RECON: TNO occultation with 523800

Event between (523800) 17KZ31 and star GA1180:03133496 with event index number of 2432113

Geocentric closest approach at 2026/02/20 05:14:22 UTC

J2000 position of star is 08:12:50.9 +28:08:59
Equinox of date position of star is 08:14:19.8 +28:04:32
Stellar brightness G=13.8, use SENSEUP=64 with the MallinCam and and exposure time of 1 seconds with the QHY174 camera.
Star is 113 degrees from the moon. Moon is 9% illuminated.
Apparent brightness V=23.0

[RECON map]
Object is 18.2 AU from the Sun and 17.3 AU from the Earth.
Apparent velocity is 32.5 km/sec on the sky relative to the star, or, 9.3 arcsec/hr.
The 1-sigma error in the time of the event is 55 seconds.
The 1-sigma cross-track error in the shadow position is 1225 km.
The sky-plane scale is 12580.0 km/arcsec.

The object has an absolute magnitude Hv=10.3
Diameter=52.2 km assuming a 5% albedo -- 1.6 sec chord
Diameter=21.3 km assuming a 30% albedo -- 0.6 sec chord
Dynamical classification is CENTAURR

Star training set for 523800, (2026/02/20 05:14UT)
Object            RA         Dec     mag  sep  mel
Pollux         07:46:54.9 +27:57:39  1.1  6.08 107
15 Cnc         08:14:45.8 +29:34:34  5.6  1.51 113
PPM 098489     08:15:29.1 +27:41:52  8.3  0.44 113
PPM 098479     08:15:07.0 +28:12:41  9.0  0.20 113
523800         08:14:26.9 +28:04:10 13.8       113
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 35.9 km RECON observability=1.0 and success probability=6.4%

Site Site mid-time
(UT) Sun alt
(deg) Sky Moon Star alt
(deg) Star az
(deg) Target Observing Time
(UT) X-track
(km)

Sleaford 05:14:40 -41.9 Dark Down 66.1 179.3 Up 05:09:33 - 05:19:47 4415

Kamloops 05:15:10 -35.9 Dark Down 64.9 148.3 Up 05:10:03 - 05:20:17 4120

Kelowna 05:15:08 -36.8 Dark Down 65.9 149.2 Up 05:10:01 - 05:20:15 4041

Peachland 05:15:09 -36.7 Dark Down 65.9 148.4 Up 05:10:02 - 05:20:16 4028

Summerland 05:15:09 -36.8 Dark Down 66.1 148.5 Up 05:10:02 - 05:20:16 4013

Penticton 05:15:09 -36.9 Dark Down 66.1 148.6 Up 05:10:02 - 05:20:16 4007

Oliver 05:15:09 -37.1 Dark Down 66.4 148.2 Up 05:10:02 - 05:20:16 3970

Anarchist Mountain Observatory 05:15:08 -37.3 Dark Down 66.7 148.4 Up 05:10:01 - 05:20:15 3953

Okanogan 05:15:08 -37.5 Dark Down 67.1 147.1 Up 05:10:01 - 05:20:15 3884

Victoria 05:15:17 -35.2 Dark Down 65.5 139.9 Up 05:10:10 - 05:20:24 3878

Brewster 05:15:09 -37.5 Dark Down 67.3 146.3 Up 05:10:02 - 05:20:16 3854

Manson/Chelan 05:15:10 -37.4 Dark Down 67.3 145.3 Up 05:10:03 - 05:20:17 3830

Wenatchee 05:15:10 -37.6 Dark Down 67.6 144.3 Up 05:10:03 - 05:20:17 3778

Ellensburg 05:15:11 -37.6 Dark Down 67.9 143.2 Up 05:10:04 - 05:20:18 3733

Yakima 05:15:11 -37.8 Dark Down 68.2 142.6 Up 05:10:04 - 05:20:18 3690

Toppenish/White Swan 05:15:10 -38.0 Dark Down 68.4 142.6 Up 05:10:03 - 05:20:17 3668

