RECON: TNO occultation with 12HW87

Event between 12HW87 and star GA0740:10740681 with event index number of 2156282

Geocentric closest approach at 2022/07/12 20:55:55 UTC

J2000 position of star is 17:42:40.9 -14:07:59
Equinox of date position of star is 17:43:56.7 -14:08:31
Stellar brightness G=14.7, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 18 degrees from the moon. Moon is 99% illuminated.
TNO apparent brightness V=23.0

TNO is 34.0 AU from the Sun and 33.1 AU from the Earth.
The TNO is moving 20.6 km/sec on the sky relative to the star, or, 3.1 arcsec/hr.
The 1-sigma error in the time of the event is 326 seconds.
The 1-sigma cross-track error in the shadow position is 1977 km.

The TNO has an absolute magnitude Hv=7.6
Diameter=184.5 km assuming a 5% albedo -- 9.0 sec chord
Diameter=75.3 km assuming a 30% albedo -- 3.7 sec chord
Dynamical classification is SCATNEAR
 
 
 
 
 
 
 
 

Star training set for 12HW87, (2022/07/12 20:56UT)
Object            RA         Dec     mag  sep  mel
Antares        16:30:47.5 -26:28:48  0.9 21.09  28
35Eta Oph      17:11:40.3 -15:45:04  2.6  7.96  22
56Omi Ser      17:42:40.9 -12:53:07  4.4  1.29  19
PPM 233476     17:43:22.0 -13:56:59  8.3  0.24  18
PPM 233472     17:43:13.5 -14:09:15  9.4  0.18  18
12HW87         17:43:57.8 -14:08:32 14.7        17
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 12HW87, (2022/07/12 20:56UT)
Object            RA         Dec     mag  sep  mel
Antares        16:29:24.4 -26:25:56  0.9 21.09  28
35Eta Oph      17:10:22.7 -15:43:29  2.6  7.96  22
56Omi Ser      17:41:24.8 -12:52:32  4.4  1.29  19
PPM 233476     17:42:05.2 -13:56:25  8.3  0.24  18
PPM 233472     17:41:56.6 -14:08:41  9.4  0.18  18
12HW87         17:42:40.9 -14:07:59 14.7        17
Positions are for J2000

Event circumstances last updated at 2022/03/14 01:05:37 UT

Marc W. Buie, Southwest Research Institute

RECON