RECON: TNO occultation with 574398

Event between (574398) 10LO33 and star GA0960:17070102 with event index number of 2519362

Geocentric closest approach at 2026/07/27 04:16:17 UTC

J2000 position of star is 21:39:25.8 +06:02:37
Equinox of date position of star is 21:40:31.8 +06:08:38
Stellar brightness G=14.5, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 56 degrees from the moon. Moon is 94% illuminated.
TNO apparent brightness V=20.6

[RECON map]
TNO is 15.7 AU from the Sun and 14.8 AU from the Earth.
The TNO is moving 18.4 km/sec on the sky relative to the star, or, 6.2 arcsec/hr.
The 1-sigma error in the time of the event is 628 seconds.
The 1-sigma cross-track error in the shadow position is 4777 km.
The sky-plane scale is 10748.5 km/arcsec.

The TNO has an absolute magnitude Hv=8.6
Diameter=116.4 km assuming a 5% albedo -- 6.3 sec chord
Diameter=47.5 km assuming a 30% albedo -- 2.6 sec chord
Dynamical classification is CENTAURR
 
 
 
 
 
 

Star training set for 574398, (2026/07/27 04:16UT)
Object            RA         Dec     mag  sep  mel
Vega           18:37:50.3 +38:48:34  0.0 52.55  66
Markab         23:06:05.2 +15:20:55  2.5 22.86  79
4 Peg          21:39:51.7 +05:53:34  5.9  0.35  56
PPM 172013     21:38:33.6 +05:58:18  8.2  0.58  56
4 Peg          21:39:51.7 +05:53:34  5.9  0.35  56
PPM 172078     21:41:09.3 +06:21:15 10.5  0.21  56
574398         21:40:45.3 +06:09:53 14.5        57
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 1.4 sigma about the mid-time.
The median site spacing is 37.2 km RECON observability=0.2 and success probability=2.2%
Site Site mid-time
(UT)
Sun alt
(deg)
Sky Moon Star alt
(deg)
Star az
(deg)
Target Observing Time
(UT)
X-track
(km)
Kamloops 04:19:17 -4.0 CT Up 13.8 97.4 Really Low 04:04:17 - 04:34:17 6386
Sleaford 04:18:51 -9.5 NT Up 22.2 109.8 Low 04:03:51 - 04:33:51 6329
Kelowna 04:19:21 -5.0 CT Up 14.5 97.9 Really Low 04:04:21 - 04:34:21 6327
Peachland 04:19:21 -4.9 CT Up 14.3 97.7 Really Low 04:04:21 - 04:34:21 6323
Summerland 04:19:22 -5.0 CT Up 14.4 97.7 Really Low 04:04:22 - 04:34:22 6313
Penticton 04:19:22 -5.1 CT Up 14.5 97.8 Really Low 04:04:22 - 04:34:22 6307
Oliver 04:19:24 -5.3 CT Up 14.5 97.7 Really Low 04:04:24 - 04:34:24 6285
Victoria 04:19:30 -3.7 CT Up 12.1 94.6 Really Low 04:04:30 - 04:34:30 6280
Anarchist Mountain Observatory 04:19:24 -5.5 CT Up 14.7 97.8 Really Low 04:04:24 - 04:34:24 6272
Tonasket 04:19:26 -5.7 CT Up 14.7 97.7 Really Low 04:04:26 - 04:34:26 6253
Okanogan 04:19:28 -5.8 CT Up 14.7 97.5 Really Low 04:04:28 - 04:34:28 6232
Brewster 04:19:29 -5.9 CT Up 14.6 97.3 Really Low 04:04:29 - 04:34:29 6217
Manson/Chelan 04:19:31 -5.8 CT Up 14.3 96.9 Really Low 04:04:31 - 04:34:31 6207
Wenatchee 04:19:33 -6.0 NT Up 14.3 96.7 Really Low 04:04:33 - 04:34:33 6177
Ellensburg 04:19:35 -6.2 NT Up 14.2 96.4 Really Low 04:04:35 - 04:34:35 6152
Yakima 04:19:37 -6.4 NT Up 14.2 96.3 Really Low 04:04:37 - 04:34:37 6124
Toppenish/White Swan 04:19:38 -6.6 NT Up 14.4 96.4 Really Low 04:04:38 - 04:34:38 6108
Goldendale 04:19:41 -6.7 NT Up 14.1 95.9 Really Low 04:04:41 - 04:34:41 6075
PNWRO 04:19:38 -7.7 NT Up 15.5 97.4 Really Low 04:04:38 - 04:34:38 6067
The Dalles 04:19:42 -6.7 NT Up 13.9 95.6 Really Low 04:04:42 - 04:34:42 6063
Maupin 04:19:45 -7.0 NT Up 14.0 95.6 Really Low 04:04:45 - 04:34:45 6033
Sisters 04:19:49 -7.2 NT Up 13.8 95.0 Really Low 04:04:49 - 04:34:49 5976
