RECON: TNO occultation with 307261

Event between (307261) 02MS4 and star GA0840:14393014 with event index number of 2184208

Geocentric closest approach at 2022/07/15 13:50:55 UTC

J2000 position of star is 18:57:43.8 -05:43:52
Equinox of date position of star is 18:58:54.9 -05:42:00
Stellar brightness G=12.9, use SENSEUP=32 with the MallinCam and and exposure time of 500 milli-seconds with the QHY174 camera.
Star is 40 degrees from the moon. Moon is 95% illuminated.
TNO apparent brightness V=20.5

TNO is 46.3 AU from the Sun and 45.4 AU from the Earth.
The TNO is moving 24.9 km/sec on the sky relative to the star, or, 2.7 arcsec/hr.
The 1-sigma error in the time of the event is 230 seconds.
The 1-sigma cross-track error in the shadow position is 2062 km.

The TNO has an absolute magnitude Hv=3.8
Diameter=1066.6 km assuming a 5% albedo -- 42.8 sec chord
Diameter=435.5 km assuming a 30% albedo -- 17.5 sec chord
Dynamical classification is SCATEXTD
 
 
 
 
 
 
 
 

Star training set for 307261, (2022/07/15 13:51UT)
Object            RA         Dec     mag  sep  mel
Antares        16:30:47.6 -26:28:48  0.9 40.95  69
Tarazed        19:47:19.8 +10:40:11  2.7 20.32  40
Eta Sct        18:58:16.1 -05:48:55  4.8  0.20  40
PPM 202320     18:57:04.9 -05:43:01  7.8  0.46  40
Eta Sct        18:58:16.1 -05:48:55  4.8  0.20  40
307261         18:58:56.0 -05:41:58 12.9        40
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 307261, (2022/07/15 13:51UT)
Object            RA         Dec     mag  sep  mel
Antares        16:29:24.4 -26:25:56  0.9 40.95  69
Tarazed        19:46:15.6 +10:36:48  2.7 20.32  40
Eta Sct        18:57:03.8 -05:50:48  4.8  0.20  40
PPM 202320     18:55:52.7 -05:44:51  7.8  0.46  40
Eta Sct        18:57:03.8 -05:50:48  4.8  0.20  40
307261         18:57:43.8 -05:43:52 12.9        40
Positions are for J2000

Event circumstances last updated at 2022/03/15 01:06:44 UT

Marc W. Buie, Southwest Research Institute

RECON