RECON: TNO occultation with 42355

Event between (42355) Typhon and star GA0660:06814040 with event index number of 2412858

Geocentric closest approach at 2026/03/27 17:09:39 UTC

J2000 position of star is 15:54:27.7 -22:39:30
Equinox of date position of star is 15:55:54.6 -22:43:44
Stellar brightness G=16.4, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 120 degrees from the moon. Moon is 71% illuminated.
Apparent brightness V=22.0

Object is 26.6 AU from the Sun and 26.0 AU from the Earth.
Apparent velocity is 11.2 km/sec on the sky relative to the star, or, 2.1 arcsec/hr.
The 1-sigma error in the time of the event is 111 seconds.
The 1-sigma cross-track error in the shadow position is 962 km.

The object has an absolute magnitude Hv=7.6
Diameter=181.1 km assuming a 5% albedo -- 16.0 sec chord
Diameter=74.0 km assuming a 30% albedo -- 6.5 sec chord
Dynamical classification is CENTAURR
 
 
 
 
 
 
 
 

Star training set for 42355, (2026/03/27 17:10UT)
Object            RA         Dec     mag  sep  mel
Antares        16:31:01.2 -26:29:16  0.9  8.79 128
7Del Sco       16:01:53.4 -22:41:39  2.3  1.36 121
PPM 264830     15:55:29.9 -24:03:15  5.4  1.33 120
PPM 264845     15:56:14.9 -22:50:31  7.2  0.12 120
42355          15:56:00.9 -22:44:02 16.4       120
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 42355, (2026/03/27 17:10UT)
Object            RA         Dec     mag  sep  mel
Antares        16:29:24.4 -26:25:56  0.9  8.79 128
7Del Sco       16:00:20.0 -22:37:19  2.3  1.36 121
PPM 264830     15:53:55.9 -23:58:42  5.4  1.33 120
PPM 264845     15:54:41.6 -22:45:59  7.2  0.12 120
42355          15:54:27.7 -22:39:30 16.4       120
Positions are for J2000

Event circumstances last updated at 2024/06/18 21:26:00 UT

Marc W. Buie, Southwest Research Institute

RECON