RECON: TNO occultation with 55638

Event between (55638) 02VE95 and star GA0960:02306197 with event index number of 2249836

Geocentric closest approach at 2023/12/31 04:42:27 UTC

J2000 position of star is 06:52:56.0 +06:03:12
Equinox of date position of star is 06:54:12.8 +06:01:21
Stellar brightness G=11.9, use SENSEUP=8 with the MallinCam and and exposure time of 125 milli-seconds with the QHY174 camera.
Star is 47 degrees from the moon. Moon is 84% illuminated.
Apparent brightness V=20.5

[RECON map]
Object is 31.2 AU from the Sun and 30.2 AU from the Earth.
Apparent velocity is 24.4 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 98 seconds.
The 1-sigma cross-track error in the shadow position is 1210 km.
The sky-plane scale is 21916.2 km/arcsec.

The object has an absolute magnitude Hv=5.6
Diameter=524.8 km assuming a 5% albedo -- 18.8 sec chord
Diameter=214.3 km assuming a 30% albedo -- 7.7 sec chord
Dynamical classification is 3:2E
 
 
 
 
 
 

Star training set for 55638, (2023/12/31 04:42UT)
Object            RA         Dec     mag  sep  mel
Betelgeuse     05:56:28.3 +07:24:34  0.4 14.40  60
Alhena         06:39:05.9 +16:22:36  1.9 11.00  48
PPM 151677     07:00:37.9 +07:16:56  6.1  2.03  45
PPM 151373     06:52:16.4 +05:48:44  7.4  0.53  48
PPM 151447     06:54:11.9 +05:51:47  9.3  0.16  47
55638          06:54:13.1 +06:01:21 11.9        47
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 28.7 km RECON observability=1.0 and success probability=0.3%
Site Site mid-time
(UT)
Sun alt
(deg)
Sky Moon Star alt
(deg)
Star az
(deg)
Target Observing Time
(UT)
X-track
(km)
Sleaford 04:44:20 -50.3 Dark Up 34.1 131.4 Up 04:35:40 - 04:53:00 -2008
Kamloops 04:44:51 -42.8 Dark Up 27.4 116.5 Low 04:36:11 - 04:53:31 -2086
Kelowna 04:44:52 -43.6 Dark Up 28.3 116.9 Low 04:36:12 - 04:53:32 -2155
Peachland 04:44:53 -43.5 Dark Up 28.2 116.6 Low 04:36:13 - 04:53:33 -2162
Summerland 04:44:53 -43.6 Dark Up 28.3 116.6 Low 04:36:13 - 04:53:33 -2175
Penticton 04:44:53 -43.6 Dark Up 28.4 116.7 Low 04:36:13 - 04:53:33 -2181
Oliver 04:44:54 -43.7 Dark Up 28.6 116.5 Low 04:36:14 - 04:53:34 -2209
Anarchist Mountain Observatory 04:44:54 -43.9 Dark Up 28.8 116.6 Low 04:36:14 - 04:53:34 -2224
Victoria 04:45:02 -41.5 Dark Up 26.6 112.8 Low 04:36:22 - 04:53:42 -2250
Okanogan 04:44:56 -44.0 Dark Up 28.9 116.1 Low 04:36:16 - 04:53:36 -2276
Brewster 04:44:57 -43.9 Dark Up 28.9 115.8 Low 04:36:17 - 04:53:37 -2298
Manson/Chelan 04:44:58 -43.7 Dark Up 28.8 115.4 Low 04:36:18 - 04:53:38 -2314
Wenatchee 04:45:00 -43.7 Dark Up 28.9 115.0 Low 04:36:20 - 04:53:40 -2353
Ellensburg 04:45:01 -43.7 Dark Up 28.9 114.6 Low 04:36:21 - 04:53:41 -2387
Yakima 04:45:02 -43.8 Dark Up 29.1 114.4 Low 04:36:22 - 04:53:42 -2422
Toppenish/White Swan 04:45:02 -43.9 Dark Up 29.3 114.4 Low 04:36:22 - 04:53:42 -2441
PNWRO 04:45:00 -45.0 Dark Up 30.4 115.5 Up 04:36:20 - 04:53:40 -2477
