RECON: TNO occultation with 120216

Event between (120216) 04EW95 and star GA0540:07818572 with event index number of 1098900

Geocentric closest approach at 2021/04/12 02:31:49 UTC

J2000 position of star is 15:21:05.8 -35:10:12
Equinox of date position of star is 15:22:25.9 -35:14:41
Stellar brightness G=15.6, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 140 degrees from the moon. Moon is 0% illuminated.
TNO apparent brightness V=21.0

TNO is 27.0 AU from the Sun and 26.3 AU from the Earth.
The TNO is moving 19.7 km/sec on the sky relative to the star, or, 3.7 arcsec/hr.
The 1-sigma error in the time of the event is 74 seconds.
The 1-sigma cross-track error in the shadow position is 1358 km.

The TNO has an absolute magnitude Hv=6.6
Diameter=287.1 km assuming a 5% albedo -- 14.6 sec chord
Diameter=117.2 km assuming a 30% albedo -- 6.0 sec chord
Dynamical classification is 3:2E
 
 
 
 
 
 
 
 

Star training set for 120216, (2021/04/12 02:32UT)
Object            RA         Dec     mag  sep  mel
Antares        16:30:42.9 -26:28:39  0.9 17.04 132
Eta Lup        16:01:32.3 -38:27:20  2.8  8.45 132
Phi2Lup        15:24:31.3 -36:56:00  4.5  1.74 139
PPM 293724     15:21:34.1 -35:00:05  8.1  0.30 141
PPM 293741     15:22:45.8 -35:15:42  9.3  0.07 140
120216         15:22:26.7 -35:14:43 15.6       140
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 120216, (2021/04/12 02:32UT)
Object            RA         Dec     mag  sep  mel
Antares        16:29:24.4 -26:25:56  0.9 17.04 132
Eta Lup        16:00:07.3 -38:23:48  2.8  8.45 132
Phi2Lup        15:23:09.3 -36:51:31  4.5  1.74 139
PPM 293724     15:20:13.3 -34:55:32  8.1  0.30 141
PPM 293741     15:21:24.9 -35:11:11  9.3  0.07 140
120216         15:21:05.8 -35:10:12 15.6       140
Positions are for J2000

Event circumstances last updated at 2021/01/20 20:10:24 UT

Marc W. Buie, Southwest Research Institute

RECON