RECON: TNO occultation with 91205

Event between (91205) 98US43 and star GA1040:01646640 with event index number of 1487677

Geocentric closest approach at 2025/12/18 19:33:43 UTC

J2000 position of star is 06:14:45.4 +15:04:16
Equinox of date position of star is 06:16:04.6 +15:03:45
Stellar brightness G=14.4, use SENSEUP=64 with the MallinCam and and exposure time of 1 seconds with the QHY174 camera.
Star is 156 degrees from the moon. Moon is 2% illuminated.
Apparent brightness V=24.0

Object is 38.5 AU from the Sun and 37.5 AU from the Earth.
Apparent velocity is 25.3 km/sec on the sky relative to the star, or, 3.3 arcsec/hr.
The 1-sigma error in the time of the event is 394 seconds.
The 1-sigma cross-track error in the shadow position is 2056 km.

The object has an absolute magnitude Hv=8.2
Diameter=151.4 km assuming a 5% albedo -- 5.3 sec chord
Diameter=61.8 km assuming a 30% albedo -- 2.2 sec chord
Dynamical classification is 3:2E
 
 
 
 
 
 
 
 

Star training set for 91205, (2025/12/18 19:27UT)
Object            RA         Dec     mag  sep  mel
Betelgeuse     05:56:34.7 +07:24:35  0.4  9.04 154
Alhena         06:39:12.7 +16:22:30  1.9  5.68 152
PPM 122243     06:19:34.3 +14:22:16  6.2  1.06 155
PPM 122143     06:15:57.4 +15:16:58  8.3  0.23 156
PPM 122157     06:16:17.2 +14:55:15 10.1  0.14 156
91205          06:16:14.6 +15:03:41 14.4       155
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 91205, (2025/12/18 19:27UT)
Object            RA         Dec     mag  sep  mel
Betelgeuse     05:55:10.3 +07:24:26  0.4  9.04 154
Alhena         06:37:42.8 +16:23:57  1.9  5.68 152
PPM 122243     06:18:05.6 +14:22:58  6.2  1.06 155
PPM 122143     06:14:28.1 +15:17:32  8.3  0.23 156
PPM 122157     06:14:48.2 +14:55:50 10.1  0.14 156
91205          06:14:45.4 +15:04:16 14.4       156
Positions are for J2000

Event circumstances last updated at 2023/01/24 02:44:26 UT

Marc W. Buie, Southwest Research Institute

RECON