RECON: TNO occultation with 12YG12

Event between 12YG12 and star GA1020:02067771 with event index number of 2038042

Geocentric closest approach at 2025/12/28 04:39:48 UTC

J2000 position of star is 06:38:13.8 +13:57:00
Equinox of date position of star is 06:39:29.6 +13:55:44
Stellar brightness G=15.7, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 88 degrees from the moon. Moon is 54% illuminated.
TNO apparent brightness V=22.0

[RECON map]
TNO is 32.9 AU from the Sun and 31.9 AU from the Earth.
The TNO is moving 25.5 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 441 seconds.
The 1-sigma cross-track error in the shadow position is 5878 km.
The sky-plane scale is 23136.5 km/arcsec.

The TNO has an absolute magnitude Hv=6.9
Diameter=253.5 km assuming a 5% albedo -- 9.9 sec chord
Diameter=103.5 km assuming a 30% albedo -- 4.1 sec chord
Dynamical classification is 3:2E
 
 
 
 
 
 

Star training set for 12YG12, (2025/12/28 04:40UT)
Object            RA         Dec     mag  sep  mel
Betelgeuse     05:56:34.8 +07:24:35  0.4 12.43  78
Alhena         06:39:12.8 +16:22:30  1.9  2.45  88
30 Gem         06:45:27.2 +13:11:59  5.8  1.57  90
PPM 122815     06:40:45.2 +13:39:39  8.3  0.37  88
PPM 122800     06:40:10.2 +13:40:56  9.8  0.27  88
PPM 122778     06:39:13.9 +14:02:18 10.9  0.16  88
12YG12         06:39:42.2 +13:55:31 15.7        88
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 2.0 sigma about the mid-time.
The median site spacing is 28.0 km RECON observability=1.0 and success probability=8.6%
Site Site mid-time
(UT)
Sun alt
(deg)
Sky Moon Star alt
(deg)
Star az
(deg)
Target Observing Time
(UT)
X-track
(km)
Sleaford 04:41:49 -50.3 Dark Up 41.3 127.2 Up 04:26:49 - 04:56:49 3784
Kamloops 04:42:20 -42.7 Dark Up 34.2 111.6 Up 04:27:20 - 04:57:20 3708
Kelowna 04:42:20 -43.5 Dark Up 35.0 111.9 Up 04:27:20 - 04:57:20 3628
Peachland 04:42:21 -43.4 Dark Up 34.9 111.6 Up 04:27:21 - 04:57:21 3619
Summerland 04:42:21 -43.5 Dark Up 35.0 111.6 Up 04:27:21 - 04:57:21 3605
Penticton 04:42:21 -43.5 Dark Up 35.1 111.7 Up 04:27:21 - 04:57:21 3598
Oliver 04:42:21 -43.6 Dark Up 35.2 111.4 Up 04:27:21 - 04:57:21 3565
Anarchist Mountain Observatory 04:42:21 -43.8 Dark Up 35.4 111.5 Up 04:27:21 - 04:57:21 3548
Victoria 04:42:30 -41.4 Dark Up 33.0 107.6 Up 04:27:30 - 04:57:30 3530
Tonasket 04:42:22 -43.9 Dark Up 35.4 111.2 Up 04:27:22 - 04:57:22 3520
Okanogan 04:42:23 -43.8 Dark Up 35.5 110.9 Up 04:27:23 - 04:57:23 3489
Brewster 04:42:24 -43.8 Dark Up 35.4 110.5 Up 04:27:24 - 04:57:24 3465
Manson/Chelan 04:42:25 -43.6 Dark Up 35.3 110.0 Up 04:27:25 - 04:57:25 3448
Wenatchee 04:42:26 -43.6 Dark Up 35.3 109.6 Up 04:27:26 - 04:57:26 3404
Ellensburg 04:42:28 -43.6 Dark Up 35.3 109.1 Up 04:27:28 - 04:57:28 3366
Yakima 04:42:28 -43.6 Dark Up 35.5 108.8 Up 04:27:28 - 04:57:28 3328
Toppenish/White Swan 04:42:28 -43.8 Dark Up 35.7 108.8 Up 04:27:28 - 04:57:28 3306
PNWRO 04:42:26 -44.9 Dark Up 36.7 109.9 Up 04:27:26 - 04:57:26 3261
Goldendale 04:42:31 -43.6 Dark Up 35.6 108.1 Up 04:27:31 - 04:57:31 3256
The Dalles 04:42:32 -43.4 Dark Up 35.4 107.6 Up 04:27:32 - 04:57:32 3236
Maupin 04:42:32 -43.6 Dark Up 35.6 107.4 Up 04:27:32 - 04:57:32 3195
Sisters 04:42:35 -43.4 Dark Up 35.5 106.4 Up 04:27:35 - 04:57:35 3114
Bend 04:42:34 -43.6 Dark Up 35.8 106.5 Up 04:27:34 - 04:57:34 3088
