RECON: TNO occultation with 69990

Event between (69990) 98WU31 and star GA1060:02535092 with event index number of 1795554

Geocentric closest approach at 2027/12/03 02:27:36 UTC

J2000 position of star is 06:58:35.7 +17:53:07
Equinox of date position of star is 07:00:01.2 +17:51:01
Stellar brightness G=8.9, use SENSEUP=2 with the MallinCam and and exposure time of 125 milli-seconds with the QHY174 camera.
Star is 157 degrees from the moon. Moon is 22% illuminated.
Apparent brightness V=24.0

Object is 37.2 AU from the Sun and 36.4 AU from the Earth.
Apparent velocity is 20.5 km/sec on the sky relative to the star, or, 2.8 arcsec/hr.
The 1-sigma error in the time of the event is 1021 seconds.
The 1-sigma cross-track error in the shadow position is 5110 km.

The object has an absolute magnitude Hv=8.2
Diameter=144.5 km assuming a 5% albedo -- 6.8 sec chord
Diameter=59.0 km assuming a 30% albedo -- 2.8 sec chord
Dynamical classification is 3:2E
 
 
 
 
 
 
 
 

Star training set for 69990, (2027/12/03 02:28UT)
Object            RA         Dec     mag  sep  mel
Pollux         07:47:01.5 +27:57:23  1.1 14.76 165
Alhena         06:39:19.5 +16:22:23  1.9  5.20 151
PPM 123373     07:01:54.0 +15:29:38  6.4  2.39 157
PPM 123314     06:59:20.5 +17:51:45  6.7  0.21 156
PPM 123350     07:00:57.9 +17:47:21  9.3  0.19 157
69990          07:00:13.2 +17:50:44  8.9       157
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 69990, (2027/12/03 02:28UT)
Object            RA         Dec     mag  sep  mel
Pollux         07:45:17.9 +28:01:33  1.1 14.76 165
Alhena         06:37:42.8 +16:23:57  1.9  5.20 151
PPM 123373     07:00:18.1 +15:32:06  6.4  2.39 157
PPM 123314     06:57:43.0 +17:54:07  6.7  0.21 156
PPM 123350     06:59:20.5 +17:49:46  9.3  0.19 157
69990          06:58:35.7 +17:53:07  8.9       157
Positions are for J2000

Event circumstances last updated at 2024/06/22 21:29:22 UT

Marc W. Buie, Southwest Research Institute

RECON