RECON: TNO occultation with 487581

Event between (487581) 15BE519 and star UC4-505-053719 with event index number of 186067

Geocentric closest approach at 2018/02/16 14:38:36 UTC

J2000 position of star is 11:16:54.5 +10:51:52
Equinox of date position of star is 11:17:50.4 +10:45:59
Stellar brightness R=16.0, use SENSEUP=128
Star is 170 degrees from the moon. Moon is 1% illuminated.
TNO apparent brightness V=22.2

TNO is 47.2 AU from the Sun and 46.2 AU from the Earth.
The TNO is moving 24.7 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 255 seconds.
The 1-sigma cross-track error in the shadow position is 4028 km.

The TNO has an absolute magnitude Hv=5.5
Diameter=478.6 km assuming a 5% albedo -- 19.4 sec chord
Diameter=195.4 km assuming a 30% albedo -- 7.9 sec chord
Dynamical classification is SCATNEAR
 
 
 
 
 
 
 
 

Star training set for 487581, (2018/02/16 14:39UT)
Object            RA         Dec     mag  sep  mel
Regulus        10:09:20.1 +11:52:41  1.3 16.83 174
Denebola       11:49:59.0 +14:28:14  2.1  8.67 161
PPM 128238     11:25:55.3 +11:19:50  5.8  2.06 168
PPM 128074     11:14:14.7 +10:20:54  8.2  0.98 170
PPM 128101     11:16:17.9 +10:50:42  9.4  0.39 170
PPM 128129     11:17:51.3 +10:29:21 10.2  0.28 170
487581         11:17:51.1 +10:45:55 16.0       169
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 487581, (2018/02/16 14:39UT)
Object            RA         Dec     mag  sep  mel
Regulus        10:08:22.0 +11:58:02  1.3 16.83 174
Denebola       11:49:03.0 +14:34:17  2.1  8.67 161
PPM 128238     11:24:58.8 +11:25:49  5.8  2.06 168
PPM 128074     11:13:18.1 +10:26:50  8.2  0.98 170
PPM 128101     11:15:21.3 +10:56:38  9.4  0.39 170
PPM 128129     11:16:54.8 +10:35:18 10.2  0.28 170
487581         11:16:54.5 +10:51:52 16.0       170
Positions are for J2000

Event circumstances last updated at 2017/12/02 17:17:05 UT

Marc W. Buie, Southwest Research Institute

RECON