RECON: TNO occultation with 307261

Event between (307261) 02MS4 and star GA0840:16688397 with event index number of 2185194

Geocentric closest approach at 2025/05/19 09:05:24 UTC

J2000 position of star is 19:14:21.4 -05:03:16
Equinox of date position of star is 19:15:32.4 -05:00:53
Stellar brightness G=14.2, use SENSEUP=64 with the MallinCam and and exposure time of 1 seconds with the QHY174 camera.
Star is 32 degrees from the moon. Moon is 62% illuminated.
TNO apparent brightness V=20.5

[RECON map]
TNO is 46.1 AU from the Sun and 45.5 AU from the Earth.
The TNO is moving 15.8 km/sec on the sky relative to the star, or, 1.7 arcsec/hr.
The 1-sigma error in the time of the event is 494 seconds.
The 1-sigma cross-track error in the shadow position is 3874 km.
The sky-plane scale is 32984.9 km/arcsec.

The TNO has an absolute magnitude Hv=3.8
Diameter=1066.6 km assuming a 5% albedo -- 67.5 sec chord
Diameter=435.5 km assuming a 30% albedo -- 27.5 sec chord
Dynamical classification is SCATEXTD
 
 
 
 
 
 

Star training set for 307261, (2025/05/19 09:05UT)
Object            RA         Dec     mag  sep  mel
Antares        16:30:58.1 -26:29:10  0.9 44.77  65
Tarazed        19:47:28.0 +10:40:36  2.7 17.57  37
26 Aql         19:21:54.1 -05:21:59  5.0  1.58  31
PPM 202644     19:13:48.5 -05:22:14  8.3  0.59  33
PPM 202673     19:15:19.1 -04:47:57  9.4  0.23  33
307261         19:15:42.3 -05:00:33 14.2        32
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 1.8 sigma about the mid-time.
The median site spacing is 22.0 km RECON observability=1.0 and success probability=9.3%
Site Site mid-time
(UT)
Sun alt
(deg)
Sky Moon Star alt
(deg)
Star az
(deg)
Target Observing Time
(UT)
X-track
(km)
Sleaford 09:08:34 -12.8 AT Up 30.4 156.7 Up 08:53:34 - 09:23:34 3290
Kamloops 09:09:28 -17.7 AT Up 27.0 141.0 Low 08:54:28 - 09:24:28 2862
Kelowna 09:09:26 -18.3 Dark Up 28.0 141.6 Low 08:54:26 - 09:24:26 2820
Peachland 09:09:28 -18.5 Dark Up 27.9 141.3 Low 08:54:28 - 09:24:28 2804
Summerland 09:09:28 -18.6 Dark Up 28.1 141.3 Low 08:54:28 - 09:24:28 2795
Penticton 09:09:27 -18.7 Dark Up 28.2 141.4 Low 08:54:27 - 09:24:27 2792
Oliver 09:09:28 -19.0 Dark Up 28.4 141.3 Low 08:54:28 - 09:24:28 2765
Anarchist Mountain Observatory 09:09:26 -19.1 Dark Up 28.7 141.4 Low 08:54:26 - 09:24:26 2756
Tonasket 09:09:28 -19.4 Dark Up 28.9 141.3 Low 08:54:28 - 09:24:28 2730
Okanogan 09:09:28 -19.8 Dark Up 29.1 141.0 Low 08:54:28 - 09:24:28 2700
Brewster 09:09:29 -20.1 Dark Up 29.2 140.7 Low 08:54:29 - 09:24:29 2674
Manson/Chelan 09:09:32 -20.3 Dark Up 29.2 140.3 Low 08:54:32 - 09:24:32 2649
Victoria 09:09:41 -20.3 Dark Down 27.3 137.2 Low 08:54:41 - 09:24:41 2624
Wenatchee 09:09:33 -20.8 Dark Up 29.5 139.9 Low 08:54:33 - 09:24:33 2607
Ellensburg 09:09:34 -21.3 Dark Up 29.7 139.5 Low 08:54:34 - 09:24:34 2568
Yakima 09:09:35 -21.7 Dark Up 30.0 139.4 Up 08:54:35 - 09:24:35 2535
PNWRO 09:09:29 -21.8 Dark Up 31.2 140.9 Up 08:54:29 - 09:24:29 2528
Toppenish/White Swan 09:09:34 -21.8 Dark Up 30.3 139.5 Up 08:54:34 - 09:24:34 2521
Goldendale 09:09:37 -22.4 Dark Up 30.5 138.8 Up 08:54:37 - 09:24:37 2466
The Dalles 09:09:39 -22.7 Dark Up 30.5 138.4 Up 08:54:39 - 09:24:39 2438
Dunrhomin 09:08:34 -22.5 Dark Up 41.3 154.0 Up 08:53:34 - 09:23:34 2422
Maupin 09:09:38 -23.1 Dark Up 30.9 138.3 Up 08:54:38 - 09:24:38 2406
