RECON: TNO occultation with 28978

Event between (28978) Ixion and star GA0580:36585555 with event index number of 1480697

Geocentric closest approach at 2025/10/15 10:07:43 UTC

J2000 position of star is 18:23:15.2 -31:58:49
Equinox of date position of star is 18:24:49.6 -31:57:58
Stellar brightness G=15.4, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 142 degrees from the moon. Moon is 33% illuminated.
Apparent brightness V=19.4

Object is 37.6 AU from the Sun and 37.9 AU from the Earth.
Apparent velocity is 14.0 km/sec on the sky relative to the star, or, 1.8 arcsec/hr.
The 1-sigma error in the time of the event is 407 seconds.
The 1-sigma cross-track error in the shadow position is 2148 km.

The object has an absolute magnitude Hv=3.5
Diameter=1148.2 km assuming a 5% albedo -- 87.0 sec chord
Diameter=468.7 km assuming a 30% albedo -- 35.5 sec chord
Dynamical classification is 3:2E
 
 
 
 
 
 
 
 

Star training set for 28978, (2025/10/15 10:08UT)
Object            RA         Dec     mag  sep  mel
Antares        16:30:59.6 -26:29:13  0.9 25.38 117
38Zet Sgr      19:04:15.0 -29:50:27  2.7  8.69 151
18 Sgr         18:26:40.8 -30:44:28  5.3  1.28 142
PPM 297610     18:24:05.6 -32:11:59  8.3  0.29 142
PPM 297611     18:24:07.7 -31:55:16  9.9  0.18 142
28978          18:24:55.9 -31:57:55 15.4       142
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 28978, (2025/10/15 10:08UT)
Object            RA         Dec     mag  sep  mel
Antares        16:29:24.4 -26:25:56  0.9 25.38 117
38Zet Sgr      19:02:36.7 -29:52:49  2.7  8.69 151
18 Sgr         18:25:01.2 -30:45:26  5.3  1.28 142
PPM 297610     18:22:24.7 -32:12:52  8.3  0.29 142
PPM 297611     18:22:27.1 -31:56:09  9.9  0.18 142
28978          18:23:15.2 -31:58:49 15.4       142
Positions are for J2000

Event circumstances last updated at 2024/03/03 06:00:12 UT

Marc W. Buie, Southwest Research Institute

RECON