RECON: TNO occultation with 508869

Event between (508869) 02VT130 and star GA1140:01657003 with event index number of 1494375

Geocentric closest approach at 2025/12/16 14:23:02 UTC

J2000 position of star is 05:56:56.9 +24:31:07
Equinox of date position of star is 05:58:21.9 +24:31:11
Stellar brightness G=16.5, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 138 degrees from the moon. Moon is 11% illuminated.
Apparent brightness V=22.1

Object is 43.3 AU from the Sun and 42.3 AU from the Earth.
Apparent velocity is 25.7 km/sec on the sky relative to the star, or, 3.0 arcsec/hr.
The 1-sigma error in the time of the event is 199 seconds.
The 1-sigma cross-track error in the shadow position is 1781 km.

The object has an absolute magnitude Hv=5.8
Diameter=436.5 km assuming a 5% albedo -- 15.9 sec chord
Diameter=178.2 km assuming a 30% albedo -- 6.5 sec chord
Dynamical classification is CLASSICAL
 
 
 
 
 
 
 
 

Star training set for 508869, (2025/12/16 14:23UT)
Object            RA         Dec     mag  sep  mel
Betelgeuse     05:56:34.7 +07:24:35  0.4 17.12 134
Alnath         05:27:56.1 +28:37:37  1.6  7.98 145
PPM 095124     05:58:31.5 +24:15:04  5.8  0.27 138
PPM 095144     05:59:12.6 +24:36:51  7.7  0.18 138
PPM 095119     05:58:16.1 +24:25:04  9.8  0.12 138
PPM 095126     05:58:39.3 +24:37:23 10.2  0.11 138
508869         05:58:32.5 +24:31:12 16.5       137
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 508869, (2025/12/16 14:23UT)
Object            RA         Dec     mag  sep  mel
Betelgeuse     05:55:10.3 +07:24:26  0.4 17.12 134
Alnath         05:26:17.6 +28:36:23  1.6  7.98 145
PPM 095124     05:56:56.1 +24:14:59  5.8  0.27 138
PPM 095144     05:57:36.9 +24:36:47  7.7  0.18 138
PPM 095119     05:56:40.5 +24:24:58  9.8  0.12 138
PPM 095126     05:57:03.6 +24:37:18 10.2  0.11 138
508869         05:56:56.9 +24:31:07 16.5       138
Positions are for J2000

Event circumstances last updated at 2023/01/24 02:42:00 UT

Marc W. Buie, Southwest Research Institute

RECON