CU-SBO 09:08:34 -22.8 Dark Up 41.5 153.8 Up 08:53:34 - 09:23:34 2399
Sisters 09:09:41 -24.0 Dark Up 31.3 137.5 Up 08:54:41 - 09:24:41 2320
Bend 09:09:41 -24.2 Dark Up 31.6 137.6 Up 08:54:41 - 09:24:41 2307
Oregon Observatory 09:09:41 -24.4 Dark Up 31.6 137.4 Up 08:54:41 - 09:24:41 2289
North Lake 09:09:39 -24.9 Dark Up 32.4 137.7 Up 08:54:39 - 09:24:39 2248
Lakeview 09:09:38 -25.8 Dark Up 33.4 137.8 Up 08:54:38 - 09:24:38 2171
Chiloquin 09:09:44 -25.8 Dark Up 32.4 136.5 Up 08:54:44 - 09:24:44 2165
Klamath Falls 09:09:45 -26.1 Dark Up 32.7 136.4 Up 08:54:45 - 09:24:45 2138
Cedarville 09:09:38 -26.4 Dark Up 34.0 137.7 Up 08:54:38 - 09:24:38 2119
Fall River/Burney 09:09:44 -27.1 Dark Up 33.7 136.2 Up 08:54:44 - 09:24:44 2045
Susanville 09:09:42 -27.5 Dark Up 34.6 136.7 Up 08:54:42 - 09:24:42 2009
Gimple 09:09:43 -27.8 Dark Up 34.7 136.4 Up 08:54:43 - 09:24:43 1979
Greenville 09:09:43 -27.9 Dark Up 34.6 136.3 Up 08:54:43 - 09:24:43 1977
Portola 09:09:41 -28.1 Dark Up 35.1 136.6 Up 08:54:41 - 09:24:41 1961
Quincy 09:09:43 -28.0 Dark Up 34.8 136.2 Up 08:54:43 - 09:24:43 1959
Reno 09:09:39 -28.1 Dark Up 35.7 137.1 Up 08:54:39 - 09:24:39 1954
Carson City 09:09:39 -28.5 Dark Up 35.9 137.0 Up 08:54:39 - 09:24:39 1923
Yerington 09:09:37 -28.5 Dark Up 36.4 137.5 Up 08:54:37 - 09:24:37 1923
Gardnerville 09:09:39 -28.7 Dark Up 36.1 136.9 Up 08:54:39 - 09:24:39 1903
Hawthorne 09:09:34 -28.8 Dark Up 37.0 137.9 Up 08:54:34 - 09:24:34 1896
Tonopah 09:09:28 -28.8 Dark Up 38.1 139.1 Up 08:54:28 - 09:24:28 1894
Lee Vining 09:09:37 -29.4 Dark Up 37.2 137.1 Up 08:54:37 - 09:24:37 1832
Indian Springs 09:09:22 -29.7 Dark Up 40.0 140.0 Up 08:54:22 - 09:24:22 1804
Beatty 09:09:27 -29.7 Dark Up 39.2 139.0 Up 08:54:27 - 09:24:27 1803
Bishop 09:09:34 -29.8 Dark Up 38.0 137.5 Up 08:54:34 - 09:24:34 1798
Henderson 09:09:20 -29.9 Dark Up 40.8 140.5 Up 08:54:20 - 09:24:20 1776
Patrick 09:09:15 -30.1 Dark Up 41.8 141.4 Up 08:54:15 - 09:24:15 1752
Kingman/Dolan Springs 09:09:17 -30.4 Dark Up 41.9 141.0 Up 08:54:17 - 09:24:17 1727
Laughlin/Bullhead City 09:09:17 -30.6 Dark Up 41.6 140.4 Up 08:54:17 - 09:24:17 1709
Mohave Valley 09:09:18 -30.8 Dark Up 41.9 140.3 Up 08:54:18 - 09:24:18 1684
George/Scottsdale 09:09:05 -30.9 Dark Up 44.2 142.7 Up 08:54:05 - 09:24:05 1658
Lake Havasu City 09:09:17 -31.1 Dark Up 42.3 140.3 Up 08:54:17 - 09:24:17 1655
Parker 09:09:16 -31.4 Dark Up 42.6 140.2 Up 08:54:16 - 09:24:16 1624
Idyllwild 09:09:27 -32.6 Dark Up 41.6 137.3 Up 08:54:27 - 09:24:27 1515
Calipatria 09:09:22 -32.8 Dark Up 42.7 138.2 Up 08:54:22 - 09:24:22 1493
Wildwood 09:09:36 -32.9 Dark Up 40.3 135.5 Up 08:54:36 - 09:24:36 1492
Yuma 09:09:18 -32.8 Dark Up 43.5 138.9 Up 08:54:18 - 09:24:18 1480

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 307261, (2025/05/19 09:05UT)
Object            RA         Dec     mag  sep  mel
Antares        16:29:24.4 -26:25:56  0.9 44.77  65
Tarazed        19:46:15.6 +10:36:48  2.7 17.57  37
26 Aql         19:20:33.1 -05:24:56  5.0  1.58  31
PPM 202644     19:12:27.4 -05:24:54  8.3  0.59  33
PPM 202673     19:13:58.3 -04:50:39  9.4  0.23  33
307261         19:14:21.4 -05:03:16 14.2        32
Positions are for J2000

Event circumstances last updated at 2022/04/08 04:00:48 UT

Marc W. Buie, Southwest Research Institute

RECON