RECON: TNO occultation with 342842

Event between (342842) 08YB3 and star GA1200:08372994 with event index number of 2204366

Geocentric closest approach at 2025/09/16 00:16:21 UTC

J2000 position of star is 19:43:17.5 +30:02:54
Equinox of date position of star is 19:44:15.0 +30:06:26
Stellar brightness G=16.0, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 122 degrees from the moon. Moon is 33% illuminated.
Apparent brightness V=21.7

Object is 15.9 AU from the Sun and 15.4 AU from the Earth.
Apparent velocity is 31.2 km/sec on the sky relative to the star, or, 10.1 arcsec/hr.
The 1-sigma error in the time of the event is 49 seconds.
The 1-sigma cross-track error in the shadow position is 1019 km.

The object has an absolute magnitude Hv=9.5
Diameter=82.8 km assuming a 5% albedo -- 2.5 sec chord
Diameter=33.8 km assuming a 30% albedo -- 1.0 sec chord
Dynamical classification is CENTAURR
 
 
 
 
 
 
 
 

Star training set for 342842, (2025/09/16 00:16UT)
Object            RA         Dec     mag  sep  mel
Vega           18:37:48.5 +38:48:31  0.0 16.19 113
37Gam Cyg      20:23:09.1 +40:20:25  2.2 12.93 110
12Phi Cyg      19:40:23.5 +30:12:50  5.8  0.85 122
PPM 083423     19:44:16.1 +30:17:42  7.3  0.18 121
PPM 083445     19:44:58.0 +30:06:43  8.8  0.14 122
342842         19:44:18.7 +30:06:39 16.0       121
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 342842, (2025/09/16 00:16UT)
Object            RA         Dec     mag  sep  mel
Vega           18:36:56.7 +38:47:07  0.0 16.19 113
37Gam Cyg      20:22:13.7 +40:15:24  2.2 12.93 110
12Phi Cyg      19:39:22.6 +30:09:13  5.8  0.85 122
PPM 083423     19:43:15.1 +30:13:57  7.3  0.18 121
PPM 083445     19:43:56.8 +30:02:56  8.8  0.14 122
342842         19:43:17.5 +30:02:54 16.0       122
Positions are for J2000

Event circumstances last updated at 2024/03/03 05:54:58 UT

Marc W. Buie, Southwest Research Institute

RECON