RECON: TNO occultation with 416400

Event between (416400) 03UZ117 and star GA0900:00593552 with event index number of 2376758

Geocentric closest approach at 2025/09/02 23:00:16 UTC

J2000 position of star is 05:12:15.7 +01:02:25
Equinox of date position of star is 05:13:30.7 +01:04:04
Stellar brightness G=15.5, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 145 degrees from the moon. Moon is 75% illuminated.
Apparent brightness V=21.2

Object is 38.5 AU from the Sun and 38.6 AU from the Earth.
Apparent velocity is 14.7 km/sec on the sky relative to the star, or, 1.9 arcsec/hr.
The 1-sigma error in the time of the event is 109 seconds.
The 1-sigma cross-track error in the shadow position is 1611 km.

The object has an absolute magnitude Hv=5.2
Diameter=522.4 km assuming a 5% albedo -- 36.5 sec chord
Diameter=213.3 km assuming a 30% albedo -- 14.9 sec chord
Dynamical classification is SCATEXTD
 
 
 
 
 
 
 
 

Star training set for 416400, (2025/09/02 22:57UT)
Object            RA         Dec     mag  sep  mel
Rigel          05:15:46.4 -08:10:26  0.1  9.26 137
34Del Ori      05:33:19.2 -00:16:56  2.2  5.11 146
PPM 148621     05:14:51.6 +01:59:45  6.4  0.98 145
PPM 148581     05:13:04.9 +01:03:58  6.7  0.13 144
416400         05:13:35.3 +01:04:10 15.5       145
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 416400, (2025/09/02 22:57UT)
Object            RA         Dec     mag  sep  mel
Rigel          05:14:32.3 -08:12:06  0.1  9.26 137
34Del Ori      05:32:00.4 -00:17:57  2.2  5.11 146
PPM 148621     05:13:31.5 +01:58:03  6.4  0.98 145
PPM 148581     05:11:45.3 +01:02:12  6.7  0.13 144
416400         05:12:15.7 +01:02:25 15.5       144
Positions are for J2000

Event circumstances last updated at 2024/03/04 05:36:02 UT

Marc W. Buie, Southwest Research Institute

RECON