RECON: TNO occultation with 181855

Event between (181855) 98WT31 and star GA1320:02848007 with event index number of 1300448

Geocentric closest approach at 2024/01/09 05:44:15 UTC

J2000 position of star is 05:17:47.2 +43:19:55
Equinox of date position of star is 05:19:23.1 +43:21:15
Stellar brightness G=15.1, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 164 degrees from the moon. Moon is 7% illuminated.
TNO apparent brightness V=23.5

[RECON map]
TNO is 37.6 AU from the Sun and 36.8 AU from the Earth.
The TNO is moving 22.4 km/sec on the sky relative to the star, or, 3.0 arcsec/hr.
The 1-sigma error in the time of the event is 294 seconds.
The 1-sigma cross-track error in the shadow position is 3645 km.
The sky-plane scale is 26671.4 km/arcsec.

The TNO has an absolute magnitude Hv=7.7
Diameter=173.8 km assuming a 5% albedo -- 7.8 sec chord
Diameter=70.9 km assuming a 30% albedo -- 3.2 sec chord
Dynamical classification is SCATEXTD
 
 
 
 
 
 

Star training set for 181855, (2024/01/09 05:44UT)
Object            RA         Dec     mag  sep  mel
Aldebaran      04:37:18.1 +16:33:21  0.8 28.26 167
34Bet Aur      06:01:17.5 +44:56:50  1.9  7.66 159
20Rho Aur      05:23:30.6 +41:49:33  4.9  1.70 165
PPM 047955     05:19:58.9 +42:48:55  7.0  0.55 164
PPM 047931     05:18:50.4 +43:27:07  9.8  0.16 164
181855         05:19:30.8 +43:21:21 15.1       164
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 3.1 sigma about the mid-time.
The median site spacing is 31.1 km RECON observability=1.0 and success probability=14.9%
Site Site mid-time
(UT)
Sun alt
(deg)
Sky Moon Star alt
(deg)
Star az
(deg)
Target Observing Time
(UT)
X-track
(km)
Kamloops 05:44:25 -50.1 Dark Down 81.8 151.2 Up 05:29:25 - 05:59:25 -681
Sleaford 05:43:41 -55.7 Dark Down 79.4 217.5 Up 05:28:41 - 05:58:41 -705
Kelowna 05:44:24 -51.0 Dark Down 82.8 152.8 Up 05:29:24 - 05:59:24 -784
Peachland 05:44:25 -50.9 Dark Down 82.8 150.8 Up 05:29:25 - 05:59:25 -790
Summerland 05:44:25 -51.0 Dark Down 82.9 150.7 Up 05:29:25 - 05:59:25 -808
Penticton 05:44:25 -51.1 Dark Down 83.0 151.1 Up 05:29:25 - 05:59:25 -817
Victoria 05:44:38 -49.4 Dark Down 82.2 128.4 Up 05:29:38 - 05:59:38 -848
Oliver 05:44:25 -51.3 Dark Down 83.3 149.6 Up 05:29:25 - 05:59:25 -855
Anarchist Mountain Observatory 05:44:25 -51.5 Dark Down 83.5 150.0 Up 05:29:25 - 05:59:25 -876
Tonasket 05:44:25 -51.6 Dark Down 83.8 148.1 Up 05:29:25 - 05:59:25 -908
Okanogan 05:44:27 -51.7 Dark Down 84.0 145.6 Up 05:29:27 - 05:59:27 -941
Brewster 05:44:27 -51.7 Dark Down 84.2 142.8 Up 05:29:27 - 05:59:27 -967
Manson/Chelan 05:44:29 -51.6 Dark Down 84.2 139.4 Up 05:29:29 - 05:59:29 -982
Wenatchee 05:44:30 -51.8 Dark Down 84.4 135.3 Up 05:29:30 - 05:59:30 -1030
Ellensburg 05:44:31 -51.8 Dark Down 84.6 130.9 Up 05:29:31 - 05:59:31 -1070
Yakima 05:44:32 -52.0 Dark Down 84.9 127.4 Up 05:29:32 - 05:59:32 -1113
Toppenish/White Swan 05:44:31 -52.2 Dark Down 85.1 126.3 Up 05:29:31 - 05:59:31 -1139
Goldendale 05:44:33 -52.2 Dark Down 85.1 118.7 Up 05:29:33 - 05:59:33 -1190
The Dalles 05:44:35 -52.1 Dark Down 85.0 114.8 Up 05:29:35 - 05:59:35 -1206
PNWRO 05:44:27 -53.3 Dark Down 86.1 132.1 Up 05:29:27 - 05:59:27 -1208
Maupin 05:44:35 -52.3 Dark Down 85.3 110.7 Up 05:29:35 - 05:59:35 -1253
Sisters 05:44:38 -52.4 Dark Down 85.1 99.2 Up 05:29:38 - 05:59:38 -1337
