RECON: TNO occultation with 26181

Event between (26181) 96GQ21 and star GA0780:05380898 with event index number of 1390198

Geocentric closest approach at 2025/05/23 04:31:52 UTC

J2000 position of star is 16:37:56.6 -10:43:51
Equinox of date position of star is 16:39:17.6 -10:46:42
Stellar brightness G=14.9, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 117 degrees from the moon. Moon is 21% illuminated.
Apparent brightness V=21.5

[RECON map]
Object is 46.7 AU from the Sun and 45.8 AU from the Earth.
Apparent velocity is 24.3 km/sec on the sky relative to the star, or, 2.6 arcsec/hr.
The 1-sigma error in the time of the event is 89 seconds.
The 1-sigma cross-track error in the shadow position is 1683 km.
The sky-plane scale is 33188.6 km/arcsec.

The object has an absolute magnitude Hv=4.8
Diameter=625.2 km assuming a 5% albedo -- 26.6 sec chord
Diameter=255.2 km assuming a 30% albedo -- 10.9 sec chord
Dynamical classification is SCATNEAR
 
 
 
 
 
 

Star training set for 26181, (2025/05/23 04:31UT)
Object            RA         Dec     mag  sep  mel
Antares        16:30:58.1 -26:29:10  0.9 15.83 117
13Zet Oph      16:38:33.6 -10:37:00  2.6  0.25 117
PPM 199862     16:40:10.7 -08:40:02  6.4  2.12 117
PPM 231966     16:40:22.9 -10:18:47  8.2  0.53 117
PPM 231921     16:38:48.5 -10:47:38  9.6  0.13 117
26181          16:39:20.7 -10:46:48 14.9       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 5.0 sigma about the mid-time.
The median site spacing is 28.5 km RECON observability=0.2 and success probability=0.0%
Site Site mid-time
(UT)
Sun alt
(deg)
Sky Moon Star alt
(deg)
Star az
(deg)
Target Observing Time
(UT)
X-track
(km)
Sleaford 04:34:31 -10.6 NT Down 15.9 133.0 Really Low 04:26:35 - 04:42:26 4994
Kamloops 04:34:56 -5.9 CT Down 9.6 120.3 Really Low 04:27:01 - 04:42:52 4629
Kelowna 04:34:59 -6.9 NT Down 10.5 120.9 Really Low 04:27:03 - 04:42:54 4584
Peachland 04:34:58 -6.8 NT Down 10.4 120.6 Really Low 04:27:03 - 04:42:54 4570
Summerland 04:34:58 -6.9 NT Down 10.5 120.7 Really Low 04:27:03 - 04:42:54 4561
Penticton 04:34:58 -7.0 NT Down 10.6 120.8 Really Low 04:27:02 - 04:42:53 4558
Oliver 04:34:59 -7.3 NT Down 10.8 120.7 Really Low 04:27:03 - 04:42:54 4531
Anarchist Mountain Observatory 04:35:00 -7.5 NT Down 11.0 120.9 Really Low 04:27:04 - 04:42:55 4522
Okanogan 04:35:02 -7.8 NT Down 11.2 120.6 Really Low 04:27:06 - 04:42:57 4467
Brewster 04:35:02 -7.9 NT Down 11.2 120.4 Really Low 04:27:07 - 04:42:58 4443
Manson/Chelan 04:35:03 -7.9 NT Down 11.1 120.0 Really Low 04:27:08 - 04:42:59 4419
Victoria 04:35:07 -5.9 CT Down 8.9 117.5 Really Low 04:27:11 - 04:43:02 4407
Wenatchee 04:35:05 -8.1 NT Down 11.3 119.8 Really Low 04:27:09 - 04:43:00 4378
Ellensburg 04:35:06 -8.3 NT Down 11.3 119.6 Really Low 04:27:10 - 04:43:01 4342
Yakima 04:35:07 -8.6 NT Down 11.5 119.5 Really Low 04:27:12 - 04:43:03 4309
PNWRO 04:35:05 -9.8 NT Down 12.8 120.7 Really Low 04:27:09 - 04:43:00 4295
Toppenish/White Swan 04:35:07 -8.8 NT Down 11.8 119.6 Really Low 04:27:12 - 04:43:03 4295
