RECON: TNO occultation with 160427

Event between (160427) 05RL43 and star GA1000:00776851 with event index number of 1967207

Geocentric closest approach at 2025/10/02 04:05:53 UTC

J2000 position of star is 05:26:29.1 +10:51:54
Equinox of date position of star is 05:27:48.9 +10:53:03
Stellar brightness G=16.2, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 135 degrees from the moon. Moon is 71% illuminated.
Apparent brightness V=22.1

Object is 24.8 AU from the Sun and 24.5 AU from the Earth.
Apparent velocity is 6.7 km/sec on the sky relative to the star, or, 1.4 arcsec/hr.
The 1-sigma error in the time of the event is 159 seconds.
The 1-sigma cross-track error in the shadow position is 1093 km.

The object has an absolute magnitude Hv=8.0
Diameter=155.6 km assuming a 5% albedo -- 22.9 sec chord
Diameter=63.5 km assuming a 30% albedo -- 9.3 sec chord
Dynamical classification is CENTAURR
 
 
 
 
 
 
 
 

Star training set for 160427, (2025/10/02 04:06UT)
Object            RA         Dec     mag  sep  mel
Betelgeuse     05:56:34.0 +07:24:35  0.4  7.88 140
Bellatrix      05:26:30.8 +06:22:15  1.6  4.53 132
PPM 121138     05:36:38.5 +10:15:18  5.7  2.24 136
PPM 120908     05:25:19.7 +11:06:20  8.2  0.67 134
PPM 120954     05:28:03.0 +11:17:54  9.4  0.41 135
PPM 120979     05:29:14.8 +10:53:32 10.4  0.33 135
160427         05:27:54.8 +10:53:08 16.2       135
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 160427, (2025/10/02 04:06UT)
Object            RA         Dec     mag  sep  mel
Betelgeuse     05:55:10.3 +07:24:26  0.4  7.88 140
Bellatrix      05:25:07.8 +06:20:58  1.6  4.53 132
PPM 121138     05:35:13.2 +10:14:24  5.7  2.24 136
PPM 120908     05:23:53.8 +11:05:01  8.2  0.67 134
PPM 120954     05:26:37.0 +11:16:40  9.4  0.41 135
PPM 120979     05:27:49.1 +10:52:21 10.4  0.33 135
160427         05:26:29.1 +10:51:54 16.2       135
Positions are for J2000

Event circumstances last updated at 2023/12/22 05:56:34 UT

Marc W. Buie, Southwest Research Institute

RECON