RECON: TNO occultation with 118228

Event between (118228) 96TQ66 and star GA1260:01608550 with event index number of 2111100

Geocentric closest approach at 2026/03/26 23:49:01 UTC

J2000 position of star is 05:01:08.5 +36:24:26
Equinox of date position of star is 05:02:46.2 +36:26:28
Stellar brightness G=16.7, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 35 degrees from the moon. Moon is 63% illuminated.
Apparent brightness V=22.9

Object is 36.0 AU from the Sun and 36.3 AU from the Earth.
Apparent velocity is 15.3 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 426 seconds.
The 1-sigma cross-track error in the shadow position is 2188 km.

The object has an absolute magnitude Hv=7.2
Diameter=224.9 km assuming a 5% albedo -- 14.5 sec chord
Diameter=91.8 km assuming a 30% albedo -- 5.9 sec chord
Dynamical classification is 3:2E
 
 
 
 
 
 
 
 

Star training set for 118228, (2026/03/26 23:49UT)
Object            RA         Dec     mag  sep  mel
Aldebaran      04:37:25.7 +16:33:36  0.8 20.67  43
3Iot Aur       04:58:42.4 +33:12:18  2.7  3.35  35
PPM 069764     04:58:05.4 +36:12:29  6.0  1.00  36
PPM 069821     05:02:19.2 +36:39:51  7.3  0.25  35
PPM 069829     05:02:46.5 +36:17:17 10.1  0.16  35
118228         05:02:54.3 +36:26:38 16.7        34
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 118228, (2026/03/26 23:49UT)
Object            RA         Dec     mag  sep  mel
Aldebaran      04:35:55.3 +16:30:29  0.8 20.67  43
3Iot Aur       04:56:59.6 +33:09:58  2.7  3.35  35
PPM 069764     04:56:20.0 +36:10:07  6.0  1.00  36
PPM 069821     05:00:33.3 +36:37:38  7.3  0.25  35
PPM 069829     05:01:01.0 +36:15:05 10.1  0.16  35
118228         05:01:08.5 +36:24:26 16.7        35
Positions are for J2000

Event circumstances last updated at 2024/03/21 22:30:49 UT

Marc W. Buie, Southwest Research Institute

RECON