RECON: TNO occultation with 517717

Event between (517717) 15KZ120 and star GA1320:01848068 with event index number of 2628403

Geocentric closest approach at 2026/10/11 09:09:22 UTC

J2000 position of star is 04:24:15.2 +43:09:16
Equinox of date position of star is 04:25:51.8 +43:12:20
Stellar brightness G=16.3, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 133 degrees from the moon. Moon is 1% illuminated.
TNO apparent brightness V=22.3

[RECON map]
TNO is 15.9 AU from the Sun and 15.4 AU from the Earth.
The TNO is moving 17.9 km/sec on the sky relative to the star, or, 5.8 arcsec/hr.
The 1-sigma error in the time of the event is 77 seconds.
The 1-sigma cross-track error in the shadow position is 5588 km.
The sky-plane scale is 11136.7 km/arcsec.

The TNO has an absolute magnitude Hv=10.1
Diameter=57.5 km assuming a 5% albedo -- 3.1 sec chord
Diameter=23.5 km assuming a 30% albedo -- 1.3 sec chord
Dynamical classification is CENTAURR
 
 
 
 
 
 

Star training set for 517717, (2026/10/11 09:10UT)
Object            RA         Dec     mag  sep  mel
Aldebaran      04:37:27.6 +16:33:40  0.8 26.76 136
3Iot Aur       04:58:44.5 +33:12:21  2.7 11.87 130
PPM 046963     04:19:59.8 +42:12:16  6.1  1.51 135
PPM 047025     04:24:30.7 +43:30:36  7.7  0.42 134
PPM 047040     04:25:54.6 +42:51:55 10.3  0.35 134
517717         04:26:08.3 +43:12:51 16.3       133
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 34.3 km RECON observability=1.0 and success probability=10.7%
Site Site mid-time
(UT)
Sun alt
(deg)
Sky Moon Star alt
(deg)
Star az
(deg)
Target Observing Time
(UT)
X-track
(km)
Kamloops 09:10:49 -43.2 Dark Down 69.1 99.9 Up 09:03:54 - 09:17:44 529
Peachland 09:10:49 -43.8 Dark Down 69.7 98.1 Up 09:03:54 - 09:17:44 449
Manson/Chelan 09:10:49 -45.5 Dark Down 69.6 92.7 Up 09:03:54 - 09:17:44 447
Summerland 09:10:49 -43.9 Dark Down 69.7 97.8 Up 09:03:54 - 09:17:44 438
Kelowna 09:10:49 -43.6 Dark Down 69.8 98.7 Up 09:03:54 - 09:17:44 436
Penticton 09:10:49 -43.9 Dark Down 69.8 97.7 Up 09:03:54 - 09:17:44 428
Brewster 09:10:49 -45.2 Dark Down 69.8 93.6 Up 09:03:54 - 09:17:44 420
Oliver 09:10:49 -44.2 Dark Down 69.9 96.8 Up 09:03:54 - 09:17:44 417
Okanogan 09:10:49 -44.9 Dark Down 69.9 94.5 Up 09:03:54 - 09:17:44 406
Anarchist Mountain Observatory 09:10:49 -44.3 Dark Down 70.0 96.5 Up 09:03:54 - 09:17:44 400
Victoria 09:11:21 -45.9 Dark Down 67.5 91.8 Up 09:04:26 - 09:18:16 327
Sleaford 09:10:12 -36.7 Dark Down 76.8 126.9 Up 09:03:17 - 09:17:07 242
Wenatchee 09:11:14 -45.9 Dark Down 69.5 91.4 Up 09:04:19 - 09:18:09 119
Ellensburg 09:11:16 -46.4 Dark Down 69.4 90.2 Up 09:04:21 - 09:18:11 85
Yakima 09:11:17 -46.7 Dark Down 69.4 89.1 Up 09:04:22 - 09:18:12 45
Toppenish/White Swan 09:11:17 -46.9 Dark Down 69.5 88.6 Up 09:04:22 - 09:18:12 18
The Dalles 09:11:22 -47.8 Dark Down 68.9 86.1 Up 09:04:27 - 09:18:17 -34