The Dalles 04:45:06 -43.6 Dark Up 29.1 113.3 Low 04:36:26 - 04:53:46 -2504
Maupin 04:45:06 -43.7 Dark Up 29.3 113.2 Low 04:36:26 - 04:53:46 -2541
Sisters 04:45:10 -43.5 Dark Up 29.4 112.3 Low 04:36:30 - 04:53:50 -2615
Bend 04:45:09 -43.8 Dark Up 29.6 112.4 Low 04:36:29 - 04:53:49 -2637
Oregon Observatory 04:45:10 -43.7 Dark Up 29.6 112.2 Low 04:36:30 - 04:53:50 -2652
Chiloquin 04:45:14 -43.6 Dark Up 29.8 111.2 Low 04:36:34 - 04:53:54 -2767
Klamath Falls 04:45:15 -43.7 Dark Up 30.0 111.1 Up 04:36:35 - 04:53:55 -2798
Cedarville 04:45:12 -45.0 Dark Up 31.4 112.0 Up 04:36:32 - 04:53:52 -2867
Fall River/Burney 04:45:16 -44.2 Dark Up 30.7 110.8 Up 04:36:36 - 04:53:56 -2907
Greenville 04:45:17 -44.6 Dark Up 31.3 110.6 Up 04:36:37 - 04:53:57 -2992
Gimple 04:45:17 -44.7 Dark Up 31.4 110.7 Up 04:36:37 - 04:53:57 -2992
Quincy 04:45:18 -44.6 Dark Up 31.4 110.5 Up 04:36:38 - 04:53:58 -3010
Portola 04:45:17 -45.0 Dark Up 31.8 110.8 Up 04:36:37 - 04:53:57 -3024
Dunrhomin 04:44:39 -56.2 Dark Up 41.9 125.0 Up 04:35:59 - 04:53:19 -3025
Nikitin 04:44:40 -56.2 Dark Up 41.9 124.8 Up 04:36:00 - 04:53:20 -3042
CU-SBO 04:44:40 -56.2 Dark Up 41.9 124.7 Up 04:36:00 - 04:53:20 -3047
Reno 04:45:16 -45.5 Dark Up 32.4 111.2 Up 04:36:36 - 04:53:56 -3051
Carson City 04:45:17 -45.6 Dark Up 32.5 111.0 Up 04:36:37 - 04:53:57 -3085
Yerington 04:45:16 -46.1 Dark Up 33.0 111.4 Up 04:36:36 - 04:53:56 -3105
Gardnerville 04:45:17 -45.7 Dark Up 32.6 110.9 Up 04:36:37 - 04:53:57 -3108
Hawthorne 04:45:15 -46.6 Dark Up 33.6 111.5 Up 04:36:35 - 04:53:55 -3151
Lee Vining 04:45:18 -46.2 Dark Up 33.4 110.8 Up 04:36:38 - 04:53:58 -3202
Bishop 04:45:17 -46.9 Dark Up 34.2 111.0 Up 04:36:37 - 04:53:57 -3262
Beatty 04:45:14 -48.2 Dark Up 35.6 112.0 Up 04:36:34 - 04:53:54 -3312
Patrick 04:45:10 -50.7 Dark Up 38.3 113.4 Up 04:36:30 - 04:53:50 -3466
Laughlin/Bullhead City 04:45:12 -50.1 Dark Up 37.9 112.6 Up 04:36:32 - 04:53:52 -3488
Lake Havasu City 04:45:13 -50.4 Dark Up 38.3 112.3 Up 04:36:33 - 04:53:53 -3554
Wildwood 04:45:24 -46.9 Dark Up 35.2 108.7 Up 04:36:44 - 04:54:04 -3578
Idyllwild 04:45:20 -48.5 Dark Up 36.8 109.9 Up 04:36:40 - 04:54:00 -3620
George/Scottsdale 04:45:07 -52.5 Dark Up 40.5 113.8 Up 04:36:27 - 04:53:47 -3638
Calipatria 04:45:18 -49.5 Dark Up 37.9 110.4 Up 04:36:38 - 04:53:58 -3685
Yuma 04:45:17 -50.3 Dark Up 38.7 110.7 Up 04:36:37 - 04:53:57 -3731

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 55638, (2023/12/31 04:42UT)
Object            RA         Dec     mag  sep  mel
Betelgeuse     05:55:10.3 +07:24:26  0.4 14.40  60
Alhena         06:37:42.8 +16:23:57  1.9 11.00  48
PPM 151677     06:59:20.1 +07:19:00  6.1  2.03  45
PPM 151373     06:50:59.5 +05:50:32  7.4  0.53  48
PPM 151447     06:52:54.9 +05:53:38  9.3  0.16  47
55638          06:52:56.0 +06:03:12 11.9        47
Positions are for J2000

Event circumstances last updated at 2023/12/06 05:55:58 UT

Marc W. Buie, Southwest Research Institute

RECON