PNWRO 05:15:07 -39.1 Dark Down 69.3 145.3 Up 05:10:00 - 05:20:14 3640

The Dalles 05:15:12 -37.9 Dark Down 68.7 139.7 Up 05:10:05 - 05:20:19 3580

Maupin 05:15:11 -38.1 Dark Down 69.1 139.2 Up 05:10:04 - 05:20:18 3536

Sisters 05:15:13 -38.2 Dark Down 69.5 136.7 Up 05:10:06 - 05:20:20 3438

Bend 05:15:12 -38.5 Dark Down 69.8 136.8 Up 05:10:05 - 05:20:19 3414

Oregon Observatory 05:15:12 -38.5 Dark Down 69.9 136.2 Up 05:10:05 - 05:20:19 3395

Chiloquin 05:15:14 -38.8 Dark Down 70.6 132.7 Up 05:10:07 - 05:20:21 3250

Klamath Falls 05:15:13 -39.0 Dark Down 70.8 132.1 Up 05:10:06 - 05:20:20 3213

Dunrhomin 05:14:31 -50.5 Dark Down 77.9 181.7 Up 05:09:24 - 05:19:38 3208

Nikitin 05:14:31 -50.6 Dark Down 78.1 181.7 Up 05:09:24 - 05:19:38 3188

CU-SBO 05:14:31 -50.6 Dark Down 78.1 181.3 Up 05:09:24 - 05:19:38 3180

Cedarville 05:15:09 -40.3 Dark Down 72.2 134.1 Up 05:10:02 - 05:20:16 3149

Fall River/Burney 05:15:12 -39.7 Dark Down 71.8 130.3 Up 05:10:05 - 05:20:19 3088

Gimple 05:15:11 -40.4 Dark Down 72.7 129.3 Up 05:10:04 - 05:20:18 2993

Greenville 05:15:11 -40.3 Dark Down 72.7 129.1 Up 05:10:04 - 05:20:18 2992

Quincy 05:15:11 -40.4 Dark Down 72.8 128.6 Up 05:10:04 - 05:20:18 2970

Portola 05:15:10 -40.8 Dark Down 73.2 129.3 Up 05:10:03 - 05:20:17 2960

Reno 05:15:08 -41.4 Dark Down 73.7 130.1 Up 05:10:01 - 05:20:15 2936

Carson City 05:15:08 -41.5 Dark Down 73.9 129.2 Up 05:10:01 - 05:20:15 2897

Yerington 05:15:06 -42.1 Dark Down 74.4 130.2 Up 05:09:59 - 05:20:13 2881

Gardnerville 05:15:07 -41.7 Dark Down 74.1 128.6 Up 05:10:00 - 05:20:14 2871

Hawthorne 05:15:05 -42.6 Dark Down 75.1 130.2 Up 05:09:58 - 05:20:12 2835

Lee Vining 05:15:06 -42.5 Dark Down 75.1 127.3 Up 05:09:59 - 05:20:13 2769

Bishop 05:15:04 -43.2 Dark Down 75.9 127.2 Up 05:09:57 - 05:20:11 2711

Beatty 05:14:59 -44.6 Dark Down 77.2 130.1 Up 05:09:52 - 05:20:06 2676

Patrick 05:14:51 -47.3 Dark Down 79.9 133.9 Up 05:09:44 - 05:19:58 2548

Laughlin/Bullhead City 05:14:53 -46.9 Dark Down 79.7 130.4 Up 05:09:46 - 05:20:00 2512

Lake Havasu City 05:14:52 -47.4 Dark Down 80.3 128.3 Up 05:09:45 - 05:19:59 2442

George/Scottsdale 05:14:45 -49.5 Dark Down 82.3 134.6 Up 05:09:38 - 05:19:52 2391

