RECON: TNO occultation with 5145

Event between (5145) Pholus and star GA0740:21790921 with event index number of 1402407

Geocentric closest approach at 2025/06/29 06:16:56 UTC

J2000 position of star is 18:40:00.4 -14:01:32
Equinox of date position of star is 18:41:23.6 -14:00:06
Stellar brightness G=16.5, use SENSEUP=128 with the MallinCam and and exposure time of 2 seconds with the QHY174 camera.
Star is 132 degrees from the moon. Moon is 17% illuminated.
Apparent brightness V=21.9

[RECON map]
Object is 30.3 AU from the Sun and 29.3 AU from the Earth.
Apparent velocity is 26.0 km/sec on the sky relative to the star, or, 4.4 arcsec/hr.
The 1-sigma error in the time of the event is 112 seconds.
The 1-sigma cross-track error in the shadow position is 1474 km.
The sky-plane scale is 21274.5 km/arcsec.

The object has an absolute magnitude Hv=7.1
Diameter=229.1 km assuming a 5% albedo -- 8.9 sec chord
Diameter=93.5 km assuming a 30% albedo -- 3.6 sec chord
Dynamical classification is CENTAURR
 
 
 
 
 
 

Star training set for 5145, (2025/06/29 06:17UT)
Object            RA         Dec     mag  sep  mel
Antares        16:30:58.5 -26:29:11  0.9 32.93 103
Nunki          18:56:50.6 -26:15:46  2.0 12.78 135
PPM 234707     18:35:06.4 -14:49:57  6.1  1.75 130
PPM 234837     18:40:19.8 -13:45:09  7.8  0.37 131
PPM 234847     18:40:52.8 -13:49:18  9.5  0.23 131
5145           18:41:27.2 -14:00:02 16.5       132
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 21.1 km RECON observability=0.8 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 06:17:07 -13.9 AT Down 22.8 165.2 Low 06:07:18 - 06:26:56 6820
Kamloops 06:17:45 -12.4 AT Up 20.7 150.5 Low 06:07:56 - 06:27:34 6781
Kelowna 06:17:43 -13.4 AT Up 21.7 151.2 Low 06:07:54 - 06:27:32 6744
Peachland 06:17:45 -13.4 AT Up 21.7 150.9 Low 06:07:56 - 06:27:34 6739
Summerland 06:17:45 -13.6 AT Up 21.9 151.0 Low 06:07:56 - 06:27:34 6732
Penticton 06:17:45 -13.7 AT Up 22.0 151.1 Low 06:07:56 - 06:27:34 6729
Oliver 06:17:45 -14.0 AT Up 22.3 151.0 Low 06:07:56 - 06:27:34 6712
Anarchist Mountain Observatory 06:17:45 -14.2 AT Up 22.5 151.2 Low 06:07:56 - 06:27:34 6705
Victoria 06:17:56 -13.5 AT Up 21.5 147.1 Low 06:08:07 - 06:27:45 6676
Okanogan 06:17:47 -14.7 AT Up 23.0 150.8 Low 06:07:58 - 06:27:36 6673
Brewster 06:17:48 -14.9 AT Up 23.1 150.6 Low 06:07:59 - 06:27:37 6659
Manson/Chelan 06:17:49 -15.0 AT Up 23.2 150.2 Low 06:08:00 - 06:27:38 6649
Wenatchee 06:17:50 -15.4 AT Up 23.6 149.9 Low 06:08:01 - 06:27:39 6625
Ellensburg 06:17:52 -15.7 AT Up 23.8 149.6 Low 06:08:03 - 06:27:41 6604
Yakima 06:17:52 -16.1 AT Up 24.2 149.5 Low 06:08:03 - 06:27:41 6583
Toppenish/White Swan 06:17:52 -16.3 AT Up 24.4 149.6 Low 06:08:03 - 06:27:41 6572
PNWRO 06:17:49 -17.1 AT Up 25.3 151.0 Low 06:08:00 - 06:27:38 6553
The Dalles 06:17:56 -16.8 AT Up 24.8 148.7 Low 06:08:07 - 06:27:45 6530
