RECON: TNO occultation with 307261

Event between (307261) 02MS4 and star GA0840:16688397 with event index number of 1421444

Geocentric closest approach at 2025/05/19 09:09:03 UTC

J2000 position of star is 19:14:21.4 -05:03:16
Equinox of date position of star is 19:15:23.4 -05:01:11
Stellar brightness G=14.2, use SENSEUP=64
Star is 32 degrees from the moon. Moon is 62% illuminated.
TNO apparent brightness V=20.3

[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 573 seconds.
The 1-sigma cross-track error in the shadow position is 4924 km.
The sky-plane scale is 32984.7 km/arcsec.

The TNO has an absolute magnitude Hv=3.6
Diameter=1148.2 km assuming a 5% albedo -- 72.6 sec chord
Diameter=468.7 km assuming a 30% albedo -- 29.6 sec chord
Dynamical classification is SCATEXTD
 
 
 
 
 
 

Star training set for 307261, (2025/05/19 09:09UT)
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 1.6 sigma about the mid-time.
The median site spacing is 18.8 km RECON observability=1.0 and success probability=7.6%
Site Site mid-time
(UT)
Sun alt
(deg)
Sky Moon Star alt
(deg)
Star az
(deg)
Target Observing Time
(UT)
X-track
(km)
Kelowna 09:13:02 -18.1 Dark Up 28.3 142.7 Low 08:58:02 - 09:28:02 1128
Summerland 09:13:03 -18.4 Dark Up 28.4 142.3 Low 08:58:03 - 09:28:03 1099
Penticton 09:13:03 -18.5 Dark Up 28.5 142.4 Low 08:58:03 - 09:28:03 1096
Okanagan Falls 09:13:04 -18.6 Dark Up 28.7 142.3 Low 08:58:04 - 09:28:04 1081
Oliver 09:13:04 -18.8 Dark Up 28.8 142.2 Low 08:58:04 - 09:28:04 1069
Anarchist Mountain Observatory 09:13:03 -18.9 Dark Up 29.0 142.4 Low 08:58:03 - 09:28:03 1060
Oroville 09:13:04 -19.0 Dark Up 29.1 142.3 Low 08:58:04 - 09:28:04 1052
Tonasket 09:13:04 -19.2 Dark Up 29.2 142.2 Low 08:58:04 - 09:28:04 1034
Okanogan 09:13:05 -19.6 Dark Up 29.4 141.9 Low 08:58:05 - 09:28:05 1005
Brewster 09:13:06 -19.9 Dark Up 29.6 141.6 Low 08:58:06 - 09:28:06 978
Manson/Chelan 09:13:08 -20.1 Dark Up 29.6 141.2 Low 08:58:08 - 09:28:08 953
Entiat 09:13:08 -20.4 Dark Up 29.7 141.0 Low 08:58:08 - 09:28:08 934
Wenatchee 09:13:09 -20.6 Dark Up 29.9 140.9 Low 08:58:09 - 09:28:09 911
Ellensburg 09:13:11 -21.1 Dark Up 30.1 140.5 Up 08:58:11 - 09:28:11 873
Pasco 09:13:06 -21.4 Dark Up 31.3 141.7 Up 08:58:06 - 09:28:06 847
Yakima 09:13:11 -21.5 Dark Up 30.4 140.3 Up 08:58:11 - 09:28:11 840
PNWRO 09:13:05 -21.6 Dark Up 31.6 141.8 Up 08:58:05 - 09:28:05 833
Toppenish/White Swan 09:13:11 -21.6 Dark Up 30.7 140.4 Up 08:58:11 - 09:28:11 826
George/Umatilla 09:13:07 -21.8 Dark Up 31.5 141.3 Up 08:58:07 - 09:28:07 815
Goldendale 09:13:13 -22.2 Dark Up 30.9 139.8 Up 08:58:13 - 09:28:13 771
The Dalles 09:13:14 -22.5 Dark Up 30.9 139.3 Up 08:58:14 - 09:28:14 743
Niwot 09:12:09 -22.3 Dark Up 41.8 155.0 Up 08:57:09 - 09:27:09 718
Maupin 09:13:15 -22.9 Dark Up 31.3 139.2 Up 08:58:15 - 09:28:15 711
SwRI 09:12:10 -22.4 Dark Up 41.8 154.9 Up 08:57:10 - 09:27:10 707
Madras/Culver 09:13:15 -23.4 Dark Up 31.7 139.0 Up 08:58:15 - 09:28:15 665
Redmond 09:13:16 -23.8 Dark Up 31.9 138.8 Up 08:58:16 - 09:28:16 633
Sisters 09:13:17 -23.8 Dark Up 31.7 138.4 Up 08:58:17 - 09:28:17 625
Bend 09:13:17 -24.0 Dark Up 32.0 138.6 Up 08:58:17 - 09:28:17 612
