RECON: TNO occultation with 576257

Event between (576257) 12JD68 and star GA0960:05707511 with event index number of 2528784

Geocentric closest approach at 2026/07/09 04:27:49 UTC

J2000 position of star is 17:58:00.1 +06:32:04
Equinox of date position of star is 17:59:04.5 +06:32:01
Stellar brightness G=13.6, use SENSEUP=64 with the MallinCam and and exposure time of 1 seconds with the QHY174 camera.
Star is 117 degrees from the moon. Moon is 35% illuminated.
TNO apparent brightness V=22.8

[RECON map]
TNO is 28.1 AU from the Sun and 27.2 AU from the Earth.
The TNO is moving 22.0 km/sec on the sky relative to the star, or, 4.0 arcsec/hr.
The 1-sigma error in the time of the event is 221 seconds.
The 1-sigma cross-track error in the shadow position is 1646 km.
The sky-plane scale is 19731.0 km/arcsec.

The TNO has an absolute magnitude Hv=8.2
Diameter=138.0 km assuming a 5% albedo -- 6.3 sec chord
Diameter=56.4 km assuming a 30% albedo -- 2.6 sec chord
Dynamical classification is 3:2E+6:4II
 
 
 
 
 
 

Star training set for 576257, (2026/07/09 04:28UT)
Object            RA         Dec     mag  sep  mel
Vega           18:37:50.2 +38:48:34  0.0 33.43  95
60Bet Oph      17:44:47.0 +04:33:29  2.8  4.12 121
PPM 164876     17:58:13.5 +06:29:11  6.5  0.27 117
PPM 164911     17:59:32.3 +06:26:23  9.9  0.11 117
PPM 164898     17:59:07.1 +06:36:45 10.9  0.09 117
576257         17:59:17.6 +06:32:01 13.6       117
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 21.1 km RECON observability=0.2 and success probability=0.1%
Site Site mid-time
(UT)
Sun alt
(deg)
Sky Moon Star alt
(deg)
Star az
(deg)
Target Observing Time
(UT)
X-track
(km)
Kamloops 04:28:57 -2.7 CT Down 36.9 133.8 Up 04:13:57 - 04:43:57 8284
Kelowna 04:28:58 -3.6 CT Down 37.9 134.4 Up 04:13:58 - 04:43:58 8215
Peachland 04:28:58 -3.6 CT Down 37.8 134.0 Up 04:13:58 - 04:43:58 8212
Summerland 04:28:58 -3.7 CT Down 38.0 134.0 Up 04:13:58 - 04:43:58 8200
Penticton 04:28:58 -3.8 CT Down 38.1 134.1 Up 04:13:58 - 04:43:58 8193
Victoria 04:28:58 -2.5 CT Down 36.9 129.3 Up 04:13:58 - 04:43:58 8188
Sleaford 04:28:17 -7.7 NT Down 41.2 151.4 Up 04:13:17 - 04:43:17 8169
Oliver 04:28:58 -4.1 CT Down 38.3 133.9 Up 04:13:58 - 04:43:58 8169
Anarchist Mountain Observatory 04:28:58 -4.3 CT Down 38.5 134.0 Up 04:13:58 - 04:43:58 8154
Tonasket 04:28:58 -4.4 CT Down 38.7 133.8 Up 04:13:58 - 04:43:58 8133
Okanogan 04:28:58 -4.6 CT Down 38.9 133.4 Up 04:13:58 - 04:43:58 8112
Brewster 04:28:58 -4.7 CT Down 39.0 133.0 Up 04:13:58 - 04:43:58 8096
Manson/Chelan 04:28:58 -4.6 CT Down 38.9 132.5 Up 04:13:58 - 04:43:58 8088
Wenatchee 04:28:58 -4.8 CT Down 39.2 132.0 Up 04:13:58 - 04:43:58 8057
Ellensburg 04:28:58 -5.0 CT Down 39.3 131.5 Up 04:13:58 - 04:43:58 8032
Yakima 04:28:58 -5.3 CT Down 39.6 131.2 Up 04:13:58 - 04:43:58 8003
Toppenish/White Swan 04:28:58 -5.5 CT Down 39.8 131.3 Up 04:13:58 - 04:43:58 7985
Goldendale 04:29:13 -5.7 CT Down 40.0 130.5 Up 04:14:13 - 04:44:13 7946
The Dalles 04:29:15 -5.6 CT Down 39.9 130.0 Up 04:14:15 - 04:44:15 7935
PNWRO 04:28:58 -6.5 NT Down 40.8 132.7 Up 04:13:58 - 04:43:58 7931
Maupin 04:29:16 -5.9 CT Down 40.3 129.8 Up 04:14:16 - 04:44:16 7902
Sisters 04:29:19 -6.2 NT Down 40.6 128.7 Up 04:14:19 - 04:44:19 7844