Bend 04:19:50 -7.5 NT Up 14.0 95.2 Really Low 04:04:50 - 04:34:50 5957
Oregon Observatory 04:19:51 -7.5 NT Up 13.9 95.0 Really Low 04:04:51 - 04:34:51 5946
North Lake 04:19:53 -8.2 NT Up 14.4 95.3 Really Low 04:04:53 - 04:34:53 5894
Chiloquin 04:19:57 -8.1 NT Up 13.7 94.4 Really Low 04:04:57 - 04:34:57 5855
Klamath Falls 04:19:58 -8.3 NT Up 13.8 94.4 Really Low 04:04:58 - 04:34:58 5829
Lakeview 04:19:57 -9.2 NT Up 14.9 95.4 Really Low 04:04:57 - 04:34:57 5810
Cedarville 04:20:00 -9.7 NT Up 15.1 95.3 Really Low 04:05:00 - 04:35:00 5759
Fall River/Burney 04:20:04 -9.3 NT Up 14.2 94.4 Really Low 04:05:04 - 04:35:04 5736
Susanville 04:20:06 -10.1 NT Up 14.9 94.7 Really Low 04:05:06 - 04:35:06 5680
Greenville 04:20:07 -10.1 NT Up 14.7 94.5 Really Low 04:05:07 - 04:35:07 5662
Gimple 04:20:07 -10.1 NT Up 14.7 94.5 Really Low 04:05:07 - 04:35:07 5661
Quincy 04:20:08 -10.2 NT Up 14.7 94.4 Really Low 04:05:08 - 04:35:08 5646
Portola 04:20:08 -10.6 NT Up 15.0 94.7 Really Low 04:05:08 - 04:35:08 5631
Reno 04:20:08 -11.1 NT Up 15.6 95.1 Really Low 04:05:08 - 04:35:08 5603
Carson City 04:20:10 -11.4 NT Up 15.6 95.0 Really Low 04:05:10 - 04:35:10 5575
Gardnerville 04:20:11 -11.5 NT Up 15.7 95.0 Really Low 04:05:11 - 04:35:11 5555
Yerington 04:20:10 -11.9 NT Up 16.1 95.3 Really Low 04:05:10 - 04:35:10 5552
Hawthorne 04:20:11 -12.5 AT Up 16.6 95.6 Really Low 04:05:11 - 04:35:11 5509
Dunrhomin 04:19:41 -18.9 Dark Up 26.4 105.5 Low 04:04:41 - 04:34:41 5477
Lee Vining 04:20:14 -12.5 AT Up 16.3 95.1 Really Low 04:05:14 - 04:35:14 5470
Tonopah 04:20:11 -13.7 AT Up 17.7 96.3 Really Low 04:05:11 - 04:35:11 5455
Bishop 04:20:15 -13.4 AT Up 16.9 95.4 Really Low 04:05:15 - 04:35:15 5413
Beatty 04:20:15 -14.7 AT Up 18.2 96.3 Really Low 04:05:15 - 04:35:15 5355
Indian Springs 04:20:15 -15.6 AT Up 19.1 96.8 Really Low 04:05:15 - 04:35:15 5314
Henderson 04:20:16 -16.3 AT Up 19.8 97.1 Really Low 04:05:16 - 04:35:16 5261
Patrick 04:20:17 -17.4 AT Up 20.8 97.5 Low 04:05:17 - 04:35:17 5194
Laughlin/Bullhead City 04:20:19 -17.1 AT Up 20.2 97.0 Low 04:05:19 - 04:35:19 5182
Kingman/Dolan Springs 04:20:18 -17.5 AT Up 20.6 97.3 Low 04:05:18 - 04:35:18 5178
Mohave Valley 04:20:20 -17.3 AT Up 20.3 96.9 Low 04:05:20 - 04:35:20 5159
Wildwood 04:20:29 -15.2 AT Up 17.1 94.3 Really Low 04:05:29 - 04:35:29 5143
Lake Havasu City 04:20:21 -17.7 AT Up 20.5 96.9 Low 04:05:21 - 04:35:21 5122
Parker 04:20:22 -18.0 AT Up 20.6 96.8 Low 04:05:22 - 04:35:22 5091
Idyllwild 04:20:28 -16.7 AT Up 18.6 95.3 Really Low 04:05:28 - 04:35:28 5089
George/Scottsdale 04:20:20 -19.8 Dark Up 22.6 98.1 Low 04:05:20 - 04:35:20 5022
Calipatria 04:20:28 -17.9 AT Up 19.7 95.7 Really Low 04:05:28 - 04:35:28 5020
Yuma 04:20:28 -18.7 Dark Up 20.5 96.1 Low 04:05:28 - 04:35:28 4970

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 574398, (2026/07/27 04:16UT)
Object            RA         Dec     mag  sep  mel
Vega           18:36:56.7 +38:47:07  0.0 52.55  66
Markab         23:04:45.8 +15:12:18  2.5 22.86  79
4 Peg          21:38:32.1 +05:46:19  5.9  0.35  56
PPM 172013     21:37:14.0 +05:51:05  8.2  0.58  56
4 Peg          21:38:32.1 +05:46:19  5.9  0.35  56
PPM 172078     21:39:49.8 +06:13:58 10.5  0.21  56
574398         21:39:25.8 +06:02:37 14.5        56
Positions are for J2000

Event circumstances last updated at 2022/01/15 23:53:32 UT

Marc W. Buie, Southwest Research Institute

RECON