Maupin 09:11:22 -48.1 Dark Down 69.0 85.0 Up 09:04:27 - 09:18:17 -80
Sisters 09:11:26 -49.1 Dark Down 68.6 82.5 Up 09:04:31 - 09:18:21 -151
Bend 09:11:26 -49.2 Dark Down 68.7 82.1 Up 09:04:31 - 09:18:21 -183
Oregon Observatory 09:11:27 -49.4 Dark Down 68.6 81.6 Up 09:04:32 - 09:18:22 -196
Chiloquin 09:11:32 -50.6 Dark Down 68.1 78.2 Up 09:04:37 - 09:18:27 -314
Klamath Falls 09:11:33 -50.9 Dark Down 68.1 77.3 Up 09:04:38 - 09:18:28 -351
PNWRO 09:10:49 -46.7 Dark Down 70.5 88.5 Up 09:03:54 - 09:17:44 -432
Cedarville 09:11:28 -50.8 Dark Down 69.1 76.0 Up 09:04:33 - 09:18:23 -477
Fall River/Burney 09:11:34 -51.7 Dark Down 68.1 74.6 Up 09:04:39 - 09:18:29 -483
Greenville 09:11:35 -52.3 Dark Down 68.1 72.5 Up 09:04:40 - 09:18:30 -590
Gimple 09:11:34 -52.3 Dark Down 68.2 72.5 Up 09:04:39 - 09:18:29 -593
Quincy 09:11:35 -52.5 Dark Down 68.1 72.0 Up 09:04:40 - 09:18:30 -610
Portola 09:11:34 -52.4 Dark Down 68.4 71.7 Up 09:04:39 - 09:18:29 -640
Reno 09:11:32 -52.3 Dark Down 68.8 71.1 Up 09:04:37 - 09:18:27 -690
Carson City 09:11:32 -52.6 Dark Down 68.7 70.2 Up 09:04:37 - 09:18:27 -727
Gardnerville 09:11:33 -52.7 Dark Down 68.6 69.6 Up 09:04:38 - 09:18:28 -753
Yerington 09:11:31 -52.4 Dark Down 69.0 69.7 Up 09:04:36 - 09:18:26 -769
Hawthorne 09:11:29 -52.5 Dark Down 69.3 68.5 Up 09:04:34 - 09:18:24 -834
Lee Vining 09:11:33 -53.2 Dark Down 68.7 67.2 Up 09:04:38 - 09:18:28 -875
Bishop 09:11:31 -53.3 Dark Down 69.0 65.7 Up 09:04:36 - 09:18:26 -961
Dunrhomin 09:10:29 -44.0 Dark Down 79.4 69.6 Up 09:03:34 - 09:17:24 -1035
CU-SBO 09:10:29 -44.2 Dark Down 79.3 68.5 Up 09:03:34 - 09:17:24 -1059
Beatty 09:11:25 -52.8 Dark Down 70.0 64.1 Up 09:04:30 - 09:18:20 -1065
Wildwood 09:11:39 -55.9 Dark Down 67.3 58.5 Up 09:04:44 - 09:18:34 -1287
Patrick 09:11:16 -52.2 Dark Down 71.3 58.9 Up 09:04:21 - 09:18:11 -1313
Laughlin/Bullhead City 09:11:19 -52.8 Dark Down 70.7 58.7 Up 09:04:24 - 09:18:14 -1315
Idyllwild 09:11:31 -55.0 Dark Down 68.4 56.8 Up 09:04:36 - 09:18:26 -1391
Lake Havasu City 09:11:19 -53.1 Dark Down 70.5 56.9 Up 09:04:24 - 09:18:14 -1393
Calipatria 09:11:27 -54.7 Dark Down 68.9 54.7 Up 09:04:32 - 09:18:22 -1495
Yuma 09:11:24 -54.5 Dark Down 69.2 53.1 Up 09:04:29 - 09:18:19 -1569
George/Scottsdale 09:10:49 -52.1 Dark Down 71.6 53.2 Up 09:03:54 - 09:17:44 -1597

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 517717, (2026/10/11 09:10UT)
Object            RA         Dec     mag  sep  mel
Aldebaran      04:35:55.3 +16:30:29  0.8 26.76 136
3Iot Aur       04:56:59.6 +33:09:58  2.7 11.87 130
PPM 046963     04:18:08.2 +42:08:27  6.1  1.51 135
PPM 047025     04:22:37.4 +43:26:57  7.7  0.42 134
PPM 047040     04:24:01.8 +42:48:18 10.3  0.35 134
517717         04:24:15.2 +43:09:16 16.3       133
Positions are for J2000

Event circumstances last updated at 2022/11/15 02:46:25 UT

Marc W. Buie, Southwest Research Institute

RECON