Oregon Observatory 09:13:18 -24.2 Dark Up 32.1 138.4 Up 08:58:18 - 09:28:18 594
La Pine/Gilchrist 09:13:18 -24.4 Dark Up 32.2 138.2 Up 08:58:18 - 09:28:18 575
North Lake 09:13:16 -24.7 Dark Up 32.8 138.6 Up 08:58:16 - 09:28:16 554
Paisley 09:13:15 -25.1 Dark Up 33.4 138.8 Up 08:58:15 - 09:28:15 516
Lakeview 09:13:15 -25.6 Dark Up 33.9 138.8 Up 08:58:15 - 09:28:15 477
Chiloquin 09:13:20 -25.6 Dark Up 32.9 137.4 Up 08:58:20 - 09:28:20 471
Klamath Falls 09:13:20 -25.9 Dark Up 33.2 137.3 Up 08:58:20 - 09:28:20 444
Tulelake 09:13:20 -26.0 Dark Up 33.5 137.5 Up 08:58:20 - 09:28:20 428
Cedarville 09:13:15 -26.1 Dark Up 34.5 138.6 Up 08:58:15 - 09:28:15 425
Fall River/Burney 09:13:20 -26.9 Dark Up 34.2 137.2 Up 08:58:20 - 09:28:20 351
Susanville 09:13:17 -27.3 Dark Up 35.1 137.6 Up 08:58:17 - 09:28:17 316
Gimple 09:13:19 -27.6 Dark Up 35.2 137.3 Up 08:58:19 - 09:28:19 285
Greenville 09:13:19 -27.6 Dark Up 35.1 137.2 Up 08:58:19 - 09:28:19 283
Portola 09:13:17 -27.8 Dark Up 35.6 137.5 Up 08:58:17 - 09:28:17 267
Quincy 09:13:19 -27.8 Dark Up 35.3 137.1 Up 08:58:19 - 09:28:19 266
Reno 09:13:15 -27.9 Dark Up 36.1 138.1 Up 08:58:15 - 09:28:15 261
Yerington 09:13:12 -28.2 Dark Up 36.9 138.5 Up 08:58:12 - 09:28:12 230
Carson City 09:13:15 -28.2 Dark Up 36.4 137.9 Up 08:58:15 - 09:28:15 230
Gardnerville 09:13:15 -28.4 Dark Up 36.6 137.9 Up 08:58:15 - 09:28:15 210
Hawthorne 09:13:10 -28.5 Dark Up 37.5 138.8 Up 08:58:10 - 09:28:10 204
Tonopah 09:13:05 -28.5 Dark Up 38.6 140.1 Up 08:58:05 - 09:28:05 202
Lee Vining 09:13:13 -29.2 Dark Up 37.7 138.0 Up 08:58:13 - 09:28:13 140
Indian Springs 09:12:58 -29.4 Dark Up 40.5 141.0 Up 08:57:58 - 09:27:58 113
Beatty 09:13:03 -29.4 Dark Up 39.7 140.0 Up 08:58:03 - 09:28:03 111
Bishop 09:13:10 -29.5 Dark Up 38.5 138.5 Up 08:58:10 - 09:28:10 107
Henderson 09:12:55 -29.6 Dark Up 41.2 141.5 Up 08:57:55 - 09:27:55 85
Patrick 09:12:50 -29.8 Dark Up 42.3 142.4 Up 08:57:50 - 09:27:50 62
DCO 09:12:46 -29.8 Dark Up 42.9 143.1 Up 08:57:46 - 09:27:46 55
Lone Pine 09:13:09 -30.1 Dark Up 39.2 138.4 Up 08:58:09 - 09:28:09 47
Kingman/Dolan Springs 09:12:51 -30.0 Dark Up 42.4 142.1 Up 08:57:51 - 09:27:51 36
Searchlight/Boulder City 09:12:55 -30.1 Dark Up 41.7 141.2 Up 08:57:55 - 09:27:55 35
Laughlin/Bullhead City 09:12:53 -30.3 Dark Up 42.1 141.5 Up 08:57:53 - 09:27:53 19
Mohave Valley 09:12:53 -30.5 Dark Up 42.3 141.3 Up 08:57:53 - 09:27:53 -6
Lake Havasu City 09:12:52 -30.8 Dark Up 42.8 141.4 Up 08:57:52 - 09:27:52 -35
Parker 09:12:52 -31.1 Dark Up 43.1 141.2 Up 08:57:52 - 09:27:52 -66
Blythe 09:12:53 -31.6 Dark Up 43.3 140.5 Up 08:57:53 - 09:27:53 -123
CPSLO 09:13:21 -32.1 Dark Up 38.8 135.0 Up 08:58:21 - 09:28:21 -146
Idyllwild 09:13:03 -32.3 Dark Up 42.1 138.2 Up 08:58:03 - 09:28:03 -176
Calipatria 09:12:58 -32.4 Dark Up 43.2 139.2 Up 08:57:58 - 09:27:58 -197
Wildwood 09:13:12 -32.6 Dark Up 40.8 136.4 Up 08:58:12 - 09:28:12 -198
Yuma 09:12:53 -32.5 Dark Up 44.0 139.9 Up 08:57:53 - 09:27:53 -210

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 09:09UT)
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 2019/06/08 11:27:36 UT

Marc W. Buie, Southwest Research Institute

RECON