Wildwood 05:15:03 -44.3 Dark Down 77.5 114.9 Up 05:09:56 - 05:20:10 2350

Idyllwild 05:14:58 -45.9 Dark Down 79.0 117.6 Up 05:09:51 - 05:20:05 2330

Calipatria 05:14:55 -47.0 Dark Down 80.2 117.8 Up 05:09:48 - 05:20:02 2277

Yuma 05:14:52 -47.9 Dark Down 81.0 118.1 Up 05:09:45 - 05:19:59 2241

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 523800, (2026/02/20 05:14UT)
Object            RA         Dec     mag  sep  mel
Pollux         07:45:17.9 +28:01:33  1.1  6.08 107
15 Cnc         08:13:08.9 +29:39:23  5.6  1.51 113
PPM 098489     08:13:53.5 +27:46:42  8.3  0.44 113
PPM 098479     08:13:31.0 +28:17:31  9.0  0.20 113
523800         08:12:50.9 +28:08:59 13.8       113
Positions are for J2000

Event circumstances last updated at 2024/03/19 03:44:31 UT

Marc W. Buie, Southwest Research Institute

RECON

Site	Site mid-time (UT)	Sun alt (deg)	Sky	Moon	Star alt (deg)	Star az (deg)	Target	Observing Time (UT)	X-track (km)
Sleaford	05:14:40	-41.9	Dark	Down	66.1	179.3	Up	05:09:33 - 05:19:47	4415
Kamloops	05:15:10	-35.9	Dark	Down	64.9	148.3	Up	05:10:03 - 05:20:17	4120
Kelowna	05:15:08	-36.8	Dark	Down	65.9	149.2	Up	05:10:01 - 05:20:15	4041
Peachland	05:15:09	-36.7	Dark	Down	65.9	148.4	Up	05:10:02 - 05:20:16	4028
Summerland	05:15:09	-36.8	Dark	Down	66.1	148.5	Up	05:10:02 - 05:20:16	4013
Penticton	05:15:09	-36.9	Dark	Down	66.1	148.6	Up	05:10:02 - 05:20:16	4007
Oliver	05:15:09	-37.1	Dark	Down	66.4	148.2	Up	05:10:02 - 05:20:16	3970
Anarchist Mountain Observatory	05:15:08	-37.3	Dark	Down	66.7	148.4	Up	05:10:01 - 05:20:15	3953
Okanogan	05:15:08	-37.5	Dark	Down	67.1	147.1	Up	05:10:01 - 05:20:15	3884
Victoria	05:15:17	-35.2	Dark	Down	65.5	139.9	Up	05:10:10 - 05:20:24	3878
Brewster	05:15:09	-37.5	Dark	Down	67.3	146.3	Up	05:10:02 - 05:20:16	3854
Manson/Chelan	05:15:10	-37.4	Dark	Down	67.3	145.3	Up	05:10:03 - 05:20:17	3830
Wenatchee	05:15:10	-37.6	Dark	Down	67.6	144.3	Up	05:10:03 - 05:20:17	3778
Ellensburg	05:15:11	-37.6	Dark	Down	67.9	143.2	Up	05:10:04 - 05:20:18	3733
Yakima	05:15:11	-37.8	Dark	Down	68.2	142.6	Up	05:10:04 - 05:20:18	3690
Toppenish/White Swan	05:15:10	-38.0	Dark	Down	68.4	142.6	Up	05:10:03 - 05:20:17	3668
PNWRO	05:15:07	-39.1	Dark	Down	69.3	145.3	Up	05:10:00 - 05:20:14	3640
The Dalles	05:15:12	-37.9	Dark	Down	68.7	139.7	Up	05:10:05 - 05:20:19	3580
