RECON: TNO occultation with 54598

Event between (54598) Bienor and star GA1240:03239738 with event index number of 1477821

Geocentric closest approach at 2025/11/19 11:06:17 UTC

J2000 position of star is 08:18:19.5 +35:03:24
Equinox of date position of star is 08:19:36.7 +34:59:35
Stellar brightness G=15.0, use SENSEUP=128
Star is 110 degrees from the moon. Moon is 1% illuminated.
TNO apparent brightness V=21.5

[RECON map]
TNO is 13.3 AU from the Sun and 12.8 AU from the Earth.
The TNO is moving 7.4 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 222 seconds.
The 1-sigma cross-track error in the shadow position is 1473 km.
The sky-plane scale is 9291.7 km/arcsec.

The TNO has an absolute magnitude Hv=10.0
Diameter=190.6 km assuming a 5% albedo -- 8.1 sec chord
Diameter=77.8 km assuming a 30% albedo -- 3.3 sec chord
Dynamical classification is CENTAURR
 
 
 
 
 
 

Star training set for 54598, (2025/11/19 11:06UT)
Object            RA         Dec     mag  sep  mel
Pollux         07:46:54.0 +27:57:42  1.1  9.94 116
32 Lyn         08:35:01.0 +36:20:48  6.5  3.35 108
PPM 073603     08:21:11.1 +34:57:46  7.6  0.25 110
54598          08:19:59.0 +34:58:28 15.0       110
Positions are for equinox of date