Oregon Observatory 04:42:35 -43.5 Dark Up 35.7 106.2 Up 04:27:35 - 04:57:35 3073
North Lake 04:42:35 -44.0 Dark Up 36.3 106.2 Up 04:27:35 - 04:57:35 3006
Chiloquin 04:42:38 -43.4 Dark Up 35.8 105.0 Up 04:27:38 - 04:57:38 2946
Klamath Falls 04:42:39 -43.6 Dark Up 35.9 104.8 Up 04:27:39 - 04:57:39 2911
Lakeview 04:42:36 -44.6 Dark Up 37.0 105.9 Up 04:27:36 - 04:57:36 2897
Cedarville 04:42:36 -44.8 Dark Up 37.3 105.6 Up 04:27:36 - 04:57:36 2830
Fall River/Burney 04:42:40 -44.0 Dark Up 36.5 104.3 Up 04:27:40 - 04:57:40 2791
Susanville 04:42:39 -44.6 Dark Up 37.2 104.4 Up 04:27:39 - 04:57:39 2722
Greenville 04:42:40 -44.4 Dark Up 37.1 104.0 Up 04:27:40 - 04:57:40 2696
Gimple 04:42:40 -44.5 Dark Up 37.1 104.0 Up 04:27:40 - 04:57:40 2695
Quincy 04:42:41 -44.4 Dark Up 37.1 103.8 Up 04:27:41 - 04:57:41 2676
Portola 04:42:40 -44.8 Dark Up 37.5 104.1 Up 04:27:40 - 04:57:40 2659
Dunrhomin 04:42:03 -56.0 Dark Up 48.2 118.2 Up 04:27:03 - 04:57:03 2639
Reno 04:42:39 -45.3 Dark Up 38.0 104.4 Up 04:27:39 - 04:57:39 2628
CU-SBO 04:42:03 -56.0 Dark Up 48.2 117.8 Up 04:27:03 - 04:57:03 2614
Carson City 04:42:39 -45.4 Dark Up 38.2 104.2 Up 04:27:39 - 04:57:39 2591
Yerington 04:42:38 -45.9 Dark Up 38.7 104.5 Up 04:27:38 - 04:57:38 2566
Gardnerville 04:42:40 -45.5 Dark Up 38.2 104.0 Up 04:27:40 - 04:57:40 2566
Hawthorne 04:42:38 -46.4 Dark Up 39.2 104.6 Up 04:27:38 - 04:57:38 2515
Lee Vining 04:42:40 -46.0 Dark Up 39.0 103.8 Up 04:27:40 - 04:57:40 2461
Tonopah 04:42:35 -47.5 Dark Up 40.4 105.3 Up 04:27:35 - 04:57:35 2458
Bishop 04:42:39 -46.7 Dark Up 39.7 103.8 Up 04:27:39 - 04:57:39 2394
Beatty 04:42:36 -48.0 Dark Up 41.0 104.7 Up 04:27:36 - 04:57:36 2335
Indian Springs 04:42:34 -48.9 Dark Up 41.9 105.3 Up 04:27:34 - 04:57:34 2295
Henderson 04:42:33 -49.5 Dark Up 42.6 105.3 Up 04:27:33 - 04:57:33 2235
Patrick 04:42:31 -50.4 Dark Up 43.7 105.6 Up 04:27:31 - 04:57:31 2164
Laughlin/Bullhead City 04:42:33 -49.9 Dark Up 43.2 104.9 Up 04:27:33 - 04:57:33 2141
Kingman/Dolan Springs 04:42:31 -50.3 Dark Up 43.6 105.3 Up 04:27:31 - 04:57:31 2141
Mohave Valley 04:42:33 -49.9 Dark Up 43.2 104.6 Up 04:27:33 - 04:57:33 2113
Lake Havasu City 04:42:33 -50.2 Dark Up 43.5 104.4 Up 04:27:33 - 04:57:33 2069
Wildwood 04:42:44 -46.7 Dark Up 40.2 101.0 Up 04:27:44 - 04:57:44 2054
Parker 04:42:33 -50.2 Dark Up 43.7 104.1 Up 04:27:33 - 04:57:33 2032
Idyllwild 04:42:40 -48.2 Dark Up 41.8 102.0 Up 04:27:40 - 04:57:40 2003
George/Scottsdale 04:42:27 -52.2 Dark Up 45.7 105.6 Up 04:27:27 - 04:57:27 1975
Calipatria 04:42:37 -49.3 Dark Up 42.9 102.3 Up 04:27:37 - 04:57:37 1931
Yuma 04:42:36 -50.0 Dark Up 43.7 102.6 Up 04:27:36 - 04:57:36 1880

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 12YG12, (2025/12/28 04:40UT)
Object            RA         Dec     mag  sep  mel
Betelgeuse     05:55:10.3 +07:24:26  0.4 12.43  78
Alhena         06:37:42.8 +16:23:57  1.9  2.45  88
30 Gem         06:43:59.3 +13:13:40  5.8  1.57  90
PPM 122815     06:39:16.9 +13:41:10  8.3  0.37  88
PPM 122800     06:38:42.0 +13:42:25  9.8  0.27  88
PPM 122778     06:37:45.4 +14:03:45 10.9  0.16  88
12YG12         06:38:13.8 +13:57:00 15.7        88
Positions are for J2000

Event circumstances last updated at 2022/04/12 23:06:50 UT

Marc W. Buie, Southwest Research Institute

RECON