RECON: TNO occultation with 181855

Event between (181855) 98WT31 and star GA1320:02649907 with event index number of 1211430

Geocentric closest approach at 2023/04/01 04:39:00 UTC

J2000 position of star is 05:07:35.0 +42:02:43
Equinox of date position of star is 05:09:11.6 +42:04:25
Stellar brightness G=15.6, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 56 degrees from the moon. Moon is 78% illuminated.
TNO apparent brightness V=23.6

[RECON map]
TNO is 37.6 AU from the Sun and 37.9 AU from the Earth.
The TNO is moving 16.8 km/sec on the sky relative to the star, or, 2.2 arcsec/hr.
The 1-sigma error in the time of the event is 283 seconds.
The 1-sigma cross-track error in the shadow position is 3432 km.
The sky-plane scale is 27507.2 km/arcsec.

The TNO has an absolute magnitude Hv=7.7
Diameter=173.8 km assuming a 5% albedo -- 10.3 sec chord
Diameter=70.9 km assuming a 30% albedo -- 4.2 sec chord
Dynamical classification is SCATEXTD
 
 
 
 
 
 

Star training set for 181855, (2023/04/01 04:29UT)
Object            RA         Dec     mag  sep  mel
Aldebaran      04:37:15.4 +16:33:15  0.8 26.42  66
3Iot Aur       04:58:30.7 +33:12:03  2.7  9.12  58
10Eta Aur      05:08:09.0 +41:15:49  3.2  0.84  56
PPM 047736     05:08:57.2 +42:07:28  8.0  0.07  55
PPM 047743     05:09:28.6 +42:02:23  9.3  0.06  55
181855         05:09:13.8 +42:04:27 15.6        55
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 3.2 sigma about the mid-time.
The median site spacing is 10.3 km RECON observability=1.0 and success probability=5.7%
Site Site mid-time
(UT)
Sun alt
(deg)
Sky Moon Star alt
(deg)
Star az
(deg)
Target Observing Time
(UT)
X-track
(km)
Sleaford 04:41:27 -25.5 Dark Up 39.2 291.0 Up 04:26:27 - 04:56:27 6980
Dunrhomin 04:42:35 -34.7 Dark Up 33.5 299.5 Up 04:27:35 - 04:57:35 6580
CU-SBO 04:42:34 -34.8 Dark Up 33.4 299.6 Up 04:27:34 - 04:57:34 6563
Kelowna 04:41:33 -20.7 Dark Up 46.6 284.9 Up 04:26:33 - 04:56:33 6218
Kamloops 04:41:28 -19.7 Dark Up 47.4 283.5 Up 04:26:28 - 04:56:28 6211
Penticton 04:41:35 -20.8 Dark Up 46.6 285.2 Up 04:26:35 - 04:56:35 6198
Peachland 04:41:33 -20.6 Dark Up 46.8 284.9 Up 04:26:33 - 04:56:33 6198
Summerland 04:41:35 -20.7 Dark Up 46.7 285.1 Up 04:26:35 - 04:56:35 6195
Anarchist Mountain Observatory 04:41:37 -21.2 Dark Up 46.3 285.9 Up 04:26:37 - 04:56:37 6183
Oliver 04:41:37 -21.0 Dark Up 46.5 285.6 Up 04:26:37 - 04:56:37 6181
Tonasket 04:41:40 -21.4 Dark Up 46.3 286.1 Up 04:26:40 - 04:56:40 6164
Okanogan 04:41:41 -21.5 Dark Up 46.3 286.4 Up 04:26:41 - 04:56:41 6140
Brewster 04:41:43 -21.6 Dark Up 46.3 286.6 Up 04:26:43 - 04:56:43 6116
Manson/Chelan 04:41:44 -21.5 Dark Up 46.5 286.6 Up 04:26:44 - 04:56:44 6086
PNWRO 04:41:55 -23.3 Dark Up 45.1 289.1 Up 04:26:55 - 04:56:55 6060
Wenatchee 04:41:46 -21.6 Dark Up 46.5 287.0 Up 04:26:46 - 04:56:46 6052
Ellensburg 04:41:48 -21.7 Dark Up 46.5 287.3 Up 04:26:48 - 04:56:48 6019
Yakima 04:41:51 -22.0 Dark Up 46.4 287.7 Up 04:26:51 - 04:56:51 5997
Toppenish/White Swan 04:41:53 -22.2 Dark Up 46.2 288.0 Up 04:26:53 - 04:56:53 5996
Victoria 04:41:36 -19.3 Dark Up 48.8 284.1 Up 04:26:36 - 04:56:36 5944
Goldendale 04:41:56 -22.2 Dark Up 46.3 288.3 Up 04:26:56 - 04:56:56 5943
The Dalles 04:41:56 -22.2 Dark Up 46.5 288.4 Up 04:26:56 - 04:56:56 5910
