RECON: TNO occultation with 55638

Event between (55638) 02VE95 and star GA0960:01961910 with event index number of 2249676

Geocentric closest approach at 2023/03/06 00:57:26 UTC

J2000 position of star is 06:38:24.1 +06:42:30
Equinox of date position of star is 06:39:38.9 +06:41:11
Stellar brightness G=12.9, use SENSEUP=32 with the MallinCam and and exposure time of 500 milli-seconds with the QHY174 camera.
Star is 53 degrees from the moon. Moon is 98% illuminated.
Apparent brightness V=20.7

Object is 30.9 AU from the Sun and 30.5 AU from the Earth.
Apparent velocity is 10.4 km/sec on the sky relative to the star, or, 1.7 arcsec/hr.
The 1-sigma error in the time of the event is 150 seconds.
The 1-sigma cross-track error in the shadow position is 1637 km.

The object has an absolute magnitude Hv=5.6
Diameter=524.8 km assuming a 5% albedo -- 44.3 sec chord
Diameter=214.3 km assuming a 30% albedo -- 18.1 sec chord
Dynamical classification is 3:2E
 
 
 
 
 
 
 
 

Star training set for 55638, (2023/03/06 00:57UT)
Object            RA         Dec     mag  sep  mel
Betelgeuse     05:56:25.6 +07:24:34  0.4 10.75  63
Alhena         06:39:03.0 +16:22:39  1.9  9.69  51
PPM 151014     06:41:46.6 +06:20:54  6.2  0.63  52
PPM 150946     06:40:02.9 +06:52:47  6.6  0.22  52
PPM 150905     06:39:06.3 +06:39:42  8.9  0.14  53
55638          06:39:38.9 +06:41:11 12.9        52
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, (2023/03/06 00:57UT)
Object            RA         Dec     mag  sep  mel
Betelgeuse     05:55:10.3 +07:24:26  0.4 10.75  63
Alhena         06:37:42.8 +16:23:57  1.9  9.69  51
PPM 151014     06:40:32.0 +06:22:17  6.2  0.63  52
PPM 150946     06:38:47.9 +06:54:06  6.6  0.22  52
PPM 150905     06:37:51.5 +06:41:00  8.9  0.14  53
55638          06:38:24.1 +06:42:30 12.9        53
Positions are for J2000

Event circumstances last updated at 2023/03/04 03:44:58 UT

Marc W. Buie, Southwest Research Institute

RECON