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 11:06:24 UTC

J2000 position of star is 08:18:19.5 +35:03:24
Equinox of date position of star is 08:19:48.8 +34:58:58
Stellar brightness G=15.0, 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 1% illuminated.
Apparent brightness V=18.9

[RECON map]
Object is 13.3 AU from the Sun and 12.8 AU from the Earth.
Apparent velocity is 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 91 seconds.
The 1-sigma cross-track error in the shadow position is 646 km.
The sky-plane scale is 9291.7 km/arcsec.

The object has an absolute magnitude Hv=7.4
Diameter=195.0 km assuming a 5% albedo -- 26.3 sec chord
Diameter=79.6 km assuming a 30% albedo -- 10.7 sec chord
Dynamical classification is CENTAURR
 
 
 
 
 
 

Star training set for 54598, (2025/11/19 11:07UT)
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 5.0 sigma about the mid-time.
The median site spacing is 15.8 km RECON observability=1.0 and success probability=17.0%

Site	Site mid-time (UT)	Sun alt (deg)	Sky	Moon	Star alt (deg)	Star az (deg)	Target	Observing Time (UT)	X-track (km)
Sleaford	11:09:54	-30.5	Dark	Down	72.7	168.1	Up	11:01:51 - 11:17:57	3035
Kamloops	11:11:19	-39.3	Dark	Down	69.5	132.6	Up	11:03:16 - 11:19:22	2262
Kelowna	11:11:07	-39.1	Dark	Down	70.4	132.6	Up	11:03:04 - 11:19:10	2227
Peachland	11:11:08	-39.3	Dark	Down	70.4	131.8	Up	11:03:05 - 11:19:11	2205
Summerland	11:11:06	-39.3	Dark	Down	70.5	131.6	Up	11:03:03 - 11:19:09	2195
Penticton	11:11:05	-39.2	Dark	Down	70.6	131.7	Up	11:03:02 - 11:19:08	2194
Oliver	11:11:02	-39.3	Dark	Down	70.8	130.9	Up	11:02:59 - 11:19:05	2163
Dunrhomin	11:07:47	-31.0	Dark	Down	83.9	147.0	Up	10:59:44 - 11:15:50	2160
Anarchist Mountain Observatory	11:10:59	-39.3	Dark	Down	71.0	130.9	Up	11:02:56 - 11:19:02	2156
Nikitin	11:07:46	-31.1	Dark	Down	84.0	145.8	Up	10:59:43 - 11:15:49	2145
CU-SBO	11:07:45	-31.1	Dark	Down	84.0	144.9	Up	10:59:42 - 11:15:48	2135
Okanogan	11:10:55	-39.6	Dark	Down	71.3	129.0	Up	11:02:52 - 11:18:58	2088
Brewster	11:10:55	-39.8	Dark	Down	71.4	127.9	Up	11:02:52 - 11:18:58	2055
Manson/Chelan	11:10:55	-40.1	Dark	Down	71.3	126.7	Up	11:02:52 - 11:18:58	2020
Wenatchee	11:10:53	-40.4	Dark	Down	71.5	125.2	Up	11:02:50 - 11:18:56	1970
Victoria	11:11:26	-41.9	Dark	Down	69.2	122.5	Up	11:03:23 - 11:19:29	1940
Ellensburg	11:10:52	-40.6	Dark	Down	71.6	123.8	Up	11:02:49 - 11:18:55	1923
PNWRO	11:10:30	-39.8	Dark	Down	73.1	124.2	Up	11:02:27 - 11:18:33	1908
Yakima	11:10:48	-40.8	Dark	Down	71.8	122.7	Up	11:02:45 - 11:18:51	1885