Maupin 06:17:56 -17.2 AT Up 25.2 148.7 Low 06:08:07 - 06:27:45 6507
Sisters 06:18:00 -17.8 AT Up 25.8 148.0 Low 06:08:11 - 06:27:49 6459
Bend 06:17:59 -18.1 Dark Up 26.1 148.2 Low 06:08:10 - 06:27:48 6446
Oregon Observatory 06:17:59 -18.2 Dark Up 26.2 148.0 Low 06:08:10 - 06:27:48 6436
Chiloquin 06:18:03 -19.3 Dark Up 27.1 147.2 Low 06:08:14 - 06:27:52 6360
Klamath Falls 06:18:03 -19.6 Dark Up 27.5 147.2 Low 06:08:14 - 06:27:52 6340
Cedarville 06:18:00 -20.7 Dark Up 28.7 148.6 Low 06:08:11 - 06:27:49 6300
Fall River/Burney 06:18:04 -20.8 Dark Up 28.6 147.3 Low 06:08:15 - 06:27:53 6269
Greenville 06:18:04 -21.7 Dark Up 29.6 147.4 Low 06:08:15 - 06:27:53 6213
Gimple 06:18:04 -21.8 Dark Up 29.6 147.5 Low 06:08:15 - 06:27:53 6213
Quincy 06:18:05 -21.9 Dark Up 29.7 147.4 Low 06:08:16 - 06:27:54 6201
Portola 06:18:04 -22.2 Dark Up 30.0 147.8 Up 06:08:15 - 06:27:53 6194
Dunrhomin 06:17:17 -25.6 Dark Down 34.3 164.4 Up 06:07:28 - 06:27:06 6189
Nikitin 06:17:17 -25.8 Dark Down 34.5 164.3 Up 06:07:28 - 06:27:06 6178
Reno 06:18:02 -22.6 Dark Down 30.5 148.4 Up 06:08:13 - 06:27:51 6177
CU-SBO 06:17:17 -25.8 Dark Down 34.6 164.2 Up 06:07:28 - 06:27:06 6174
Carson City 06:18:02 -23.0 Dark Down 30.8 148.3 Up 06:08:13 - 06:27:51 6154
Yerington 06:18:01 -23.4 Dark Down 31.3 148.9 Up 06:08:12 - 06:27:50 6142
Gardnerville 06:18:03 -23.2 Dark Down 31.1 148.3 Up 06:08:14 - 06:27:52 6139
Hawthorne 06:18:00 -24.0 Dark Down 31.9 149.3 Up 06:08:11 - 06:27:49 6112
Lee Vining 06:18:02 -24.3 Dark Down 32.2 148.6 Up 06:08:13 - 06:27:51 6075
Bishop 06:18:01 -25.1 Dark Down 33.0 149.2 Up 06:08:12 - 06:27:50 6035
Beatty 06:17:57 -26.0 Dark Down 34.0 150.7 Up 06:08:08 - 06:27:46 6003
Patrick 06:17:50 -28.3 Dark Down 36.4 153.4 Up 06:08:01 - 06:27:39 5898
Laughlin/Bullhead City 06:17:52 -28.3 Dark Down 36.4 152.5 Up 06:08:03 - 06:27:41 5881
Lake Havasu City 06:17:52 -29.0 Dark Down 37.1 152.6 Up 06:08:03 - 06:27:41 5833
Wildwood 06:18:06 -28.0 Dark Down 35.7 147.8 Up 06:08:17 - 06:27:55 5808
Idyllwild 06:18:01 -29.0 Dark Down 36.8 149.7 Up 06:08:12 - 06:27:50 5782
George/Scottsdale 06:17:45 -30.5 Dark Down 38.7 155.1 Up 06:07:56 - 06:27:34 5772
Calipatria 06:17:58 -29.9 Dark Down 37.8 150.8 Up 06:08:09 - 06:27:47 5736
Yuma 06:17:56 -30.6 Dark Down 38.5 151.6 Up 06:08:07 - 06:27:45 5703

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 5145, (2025/06/29 06:17UT)
Object            RA         Dec     mag  sep  mel
Antares        16:29:24.4 -26:25:56  0.9 32.93 103
Nunki          18:55:15.9 -26:17:49  2.0 12.78 135
PPM 234707     18:33:39.1 -14:51:14  6.1  1.75 130
PPM 234837     18:38:53.2 -13:46:37  7.8  0.37 131
PPM 234847     18:39:26.1 -13:50:47  9.5  0.23 131
5145           18:40:00.4 -14:01:32 16.5       132
Positions are for J2000

Event circumstances last updated at 2024/06/13 03:57:04 UT

Marc W. Buie, Southwest Research Institute

RECON