This table contains the target star visibility for the RECON network. The observing range has been set to a maximum of 4.1 sigma about the mid-time.
The median site spacing is 14.6 km RECON observability=1.0 and success probability=16.2%
Site Site mid-time
(UT)
Sun alt
(deg)
Sky Moon Star alt
(deg)
Star az
(deg)
Target Observing Time
(UT)
X-track
(km)
Clarence Fulton 11:11:01 -38.9 Dark Down 70.2 133.6 Up 10:56:01 - 11:26:01 2803
Peachland 11:10:59 -39.3 Dark Down 70.4 131.7 Up 10:55:59 - 11:25:59 2739
Summerland 11:10:57 -39.3 Dark Down 70.5 131.5 Up 10:55:57 - 11:25:57 2730
Penticton 11:10:56 -39.3 Dark Down 70.6 131.6 Up 10:55:56 - 11:25:56 2729
Oliver 11:10:53 -39.4 Dark Down 70.8 130.8 Up 10:55:53 - 11:25:53 2697
Anarchist Mountain Observatory 11:10:50 -39.3 Dark Down 71.0 130.8 Up 10:55:50 - 11:25:50 2690
Niwot 11:07:37 -31.1 Dark Down 84.0 145.9 Up 10:52:37 - 11:22:37 2683
SwRI 11:07:36 -31.1 Dark Down 84.0 144.7 Up 10:52:36 - 11:22:36 2668
Tonasket 11:10:48 -39.4 Dark Down 71.2 130.0 Up 10:55:48 - 11:25:48 2660
Okanogan 11:10:47 -39.6 Dark Down 71.3 128.9 Up 10:55:47 - 11:25:47 2623
Brewster 11:10:45 -39.8 Dark Down 71.4 127.8 Up 10:55:45 - 11:25:45 2590
Manson/Chelan 11:10:47 -40.1 Dark Down 71.3 126.7 Up 10:55:47 - 11:25:47 2555
Entiat 11:10:45 -40.2 Dark Down 71.4 126.0 Up 10:55:45 - 11:25:45 2532
Wenatchee 11:10:43 -40.4 Dark Down 71.5 125.2 Up 10:55:43 - 11:25:43 2504
Victoria 11:11:17 -41.9 Dark Down 69.2 122.5 Up 10:56:17 - 11:26:17 2475
Ellensburg 11:10:42 -40.6 Dark Down 71.6 123.7 Up 10:55:42 - 11:25:42 2457
Pasco 11:10:25 -39.9 Dark Down 72.8 124.4 Up 10:55:25 - 11:25:25 2455
PNWRO 11:10:21 -39.9 Dark Down 73.0 124.2 Up 10:55:21 - 11:25:21 2443
Yakima 11:10:39 -40.8 Dark Down 71.8 122.6 Up 10:55:39 - 11:25:39 2420
Toppenish/White Swan 11:10:36 -40.7 Dark Down 72.0 122.4 Up 10:55:36 - 11:25:36 2408
Goldendale 11:10:35 -41.2 Dark Down 72.0 120.1 Up 10:55:35 - 11:25:35 2339
The Dalles 11:10:38 -41.5 Dark Down 71.9 118.9 Up 10:55:38 - 11:25:38 2302
Maupin 11:10:32 -41.5 Dark Down 72.2 117.9 Up 10:55:32 - 11:25:32 2268
Redmond 11:10:26 -41.8 Dark Down 72.5 115.1 Up 10:55:26 - 11:25:26 2182
Sisters 11:10:29 -42.1 Dark Down 72.2 114.6 Up 10:55:29 - 11:25:29 2166
Bend 11:10:25 -42.0 Dark Down 72.5 114.3 Up 10:55:25 - 11:25:25 2156
Oregon Observatory 11:10:25 -42.1 Dark Down 72.5 113.6 Up 10:55:25 - 11:25:25 2134
La Pine/Gilchrist 11:10:24 -42.2 Dark Down 72.5 112.9 Up 10:55:24 - 11:25:24 2113
North Lake 11:10:13 -41.9 Dark Down 73.1 112.5 Up 10:55:13 - 11:25:13 2101
Paisley 11:10:07 -41.8 Dark Down 73.5 111.3 Up 10:55:07 - 11:25:07 2068
Lakeview 11:10:02 -41.8 Dark Down 73.8 109.9 Up 10:55:02 - 11:25:02 2032
Cedarville 11:09:54 -41.8 Dark Down 74.1 108.0 Up 10:54:54 - 11:24:54 1981
Klamath Falls 11:10:14 -42.8 Dark Down 72.8 108.0 Up 10:55:14 - 11:25:14 1968
Fall River/Burney 11:10:01 -42.8 Dark Down 73.4 104.7 Up 10:55:01 - 11:25:01 1879
Susanville 11:09:49 -42.4 Dark Down 74.1 103.5 Up 10:54:49 - 11:24:49 1858
Tonopah 11:08:58 -40.2 Dark Down 77.0 98.5 Up 10:53:58 - 11:23:58 1824
Gimple 11:09:47 -42.6 Dark Down 74.0 102.3 Up 10:54:47 - 11:24:47 1822
Reno 11:09:34 -41.9 Dark Down 74.8 101.4 Up 10:54:34 - 11:24:34 1821
Greenville 11:09:50 -42.6 Dark Down 73.9 102.2 Up 10:54:50 - 11:24:50 1818
Portola 11:09:41 -42.4 Dark Down 74.3 101.7 Up 10:54:41 - 11:24:41 1812
Yerington 11:09:23 -41.6 Dark Down 75.4 100.1 Up 10:54:23 - 11:24:23 1805
Quincy 11:09:48 -42.7 Dark Down 73.9 101.5 Up 10:54:48 - 11:24:48 1800
DCO 11:07:54 -37.4 Dark Down 80.2 86.8 Up 10:52:54 - 11:22:54 1799
Hawthorne 11:09:14 -41.2 Dark Down 75.8 98.9 Up 10:54:14 - 11:24:14 1791
Carson City 11:09:31 -42.0 Dark Down 74.9 100.2 Up 10:54:31 - 11:24:31 1790
Patrick 11:08:04 -37.9 Dark Down 79.6 88.3 Up 10:53:04 - 11:23:04 1783
Indian Springs 11:08:31 -39.2 Dark Down 78.2 93.1 Up 10:53:31 - 11:23:31 1780
Henderson 11:08:19 -38.8 Dark Down 78.8 91.0 Up 10:53:19 - 11:23:19 1773
Gardnerville 11:09:28 -42.0 Dark Down 75.0 99.3 Up 10:54:28 - 11:24:28 1771
George/Scottsdale 11:07:30 -36.4 Dark Down 81.0 78.4 Up 10:52:30 - 11:22:30 1760
Kingman/Dolan Springs 11:08:03 -38.1 Dark Down 79.5 87.0 Up 10:53:03 - 11:23:03 1754
Beatty 11:08:43 -40.0 Dark Down 77.4 93.8 Up 10:53:43 - 11:23:43 1748
Searchlight/Boulder City 11:08:14 -38.8 Dark Down 78.8 88.1 Up 10:53:14 - 11:23:14 1727
Laughlin/Bullhead City 11:08:08 -38.5 Dark Down 79.1 86.7 Up 10:53:08 - 11:23:08 1722
Lee Vining 11:09:14 -41.7 Dark Down 75.5 96.2 Up 10:54:14 - 11:24:14 1716
Bishop 11:09:02 -41.2 Dark Down 76.1 94.4 Up 10:54:02 - 11:24:02 1701
Mohave Valley 11:08:05 -38.5 Dark Down 79.0 85.3 Up 10:53:05 - 11:23:05 1699
Lake Havasu City 11:07:59 -38.3 Dark Down 79.2 83.3 Up 10:52:59 - 11:22:59 1679
Parker 11:07:56 -38.3 Dark Down 79.1 81.4 Up 10:52:56 - 11:22:56 1651
Blythe 11:07:54 -38.6 Dark Down 78.8 78.8 Up 10:52:54 - 11:22:54 1590
Yuma 11:07:45 -38.7 Dark Down 78.5 74.4 Up 10:52:45 - 11:22:45 1509
Calipatria 11:07:57 -39.4 Dark Down 77.9 76.8 Up 10:52:57 - 11:22:57 1493
Idyllwild 11:08:14 -40.3 Dark Down 77.2 79.7 Up 10:53:14 - 11:23:14 1477
Wildwood 11:08:35 -41.8 Dark Down 75.7 81.2 Up 10:53:35 - 11:23:35 1404
CPSLO 11:09:05 -43.3 Dark Down 74.3 85.3 Up 10:54:05 - 11:24:05 1400

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 54598, (2025/11/19 11:06UT)
Object            RA         Dec     mag  sep  mel
Pollux         07:45:18.0 +28:01:33  1.1  9.94 116
32 Lyn         08:33:21.5 +36:26:11  6.5  3.35 108
PPM 073603     08:19:31.7 +35:02:44  7.6  0.25 110
54598          08:18:19.5 +35:03:24 15.0       110
Positions are for J2000

Event circumstances last updated at 2020/01/30 21:16:24 UT

Marc W. Buie, Southwest Research Institute

RECON