Event between (385199) 99OE4 and star GA0840:20028354 with event index number of 2414449
Geocentric closest approach at 2025/09/15 16:55:40 UTC
J2000 position of star is 23:24:47.2 -05:18:15
Equinox of date position of star is 23:25:54.9 -05:11:01
Stellar brightness G=16.1,
use SENSEUP=128 with the MallinCam and and exposure
time of 2 seconds with the QHY174 camera.
Star is 110 degrees from the moon.
Moon is 36% illuminated.
TNO apparent brightness V=22.6
TNO is 43.3 AU from the Sun
and 42.3 AU from the Earth.
The TNO is moving 24.9
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 279 seconds.
The 1-sigma cross-track error in the shadow position is
4053 km.
The TNO has an absolute magnitude Hv=6.3
Diameter=263.0 km assuming a 5% albedo -- 13.0 sec chord
Diameter=107.4 km assuming a 30% albedo -- 5.3 sec chord
Dynamical classification is CLASSICAL
Star training set for 385199, (2025/09/15 16:56UT) Object RA Dec mag sep mel Fomalhaut 22:59:03.8 -29:29:07 1.2 25.15 125 Markab 23:06:02.6 +15:20:39 2.5 21.10 103 PPM 207450 23:22:00.4 -05:46:02 6.0 1.19 111 PPM 207558 23:27:59.5 -05:05:25 8.4 0.47 109 PPM 207529 23:26:19.2 -05:04:13 8.8 0.11 110 385199 23:26:06.7 -05:09:46 16.1 109 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 385199, (2025/09/15 16:56UT) Object RA Dec mag sep mel Fomalhaut 22:57:39.6 -29:37:24 1.2 25.15 125 Markab 23:04:45.8 +15:12:18 2.5 21.10 103 PPM 207450 23:20:40.8 -05:54:30 6.0 1.19 111 PPM 207558 23:26:40.0 -05:13:55 8.4 0.47 109 PPM 207529 23:24:59.7 -05:12:43 8.8 0.11 110 385199 23:24:47.2 -05:18:15 16.1 110 Positions are for J2000
Event circumstances last updated at 2021/11/27 00:14:12 UT
Marc W. Buie, Southwest Research Institute