Bend 05:44:37 -52.6 Dark Down 85.4 96.8 Up 05:29:37 - 05:59:37 -1368
Oregon Observatory 05:44:38 -52.6 Dark Down 85.3 94.5 Up 05:29:38 - 05:59:38 -1384
North Lake 05:44:37 -53.2 Dark Down 85.7 86.8 Up 05:29:37 - 05:59:37 -1464
Chiloquin 05:44:42 -52.9 Dark Down 84.9 79.0 Up 05:29:42 - 05:59:42 -1516
Klamath Falls 05:44:41 -53.0 Dark Down 84.9 75.2 Up 05:29:41 - 05:59:41 -1554
Lakeview 05:44:37 -54.0 Dark Down 85.9 72.0 Up 05:29:37 - 05:59:37 -1590
Cedarville 05:44:36 -54.4 Dark Down 85.8 63.1 Up 05:29:36 - 05:59:36 -1664
Fall River/Burney 05:44:41 -53.7 Dark Down 84.7 62.1 Up 05:29:41 - 05:59:41 -1689
Susanville 05:44:40 -54.5 Dark Down 84.9 53.5 Up 05:29:40 - 05:59:40 -1773
Greenville 05:44:42 -54.3 Dark Down 84.5 52.3 Up 05:29:42 - 05:59:42 -1796
Gimple 05:44:41 -54.4 Dark Down 84.6 52.0 Up 05:29:41 - 05:59:41 -1798
Quincy 05:44:41 -54.4 Dark Down 84.4 50.7 Up 05:29:41 - 05:59:41 -1818
Portola 05:44:40 -54.8 Dark Down 84.6 47.5 Up 05:29:40 - 05:59:40 -1842
Reno 05:44:38 -55.4 Dark Down 84.8 42.2 Up 05:29:38 - 05:59:38 -1885
Carson City 05:44:38 -55.5 Dark Down 84.5 39.5 Up 05:29:38 - 05:59:38 -1924
Gardnerville 05:44:38 -55.6 Dark Down 84.3 37.7 Up 05:29:38 - 05:59:38 -1951
Yerington 05:44:36 -56.0 Dark Down 84.6 34.6 Up 05:29:36 - 05:59:36 -1958
Dunrhomin 05:43:43 -64.7 Dark Down 82.2 296.4 Up 05:28:43 - 05:58:43 -2017
Hawthorne 05:44:35 -56.6 Dark Down 84.5 28.7 Up 05:29:35 - 05:59:35 -2019
CU-SBO 05:43:44 -64.8 Dark Down 82.2 298.2 Up 05:28:44 - 05:58:44 -2044
Lee Vining 05:44:37 -56.4 Dark Down 83.8 29.0 Up 05:29:37 - 05:59:37 -2070
Tonopah 05:44:30 -57.7 Dark Down 84.5 17.3 Up 05:29:30 - 05:59:30 -2098
Bishop 05:44:35 -57.1 Dark Down 83.5 22.5 Up 05:29:35 - 05:59:35 -2149
Beatty 05:44:29 -58.5 Dark Down 83.4 11.6 Up 05:29:29 - 05:59:29 -2232
Indian Springs 05:44:26 -59.4 Dark Down 83.2 4.6 Up 05:29:26 - 05:59:26 -2287
Henderson 05:44:23 -60.1 Dark Down 82.7 0.3 Up 05:29:23 - 05:59:23 -2357
Patrick 05:44:20 -61.1 Dark Down 82.0 354.5 Up 05:29:20 - 05:59:20 -2444
Laughlin/Bullhead City 05:44:22 -60.7 Dark Down 81.8 358.2 Up 05:29:22 - 05:59:22 -2458
Kingman/Dolan Springs 05:44:20 -61.1 Dark Down 81.8 355.6 Up 05:29:20 - 05:59:20 -2465
Mohave Valley 05:44:23 -60.8 Dark Down 81.6 358.2 Up 05:29:23 - 05:59:23 -2488
Wildwood 05:44:40 -57.8 Dark Down 80.3 15.8 Up 05:29:40 - 05:59:40 -2495
Lake Havasu City 05:44:22 -61.1 Dark Down 81.2 357.2 Up 05:29:22 - 05:59:22 -2535
Idyllwild 05:44:33 -59.4 Dark Down 80.3 7.6 Up 05:29:33 - 05:59:33 -2573
Parker 05:44:23 -61.2 Dark Down 80.8 357.1 Up 05:29:23 - 05:59:23 -2574
George/Scottsdale 05:44:13 -63.2 Dark Down 80.1 347.1 Up 05:29:13 - 05:59:13 -2659
Calipatria 05:44:28 -60.5 Dark Down 79.8 2.4 Up 05:29:28 - 05:59:28 -2660
Yuma 05:44:25 -61.3 Dark Down 79.4 358.8 Up 05:29:25 - 05:59:25 -2723

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 181855, (2024/01/09 05:44UT)
Object            RA         Dec     mag  sep  mel
Aldebaran      04:35:55.3 +16:30:29  0.8 28.26 167
34Bet Aur      05:59:31.6 +44:56:51  1.9  7.66 159
20Rho Aur      05:21:48.4 +41:48:15  4.9  1.70 165
PPM 047955     05:18:15.7 +42:47:30  7.0  0.55 164
PPM 047931     05:17:06.6 +43:25:39  9.8  0.16 164
181855         05:17:47.2 +43:19:55 15.1       164
Positions are for J2000

Event circumstances last updated at 2022/03/24 00:37:59 UT

Marc W. Buie, Southwest Research Institute

RECON