RECON: TNO occultation with 38084

Event between (38084) 99HB12 and star UC4-416-062383 with event index number of 100801

Geocentric closest approach at 2018/01/24 17:47:41 UTC

J2000 position of star is 15:29:23.1 -06:51:35
Equinox of date position of star is 15:30:20.5 -06:55:14
Stellar brightness R=14.5, use SENSEUP=128
Star is 160 degrees from the moon. Moon is 48% illuminated.
TNO apparent brightness V=22.3

TNO is 32.6 AU from the Sun and 32.8 AU from the Earth.
The TNO is moving 16.6 km/sec on the sky relative to the star, or, 2.5 arcsec/hr.
The 1-sigma error in the time of the event is 257 seconds.
The 1-sigma cross-track error in the shadow position is 1943 km.

The TNO has an absolute magnitude Hv=7.0
Diameter=239.9 km assuming a 5% albedo -- 14.4 sec chord
Diameter=97.9 km assuming a 30% albedo -- 5.9 sec chord
Dynamical classification is 5:2EEE
 
 
 
 
 
 
 
 

Star training set for 38084, (2018/01/24 17:48UT)
Object            RA         Dec     mag  sep  mel
Antares        16:30:31.1 -26:28:14  0.9 24.23 141
27Bet Lib      15:17:58.9 -09:26:55  2.6  3.97 163
PPM 198488     15:22:05.0 -05:53:21  5.4  2.30 162
PPM 198655     15:31:02.8 -06:54:22  7.4  0.17 160
PPM 198647     15:30:07.7 -07:02:26  8.6  0.13 160
38084          15:30:21.0 -06:55:16 14.5       159
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 38084, (2018/01/24 17:48UT)
Object            RA         Dec     mag  sep  mel
Antares        16:29:24.4 -26:25:56  0.9 24.23 141
27Bet Lib      15:17:00.3 -09:22:59  2.6  3.97 163
PPM 198488     15:21:07.5 -05:49:30  5.4  2.30 162
PPM 198655     15:30:04.9 -06:50:42  7.4  0.17 160
PPM 198647     15:29:09.8 -06:58:45  8.6  0.13 160
38084          15:29:23.1 -06:51:35 14.5       160
Positions are for J2000

Event circumstances last updated at 2017/12/02 17:12:57 UT

Marc W. Buie, Southwest Research Institute

RECON