RECON: TNO occultation with 91554

Event between (91554) 99RZ215 and star GA1120:00098605 with event index number of 2629395

Geocentric closest approach at 2027/09/23 16:12:18 UTC

J2000 position of star is 00:46:36.0 +23:09:37
Equinox of date position of star is 00:47:54.1 +23:17:37
Stellar brightness G=15.2, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 73 degrees from the moon. Moon is 47% illuminated.
Apparent brightness V=23.6

Object is 40.6 AU from the Sun and 39.7 AU from the Earth.
Apparent velocity is 23.5 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 181 seconds.
The 1-sigma cross-track error in the shadow position is 4240 km.

The object has an absolute magnitude Hv=7.5
Diameter=166.0 km assuming a 5% albedo -- 8.1 sec chord
Diameter=67.8 km assuming a 30% albedo -- 3.3 sec chord
Dynamical classification is CENTAURR
 
 
 
 
 
 
 
 

Star training set for 91554, (2027/09/23 16:12UT)
Object            RA         Dec     mag  sep  mel
Deneb          20:42:22.7 +45:22:50  1.3 53.83 101
Algenib        00:14:40.0 +15:20:15  2.8 11.20  84
34Zet And      00:48:48.9 +24:25:03  4.1  1.12  73
PPM 090108     00:46:41.3 +23:44:31  7.2  0.54  74
PPM 090143     00:48:29.4 +23:24:05  8.9  0.13  73
PPM 090138     00:48:05.1 +23:22:49 10.9  0.07  73
91554          00:48:04.5 +23:18:41 15.2        73
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 91554, (2027/09/23 16:12UT)
Object            RA         Dec     mag  sep  mel
Deneb          20:41:25.9 +45:16:49  1.3 53.83 101
Algenib        00:13:14.2 +15:11:01  2.8 11.20  84
34Zet And      00:47:20.2 +24:16:00  4.1  1.12  73
PPM 090108     00:45:12.8 +23:35:27  7.2  0.54  74
PPM 090143     00:47:00.9 +23:15:01  8.9  0.13  73
PPM 090138     00:46:36.6 +23:13:46 10.9  0.07  73
91554          00:46:36.0 +23:09:37 15.2        73
Positions are for J2000

Event circumstances last updated at 2024/06/22 21:28:35 UT

Marc W. Buie, Southwest Research Institute

RECON