RECON: TNO occultation with 181871

Event between (181871) 99CO153 and star GA1000:03415533 with event index number of 248045

Geocentric closest approach at 2020/02/23 13:42:00 UTC

J2000 position of star is 10:11:08.4 +10:30:41
Equinox of date position of star is 10:12:07.2 +10:25:12
Stellar brightness G=15.0, use SENSEUP=128
Star is 175 degrees from the moon. Moon is 0% illuminated.
TNO apparent brightness V=23.6

TNO is 42.3 AU from the Sun and 41.3 AU from the Earth.
The TNO is moving 25.5 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 452 seconds.
The 1-sigma cross-track error in the shadow position is 5287 km.

The TNO has an absolute magnitude Hv=7.4
Diameter=199.5 km assuming a 5% albedo -- 7.8 sec chord
Diameter=81.5 km assuming a 30% albedo -- 3.2 sec chord
Dynamical classification is 7:4EEE
 
 
 
 
 
 
 
 

Star training set for 181871, (2020/02/23 13:42UT)
Object            RA         Dec     mag  sep  mel
Regulus        10:09:26.6 +11:52:05  1.3  1.61 175
31 Leo         10:08:58.3 +09:53:53  6.0  0.95 174
PPM 127205     10:13:38.2 +10:11:50  9.0  0.41 175
PPM 127180     10:12:15.2 +10:22:59 10.9  0.03 174
181871         10:12:12.6 +10:24:41 15.0       175
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 181871, (2020/02/23 13:42UT)
Object            RA         Dec     mag  sep  mel
Regulus        10:08:22.0 +11:58:02  1.3  1.61 175
31 Leo         10:07:54.2 +09:59:50  6.0  0.95 174
PPM 127205     10:12:34.1 +10:17:50  9.0  0.41 175
PPM 127180     10:11:11.0 +10:28:59 10.9  0.03 174
181871         10:11:08.4 +10:30:41 15.0       174
Positions are for J2000

Event circumstances last updated at 2018/06/12 19:54:34 UT

Marc W. Buie, Southwest Research Institute

RECON