Bend 04:29:20 -6.5 NT Down 40.9 128.9 Up 04:14:20 - 04:44:20 7821
Oregon Observatory 04:29:20 -6.6 NT Down 40.9 128.6 Up 04:14:20 - 04:44:20 7810
North Lake 04:29:21 -7.3 NT Down 41.6 128.8 Up 04:14:21 - 04:44:21 7751
Chiloquin 04:29:26 -7.2 NT Down 41.5 127.3 Up 04:14:26 - 04:44:26 7715
Klamath Falls 04:29:25 -7.5 NT Down 41.7 127.1 Up 04:14:25 - 04:44:25 7687
Lakeview 04:29:22 -8.3 NT Down 42.6 128.6 Up 04:14:22 - 04:44:22 7659
Cedarville 04:29:23 -8.8 NT Down 43.1 128.4 Up 04:14:23 - 04:44:23 7603
Fall River/Burney 04:29:27 -8.4 NT Down 42.7 126.7 Up 04:14:27 - 04:44:27 7586
Susanville 04:29:27 -9.3 NT Down 43.5 127.0 Up 04:14:27 - 04:44:27 7521
Greenville 04:29:29 -9.3 NT Down 43.5 126.5 Up 04:14:29 - 04:44:29 7504
Gimple 04:29:28 -9.3 NT Down 43.5 126.6 Up 04:14:28 - 04:44:28 7502
Quincy 04:29:30 -9.4 NT Down 43.6 126.3 Up 04:14:30 - 04:44:30 7487
Portola 04:29:28 -9.8 NT Down 44.0 126.8 Up 04:14:28 - 04:44:28 7469
Reno 04:29:27 -10.3 NT Down 44.5 127.3 Up 04:14:27 - 04:44:27 7435
Carson City 04:29:28 -10.6 NT Down 44.8 127.0 Up 04:14:28 - 04:44:28 7405
Gardnerville 04:29:28 -10.8 NT Down 44.9 126.9 Up 04:14:28 - 04:44:28 7383
Yerington 04:29:27 -11.1 NT Down 45.3 127.5 Up 04:14:27 - 04:44:27 7377
Hawthorne 04:29:25 -11.7 NT Down 45.9 127.7 Up 04:14:25 - 04:44:25 7328
Lee Vining 04:29:29 -11.8 NT Down 45.9 126.8 Up 04:14:29 - 04:44:29 7289
Tonopah 04:29:22 -12.8 AT Down 47.0 129.0 Up 04:14:22 - 04:44:22 7262
Dunrhomin 04:28:37 -17.5 AT Down 51.7 146.1 Up 04:13:37 - 04:43:37 7231
Bishop 04:29:28 -12.6 AT Down 46.7 127.1 Up 04:14:28 - 04:44:28 7224
Beatty 04:29:24 -13.9 AT Down 48.0 128.5 Up 04:14:24 - 04:44:24 7154
Indian Springs 04:29:22 -14.7 AT Down 48.9 129.5 Up 04:14:22 - 04:44:22 7105
Henderson 04:29:20 -15.5 AT Down 49.7 129.8 Up 04:14:20 - 04:44:20 7045
Patrick 04:29:18 -16.6 AT Down 50.8 130.6 Up 04:14:18 - 04:44:18 6968
Laughlin/Bullhead City 04:29:20 -16.3 AT Down 50.5 129.5 Up 04:14:20 - 04:44:20 6959
Kingman/Dolan Springs 04:29:19 -16.6 AT Down 50.8 130.1 Up 04:14:19 - 04:44:19 6952
Wildwood 04:29:36 -14.7 AT Down 48.5 123.9 Up 04:14:36 - 04:44:36 6941
Mohave Valley 04:29:21 -16.5 AT Down 50.7 129.2 Up 04:14:21 - 04:44:21 6935
Lake Havasu City 04:29:21 -17.0 AT Down 51.1 129.2 Up 04:14:21 - 04:44:21 6894
Idyllwild 04:29:31 -16.1 AT Down 50.0 125.7 Up 04:14:31 - 04:44:31 6873
Parker 04:29:22 -17.2 AT Down 51.3 128.9 Up 04:14:22 - 04:44:22 6862
Calipatria 04:29:29 -17.2 AT Down 51.2 126.4 Up 04:14:29 - 04:44:29 6793
George/Scottsdale 04:29:14 -19.0 Dark Down 53.1 131.4 Up 04:14:14 - 04:44:14 6776
Yuma 04:29:25 -18.0 Dark Down 52.0 127.0 Up 04:14:25 - 04:44:25 6736

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 576257, (2026/07/09 04:28UT)
Object            RA         Dec     mag  sep  mel
Vega           18:36:56.7 +38:47:07  0.0 33.43  95
60Bet Oph      17:43:28.3 +04:34:06  2.8  4.12 121
PPM 164876     17:56:56.0 +06:29:16  6.5  0.27 117
PPM 164911     17:58:14.7 +06:26:26  9.9  0.11 117
PPM 164898     17:57:49.7 +06:36:49 10.9  0.09 117
576257         17:58:00.1 +06:32:04 13.6       117
Positions are for J2000

Event circumstances last updated at 2022/01/15 00:16:19 UT

Marc W. Buie, Southwest Research Institute

RECON