Maupin 04:41:59 -22.4 Dark Up 46.2 288.8 Up 04:26:59 - 04:56:59 5894
George/Scottsdale 04:43:07 -34.9 Dark Up 34.7 301.1 Up 04:28:07 - 04:58:07 5836
Bend 04:42:04 -22.9 Dark Up 46.0 289.8 Up 04:27:04 - 04:57:04 5820
Sisters 04:42:02 -22.6 Dark Up 46.3 289.5 Up 04:27:02 - 04:57:02 5818
Oregon Observatory 04:42:05 -22.9 Dark Up 46.0 290.0 Up 04:27:05 - 04:57:05 5803
Patrick 04:42:57 -32.6 Dark Up 37.0 299.5 Up 04:27:57 - 04:57:57 5800
North Lake 04:42:09 -23.6 Dark Up 45.4 290.8 Up 04:27:09 - 04:57:09 5800
Kingman/Dolan Springs 04:42:57 -32.6 Dark Up 37.1 299.6 Up 04:27:57 - 04:57:57 5775
Lakeview 04:42:16 -24.5 Dark Up 44.7 292.0 Up 04:27:16 - 04:57:16 5774
Henderson 04:42:52 -31.5 Dark Up 38.1 298.8 Up 04:27:52 - 04:57:52 5763
Indian Springs 04:42:49 -30.7 Dark Up 38.9 298.2 Up 04:27:49 - 04:57:49 5749
Cedarville 04:42:18 -25.0 Dark Up 44.3 292.7 Up 04:27:18 - 04:57:18 5748
Laughlin/Bullhead City 04:42:56 -32.2 Dark Up 37.4 299.5 Up 04:27:56 - 04:57:56 5740
Tonopah 04:42:42 -28.8 Dark Up 40.7 296.7 Up 04:27:42 - 04:57:42 5735
Mohave Valley 04:42:58 -32.4 Dark Up 37.3 299.7 Up 04:27:58 - 04:57:58 5725
Lake Havasu City 04:43:02 -32.8 Dark Up 36.9 300.0 Up 04:28:02 - 04:58:02 5718
Chiloquin 04:42:11 -23.4 Dark Up 45.8 291.1 Up 04:27:11 - 04:57:11 5705
Parker 04:43:02 -33.0 Dark Up 36.7 300.3 Up 04:28:02 - 04:58:02 5700
Beatty 04:42:46 -29.8 Dark Up 39.8 297.7 Up 04:27:46 - 04:57:46 5698
Klamath Falls 04:42:13 -23.6 Dark Up 45.7 291.4 Up 04:27:13 - 04:57:13 5691
Hawthorne 04:42:35 -27.6 Dark Up 41.9 295.8 Up 04:27:35 - 04:57:35 5672
Yerington 04:42:34 -27.0 Dark Up 42.5 295.3 Up 04:27:34 - 04:57:34 5666
Reno 04:42:30 -26.3 Dark Up 43.2 294.6 Up 04:27:30 - 04:57:30 5657
Susanville 04:42:24 -25.3 Dark Up 44.2 293.5 Up 04:27:24 - 04:57:24 5655
Fall River/Burney 04:42:20 -24.5 Dark Up 44.9 292.7 Up 04:27:20 - 04:57:20 5646
Carson City 04:42:33 -26.5 Dark Up 43.0 294.9 Up 04:27:33 - 04:57:33 5638
Portola 04:42:28 -25.7 Dark Up 43.8 294.1 Up 04:27:28 - 04:57:28 5632
Gardnerville 04:42:34 -26.7 Dark Up 42.9 295.1 Up 04:27:34 - 04:57:34 5626
Gimple 04:42:26 -25.3 Dark Up 44.2 293.7 Up 04:27:26 - 04:57:26 5626
Greenville 04:42:26 -25.2 Dark Up 44.2 293.7 Up 04:27:26 - 04:57:26 5621
Bishop 04:42:43 -28.4 Dark Up 41.2 296.8 Up 04:27:43 - 04:57:43 5620
Quincy 04:42:26 -25.3 Dark Up 44.2 293.9 Up 04:27:26 - 04:57:26 5610
Lee Vining 04:42:39 -27.6 Dark Up 42.0 296.1 Up 04:27:39 - 04:57:39 5609
Yuma 04:43:09 -33.6 Dark Up 36.2 301.1 Up 04:28:09 - 04:58:09 5593
Calipatria 04:43:06 -32.7 Dark Up 37.0 300.6 Up 04:28:06 - 04:58:06 5559
Idyllwild 04:43:02 -31.5 Dark Up 38.2 299.9 Up 04:28:02 - 04:58:02 5517
Wildwood 04:43:00 -30.0 Dark Up 39.8 299.3 Up 04:28:00 - 04:58:00 5412

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, (2023/04/01 04:29UT)
Object            RA         Dec     mag  sep  mel
Aldebaran      04:35:55.3 +16:30:29  0.8 26.42  66
3Iot Aur       04:56:59.6 +33:09:58  2.7  9.12  58
10Eta Aur      05:06:30.9 +41:14:03  3.2  0.84  56
PPM 047736     05:07:18.4 +42:05:44  8.0  0.07  55
PPM 047743     05:07:49.9 +42:00:40  9.3  0.06  55
181855         05:07:35.0 +42:02:43 15.6        55
Positions are for J2000

Event circumstances last updated at 2022/09/30 04:16:55 UT

Marc W. Buie, Southwest Research Institute

RECON