 

Star training set for 55638, (2023/12/15 14:38UT)
Object            RA         Dec     mag  sep  mel
Betelgeuse     05:56:28.2 +07:24:34  0.4 14.81 144
Alhena         06:39:05.7 +16:22:36  1.9 11.14 158
PPM 151677     07:00:37.7 +07:16:56  6.1  1.73 156
PPM 151571     06:57:42.6 +05:58:16  7.6  0.47 155
PPM 151491     06:55:43.4 +06:06:35  9.4  0.10 154
55638          06:55:50.8 +06:01:04 16.7       154
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 55638, (2023/12/15 14:38UT)
Object            RA         Dec     mag  sep  mel
Betelgeuse     05:55:10.3 +07:24:26  0.4 14.81 144
Alhena         06:37:42.8 +16:23:57  1.9 11.14 158
PPM 151677     06:59:20.1 +07:19:00  6.1  1.73 156
PPM 151571     06:56:25.7 +06:00:15  7.6  0.47 155
PPM 151491     06:54:26.4 +06:08:29  9.4  0.10 154
55638          06:54:33.8 +06:02:59 16.7       154
Positions are for J2000

Event circumstances last updated at 2023/12/06 05:55:21 UT

Marc W. Buie, Southwest Research Institute

RECON