The Dalles 04:35:09 -8.9 NT Down 11.7 118.8 Really Low 04:27:14 - 04:43:05 4216
Maupin 04:35:11 -9.3 NT Down 11.9 118.8 Really Low 04:27:16 - 04:43:07 4184
Dunrhomin 04:34:49 -20.7 Dark Down 24.3 130.5 Low 04:26:54 - 04:42:45 4124
Nikitin 04:34:51 -20.8 Dark Down 24.4 130.4 Low 04:26:55 - 04:42:46 4108
Sisters 04:35:13 -9.6 NT Down 12.0 118.3 Really Low 04:27:18 - 04:43:09 4102
CU-SBO 04:34:51 -20.8 Dark Down 24.4 130.3 Low 04:26:55 - 04:42:46 4101
Bend 04:35:14 -9.9 NT Down 12.3 118.5 Really Low 04:27:18 - 04:43:09 4087
Oregon Observatory 04:35:14 -10.0 NT Down 12.3 118.3 Really Low 04:27:19 - 04:43:10 4070
Chiloquin 04:35:18 -10.6 NT Down 12.7 117.8 Really Low 04:27:22 - 04:43:13 3950
Klamath Falls 04:35:18 -10.9 NT Down 12.9 117.8 Really Low 04:27:22 - 04:43:13 3923
Cedarville 04:35:17 -12.2 AT Down 14.3 118.8 Really Low 04:27:21 - 04:43:12 3897
Fall River/Burney 04:35:20 -11.9 NT Down 13.7 117.8 Really Low 04:27:25 - 04:43:16 3829
Gimple 04:35:21 -12.8 AT Down 14.5 118.0 Really Low 04:27:25 - 04:43:16 3761
Greenville 04:35:22 -12.7 AT Down 14.4 117.9 Really Low 04:27:26 - 04:43:17 3760
Quincy 04:35:21 -12.9 AT Down 14.5 117.9 Really Low 04:27:26 - 04:43:17 3742
Portola 04:35:21 -13.2 AT Down 14.9 118.2 Really Low 04:27:25 - 04:43:16 3742
Reno 04:35:21 -13.8 AT Down 15.5 118.6 Really Low 04:27:25 - 04:43:16 3732
Carson City 04:35:21 -14.0 AT Down 15.7 118.6 Really Low 04:27:25 - 04:43:16 3701
Yerington 04:35:21 -14.5 AT Down 16.2 119.0 Really Low 04:27:25 - 04:43:16 3698
Gardnerville 04:35:21 -14.2 AT Down 15.8 118.5 Really Low 04:27:25 - 04:43:16 3681
Hawthorne 04:35:20 -15.1 AT Down 16.8 119.3 Really Low 04:27:25 - 04:43:16 3669
Lee Vining 04:35:22 -15.2 AT Down 16.7 118.8 Really Low 04:27:27 - 04:43:18 3608
Bishop 04:35:22 -16.1 AT Down 17.5 119.1 Really Low 04:27:26 - 04:43:17 3571
Beatty 04:35:20 -17.3 AT Down 18.9 120.2 Really Low 04:27:24 - 04:43:15 3567
Patrick 04:35:16 -20.0 Dark Down 21.6 121.9 Low 04:27:21 - 04:43:12 3501
Laughlin/Bullhead City 04:35:18 -19.8 Dark Down 21.3 121.2 Low 04:27:23 - 04:43:14 3461
Lake Havasu City 04:35:18 -20.4 Dark Down 21.8 121.2 Low 04:27:23 - 04:43:14 3406
George/Scottsdale 04:35:14 -22.4 Dark Down 23.9 122.8 Low 04:27:18 - 04:43:09 3396
Idyllwild 04:35:24 -19.6 Dark Down 20.5 119.2 Low 04:27:29 - 04:43:20 3279
Wildwood 04:35:27 -18.2 Dark Down 18.9 118.0 Really Low 04:27:32 - 04:43:23 3267
Calipatria 04:35:23 -20.7 Dark Down 21.6 119.9 Low 04:27:27 - 04:43:18 3251
Yuma 04:35:21 -21.5 Dark Down 22.5 120.4 Low 04:27:26 - 04:43:17 3233

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 26181, (2025/05/23 04:31UT)
Object            RA         Dec     mag  sep  mel
Antares        16:29:24.4 -26:25:56  0.9 15.83 117
13Zet Oph      16:37:09.6 -10:34:01  2.6  0.25 117
PPM 199862     16:38:47.7 -08:37:07  6.4  2.12 117
PPM 231966     16:38:59.0 -10:15:53  8.2  0.53 117
PPM 231921     16:37:24.4 -10:44:40  9.6  0.13 117
26181          16:37:56.6 -10:43:51 14.9       117
Positions are for J2000

Event circumstances last updated at 2024/06/13 03:50:44 UT

Marc W. Buie, Southwest Research Institute

RECON