RECON: TNO occultation with 16684

Event between (16684) 94JQ1 and star GA0640:08219466 with event index number of 1643683

Geocentric closest approach at 2026/04/24 20:17:20 UTC

J2000 position of star is 16:41:46.2 -24:59:12
Equinox of date position of star is 16:43:15.8 -25:01:54
Stellar brightness G=16.0, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 118 degrees from the moon. Moon is 58% illuminated.
Apparent brightness V=23.0

Object is 42.1 AU from the Sun and 41.3 AU from the Earth.
Apparent velocity is 18.4 km/sec on the sky relative to the star, or, 2.2 arcsec/hr.
The 1-sigma error in the time of the event is 657 seconds.
The 1-sigma cross-track error in the shadow position is 2985 km.

The object has an absolute magnitude Hv=6.7
Diameter=270.4 km assuming a 5% albedo -- 14.9 sec chord
Diameter=110.4 km assuming a 30% albedo -- 6.1 sec chord
Dynamical classification is CLASSICAL
 
 
 
 
 
 
 
 

Star training set for 16684, (2026/04/24 20:17UT)
Object            RA         Dec     mag  sep  mel
Antares        16:31:01.5 -26:29:17  0.9  3.14 116
23Tau Sco      16:37:31.5 -28:16:06  2.8  3.49 118
22 Sco         16:31:48.7 -25:10:15  4.5  2.62 116
PPM 265814     16:43:45.5 -24:52:03  8.4  0.19 118
16684          16:43:22.6 -25:02:07 16.0       119
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 16684, (2026/04/24 20:17UT)
Object            RA         Dec     mag  sep  mel
Antares        16:29:24.4 -26:25:56  0.9  3.14 116
23Tau Sco      16:35:52.9 -28:12:58  2.8  3.49 118
22 Sco         16:30:12.5 -25:06:55  4.5  2.62 116
PPM 265814     16:42:09.2 -24:49:09  8.4  0.19 118
16684          16:41:46.2 -24:59:12 16.0       118
Positions are for J2000

Event circumstances last updated at 2024/06/09 02:46:30 UT

Marc W. Buie, Southwest Research Institute

RECON