RECON: TNO occultation with 69990

Event between (69990) 98WU31 and star GA1080:01487052 with event index number of 352440

Geocentric closest approach at 2020/04/06 19:09:53 UTC

J2000 position of star is 05:55:10.3 +19:50:53
Equinox of date position of star is 05:56:20.7 +19:51:00
Stellar brightness G=11.0, use SENSEUP=4
Star is 90 degrees from the moon. Moon is 97% illuminated.
TNO apparent brightness V=23.8

TNO is 35.8 AU from the Sun and 36.1 AU from the Earth.
The TNO is moving 14.0 km/sec on the sky relative to the star, or, 1.9 arcsec/hr.
The 1-sigma error in the time of the event is 241 seconds.
The 1-sigma cross-track error in the shadow position is 1461 km.

The TNO has an absolute magnitude Hv=8.1
Diameter=144.5 km assuming a 5% albedo -- 10.3 sec chord
Diameter=59.0 km assuming a 30% albedo -- 4.2 sec chord
Dynamical classification is 3:2E
 
 
 
 
 
 
 
 

Star training set for 69990, (2020/04/06 19:10UT)
Object            RA         Dec     mag  sep  mel
Betelgeuse     05:56:16.2 +07:24:33  0.4 12.44  91
Alhena         06:38:52.9 +16:22:49  1.9 10.68  80
57 Ori         05:56:08.6 +19:45:06  5.6  0.11  90
PPM 121584     05:56:11.6 +19:36:24  8.4  0.25  90
57 Ori         05:56:08.6 +19:45:06  5.6  0.11  90
69990          05:56:22.4 +19:51:00 11.0        90
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, (2020/04/06 19:10UT)
Object            RA         Dec     mag  sep  mel
Betelgeuse     05:55:10.3 +07:24:26  0.4 12.44  91
Alhena         06:37:42.8 +16:23:57  1.9 10.68  80
57 Ori         05:54:56.6 +19:44:58  5.6  0.11  90
PPM 121584     05:54:59.6 +19:36:16  8.4  0.25  90
57 Ori         05:54:56.6 +19:44:58  5.6  0.11  90
69990          05:55:10.3 +19:50:53 11.0        90
Positions are for J2000

Event circumstances last updated at 2019/10/15 22:15:17 UT

Marc W. Buie, Southwest Research Institute

RECON