RECON: TNO occultation with 278361

Event between (278361) 07JJ43 and star GA0640:18891692 with event index number of 2182835

Geocentric closest approach at 2027/06/08 22:34:08 UTC

J2000 position of star is 17:43:04.8 -24:49:13
Equinox of date position of star is 17:44:34.1 -24:49:47
Stellar brightness G=15.7, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 131 degrees from the moon. Moon is 23% illuminated.
Apparent brightness V=20.5

Object is 40.5 AU from the Sun and 39.5 AU from the Earth.
Apparent velocity is 24.1 km/sec on the sky relative to the star, or, 3.0 arcsec/hr.
The 1-sigma error in the time of the event is 389 seconds.
The 1-sigma cross-track error in the shadow position is 2676 km.

The object has an absolute magnitude Hv=4.5
Diameter=758.6 km assuming a 5% albedo -- 31.6 sec chord
Diameter=309.7 km assuming a 30% albedo -- 12.9 sec chord
Dynamical classification is SCATNEAR
 
 
 
 
 
 
 
 

Star training set for 278361, (2027/06/08 22:16UT)
Object            RA         Dec     mag  sep  mel
Antares        16:31:05.7 -26:29:25  0.9 16.67 115
35Eta Oph      17:11:57.2 -15:45:25  2.6 11.89 123
PPM 267309     17:49:25.1 -22:29:08  6.1  2.58 133
PPM 267267     17:48:06.1 -24:08:59  8.4  1.02 132
PPM 267167     17:44:10.6 -25:00:30  9.3  0.22 131
278361         17:44:46.1 -24:49:51 15.7       132
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, (2027/06/08 22:16UT)
Object            RA         Dec     mag  sep  mel
Antares        16:29:24.4 -26:25:56  0.9 16.67 115
35Eta Oph      17:10:22.7 -15:43:29  2.6 11.89 123
PPM 267309     17:47:45.6 -22:28:40  6.1  2.58 133
PPM 267267     17:46:25.3 -24:08:29  8.4  1.02 132
PPM 267167     17:42:29.2 -24:59:50  9.3  0.22 131
278361         17:43:04.8 -24:49:13 15.7       132
Positions are for J2000

Event circumstances last updated at 2024/03/06 04:23:59 UT

Marc W. Buie, Southwest Research Institute

RECON