RECON: TNO occultation with 278361

Event between (278361) 07JJ43 and star GA0620:11853457 with event index number of 1154778

Geocentric closest approach at 2021/06/26 11:05:25 UTC

J2000 position of star is 17:01:18.6 -26:04:06
Equinox of date position of star is 17:02:36.7 -26:05:52
Stellar brightness G=13.9, use SENSEUP=64 with the MallinCam and and exposure time of 1 seconds with the QHY174 camera.
Star is 41 degrees from the moon. Moon is 96% illuminated.
TNO apparent brightness V=20.6

TNO is 40.8 AU from the Sun and 39.8 AU from the Earth.
The TNO is moving 23.0 km/sec on the sky relative to the star, or, 2.9 arcsec/hr.
The 1-sigma error in the time of the event is 276 seconds.
The 1-sigma cross-track error in the shadow position is 2590 km.

The TNO has an absolute magnitude Hv=4.5
Diameter=758.6 km assuming a 5% albedo -- 32.9 sec chord
Diameter=309.7 km assuming a 30% albedo -- 13.4 sec chord
Dynamical classification is SCATNEAR
 
 
 
 
 
 
 
 

Star training set for 278361, (2021/06/26 11:05UT)
Object            RA         Dec     mag  sep  mel
Antares        16:30:43.7 -26:28:40  0.9  7.16  48
23Tau Sco      16:37:13.4 -28:15:32  2.8  6.05  47
26 Oph         17:01:28.6 -25:01:12  5.8  1.11  42
PPM 266235     17:00:47.3 -26:24:14  8.5  0.52  42
PPM 266282     17:02:43.3 -25:46:12  9.2  0.33  41
PPM 266303     17:03:26.3 -26:21:37 10.1  0.32  41
278361         17:02:38.2 -26:05:54 13.9        41
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 278361, (2021/06/26 11:05UT)
Object            RA         Dec     mag  sep  mel
Antares        16:29:24.4 -26:25:56  0.9  7.16  48
23Tau Sco      16:35:52.9 -28:12:58  2.8  6.05  47
26 Oph         17:00:09.6 -24:59:22  5.8  1.11  42
PPM 266235     16:59:27.5 -26:22:23  8.5  0.52  42
PPM 266282     17:01:23.8 -25:44:24  9.2  0.33  41
PPM 266303     17:02:06.5 -26:19:51 10.1  0.32  41
278361         17:01:18.6 -26:04:06 13.9        41
Positions are for J2000

Event circumstances last updated at 2021/01/22 21:29:16 UT

Marc W. Buie, Southwest Research Institute

RECON