Toppenish/White Swan	11:10:45	-40.7	Dark	Down	72.0	122.4	Up	11:02:42 - 11:18:48	1873
The Dalles	11:10:45	-41.4	Dark	Down	72.0	118.9	Up	11:02:42 - 11:18:48	1767
Maupin	11:10:40	-41.5	Dark	Down	72.2	117.9	Up	11:02:37 - 11:18:43	1734
Sisters	11:10:36	-42.1	Dark	Down	72.3	114.6	Up	11:02:33 - 11:18:39	1631
Bend	11:10:32	-42.0	Dark	Down	72.5	114.3	Up	11:02:29 - 11:18:35	1622
Oregon Observatory	11:10:34	-42.1	Dark	Down	72.5	113.6	Up	11:02:31 - 11:18:37	1600
Chiloquin	11:10:24	-42.7	Dark	Down	72.7	109.0	Up	11:02:21 - 11:18:27	1461
Cedarville	11:10:03	-41.8	Dark	Down	74.1	108.0	Up	11:02:00 - 11:18:06	1447
Klamath Falls	11:10:23	-42.7	Dark	Down	72.8	108.1	Up	11:02:20 - 11:18:26	1433
Fall River/Burney	11:10:08	-42.8	Dark	Down	73.4	104.8	Up	11:02:05 - 11:18:11	1344
Gimple	11:09:57	-42.6	Dark	Down	74.0	102.4	Up	11:01:54 - 11:18:00	1288
Reno	11:09:42	-41.9	Dark	Down	74.8	101.5	Up	11:01:39 - 11:17:45	1287
Greenville	11:09:57	-42.6	Dark	Down	73.9	102.3	Up	11:01:54 - 11:18:00	1284
Portola	11:09:52	-42.3	Dark	Down	74.3	101.7	Up	11:01:49 - 11:17:55	1278
Yerington	11:09:32	-41.5	Dark	Down	75.4	100.2	Up	11:01:29 - 11:17:35	1271
Quincy	11:09:56	-42.7	Dark	Down	74.0	101.6	Up	11:01:53 - 11:17:59	1266
Hawthorne	11:09:23	-41.2	Dark	Down	75.9	98.9	Up	11:01:20 - 11:17:26	1257
Carson City	11:09:39	-42.0	Dark	Down	74.9	100.2	Up	11:01:36 - 11:17:42	1256
Patrick	11:08:13	-37.9	Dark	Down	79.7	88.3	Up	11:00:10 - 11:16:16	1249
Gardnerville	11:09:37	-42.0	Dark	Down	75.0	99.3	Up	11:01:34 - 11:17:40	1236
George/Scottsdale	11:07:39	-36.4	Dark	Down	81.0	78.4	Up	10:59:36 - 11:15:42	1226
Beatty	11:08:52	-40.0	Dark	Down	77.4	93.8	Up	11:00:49 - 11:16:55	1214
Laughlin/Bullhead City	11:08:17	-38.5	Dark	Down	79.1	86.7	Up	11:00:14 - 11:16:20	1188
Lee Vining	11:09:23	-41.7	Dark	Down	75.6	96.2	Up	11:01:20 - 11:17:26	1181
Bishop	11:09:11	-41.2	Dark	Down	76.2	94.5	Up	11:01:08 - 11:17:14	1167
Lake Havasu City	11:08:08	-38.3	Dark	Down	79.2	83.3	Up	11:00:05 - 11:16:11	1145
Yuma	11:07:54	-38.6	Dark	Down	78.6	74.4	Up	10:59:51 - 11:15:57	975
Calipatria	11:08:06	-39.3	Dark	Down	78.0	76.8	Up	11:00:03 - 11:16:09	960
Idyllwild	11:08:23	-40.3	Dark	Down	77.2	79.7	Up	11:00:20 - 11:16:26	943
Wildwood	11:08:44	-41.7	Dark	Down	75.8	81.2	Up	11:00:41 - 11:16:47	870

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 11:07UT)
Object            RA         Dec     mag  sep  mel
Pollux         07:45:17.9 +28:01:33  1.1  9.94 116
32 Lyn         08:33:21.5 +36:26:11  6.5  3.35 108
PPM 073603     08:19:31.6 +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 2023/03/27 03:31:17 UT

RECON