RECON: TNO occultation with 8405

Event between (8405) Asbolus and star GA1300:03496546 with event index number of 1510878

Geocentric closest approach at 2025/11/24 15:04:37 UTC

J2000 position of star is 06:24:29.1 +41:31:02
Equinox of date position of star is 06:26:11.9 +41:30:09
Stellar brightness G=15.5, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 159 degrees from the moon. Moon is 16% illuminated.
Apparent brightness V=23.4

Object is 25.9 AU from the Sun and 25.1 AU from the Earth.
Apparent velocity is 22.4 km/sec on the sky relative to the star, or, 4.4 arcsec/hr.
The 1-sigma error in the time of the event is 143 seconds.
The 1-sigma cross-track error in the shadow position is 1180 km.

The object has an absolute magnitude Hv=9.2
Diameter=91.2 km assuming a 5% albedo -- 3.9 sec chord
Diameter=37.2 km assuming a 30% albedo -- 1.6 sec chord
Dynamical classification is CENTAURR
 
 
 
 
 
 
 
 

Star training set for 8405, (2025/11/24 15:05UT)
Object            RA         Dec     mag  sep  mel
Pollux         07:46:54.0 +27:57:41  1.1 21.29 176
34Bet Aur      06:01:25.8 +44:56:50  1.9  5.69 154
50Psi2Aur      06:41:10.6 +42:27:48  5.9  2.92 160
PPM 049043     06:27:46.9 +41:34:36  8.5  0.28 160
PPM 049028     06:26:39.5 +41:16:49 10.2  0.23 160
8405           06:26:19.2 +41:30:05 15.5       160
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 8405, (2025/11/24 15:05UT)
Object            RA         Dec     mag  sep  mel
Pollux         07:45:17.9 +28:01:33  1.1 21.29 176
34Bet Aur      05:59:31.6 +44:56:51  1.9  5.69 154
50Psi2Aur      06:39:19.8 +42:29:19  5.9  2.92 160
PPM 049043     06:25:56.8 +41:35:36  8.5  0.28 160
PPM 049028     06:24:49.7 +41:17:47 10.2  0.23 160
8405           06:24:29.1 +41:31:02 15.5       159
Positions are for J2000

Event circumstances last updated at 2024/03/03 06:06:17 UT

Marc W. Buie, Southwest Research Institute

RECON