Maupin	05:15:11	-38.1	Dark	Down	69.1	139.2	Up	05:10:04 - 05:20:18	3536
Sisters	05:15:13	-38.2	Dark	Down	69.5	136.7	Up	05:10:06 - 05:20:20	3438
Bend	05:15:12	-38.5	Dark	Down	69.8	136.8	Up	05:10:05 - 05:20:19	3414
Oregon Observatory	05:15:12	-38.5	Dark	Down	69.9	136.2	Up	05:10:05 - 05:20:19	3395
Chiloquin	05:15:14	-38.8	Dark	Down	70.6	132.7	Up	05:10:07 - 05:20:21	3250
Klamath Falls	05:15:13	-39.0	Dark	Down	70.8	132.1	Up	05:10:06 - 05:20:20	3213
Dunrhomin	05:14:31	-50.5	Dark	Down	77.9	181.7	Up	05:09:24 - 05:19:38	3208
Nikitin	05:14:31	-50.6	Dark	Down	78.1	181.7	Up	05:09:24 - 05:19:38	3188
CU-SBO	05:14:31	-50.6	Dark	Down	78.1	181.3	Up	05:09:24 - 05:19:38	3180
Cedarville	05:15:09	-40.3	Dark	Down	72.2	134.1	Up	05:10:02 - 05:20:16	3149
Fall River/Burney	05:15:12	-39.7	Dark	Down	71.8	130.3	Up	05:10:05 - 05:20:19	3088
Gimple	05:15:11	-40.4	Dark	Down	72.7	129.3	Up	05:10:04 - 05:20:18	2993
Greenville	05:15:11	-40.3	Dark	Down	72.7	129.1	Up	05:10:04 - 05:20:18	2992
Quincy	05:15:11	-40.4	Dark	Down	72.8	128.6	Up	05:10:04 - 05:20:18	2970
Portola	05:15:10	-40.8	Dark	Down	73.2	129.3	Up	05:10:03 - 05:20:17	2960
Reno	05:15:08	-41.4	Dark	Down	73.7	130.1	Up	05:10:01 - 05:20:15	2936
Carson City	05:15:08	-41.5	Dark	Down	73.9	129.2	Up	05:10:01 - 05:20:15	2897
Yerington	05:15:06	-42.1	Dark	Down	74.4	130.2	Up	05:09:59 - 05:20:13	2881
Gardnerville	05:15:07	-41.7	Dark	Down	74.1	128.6	Up	05:10:00 - 05:20:14	2871
Hawthorne	05:15:05	-42.6	Dark	Down	75.1	130.2	Up	05:09:58 - 05:20:12	2835
Lee Vining	05:15:06	-42.5	Dark	Down	75.1	127.3	Up	05:09:59 - 05:20:13	2769
Bishop	05:15:04	-43.2	Dark	Down	75.9	127.2	Up	05:09:57 - 05:20:11	2711
Beatty	05:14:59	-44.6	Dark	Down	77.2	130.1	Up	05:09:52 - 05:20:06	2676
Patrick	05:14:51	-47.3	Dark	Down	79.9	133.9	Up	05:09:44 - 05:19:58	2548
Laughlin/Bullhead City	05:14:53	-46.9	Dark	Down	79.7	130.4	Up	05:09:46 - 05:20:00	2512
Lake Havasu City	05:14:52	-47.4	Dark	Down	80.3	128.3	Up	05:09:45 - 05:19:59	2442
George/Scottsdale	05:14:45	-49.5	Dark	Down	82.3	134.6	Up	05:09:38 - 05:19:52	2391
Wildwood	05:15:03	-44.3	Dark	Down	77.5	114.9	Up	05:09:56 - 05:20:10	2350
Idyllwild	05:14:58	-45.9	Dark	Down	79.0	117.6	Up	05:09:51 - 05:20:05	2330
Calipatria	05:14:55	-47.0	Dark	Down	80.2	117.8	Up	05:09:48 - 05:20:02	2277
Yuma	05:14:52	-47.9	Dark	Down	81.0	118.1	Up	05:09:45 - 05:19:59	2241