RECON: TNO occultation with 04HX78

Event between 04HX78 and star GA0780:10946460 with event index number of 1449424

Geocentric closest approach at 2026/05/21 09:01:27 UTC

J2000 position of star is 18:24:28.2 -11:07:40
Equinox of date position of star is 18:25:33.6 -11:06:57
Stellar brightness G=14.4, use SENSEUP=128
Star is 149 degrees from the moon. Moon is 28% illuminated.
TNO apparent brightness V=23.6

[RECON map]
TNO is 33.9 AU from the Sun and 33.1 AU from the Earth.
The TNO is moving 18.8 km/sec on the sky relative to the star, or, 2.8 arcsec/hr.
The 1-sigma error in the time of the event is 541 seconds.
The 1-sigma cross-track error in the shadow position is 3169 km.
The sky-plane scale is 24010.7 km/arcsec.

The TNO has an absolute magnitude Hv=8.2
Diameter=141.9 km assuming a 5% albedo -- 7.4 sec chord
Diameter=57.9 km assuming a 30% albedo -- 3.0 sec chord
Dynamical classification is 3:2E
 
 
 
 
 
 

Star training set for 04HX78, (2026/05/21 09:01UT)
Object            RA         Dec     mag  sep  mel
Antares        16:31:01.8 -26:29:17  0.9 31.12 126
Nunki          18:56:54.0 -26:15:41  2.0 16.82 159
PPM 234462     18:24:40.8 -11:59:58  6.3  0.94 149
PPM 234491     18:25:57.2 -10:23:55  8.1  0.71 149
PPM 234486     18:25:42.6 -11:13:34  9.1  0.13 149
04HX78         18:25:56.2 -11:06:42 14.4       149
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 1.7 sigma about the mid-time.
The median site spacing is 14.9 km RECON observability=1.0 and success probability=4.1%
Site Site mid-time
(UT)
Sun alt
(deg)
Sky Moon Star alt
(deg)
Star az
(deg)
Target Observing Time
(UT)
X-track
(km)
Kelowna 09:03:42 -18.2 Dark Down 26.4 157.4 Low 08:48:42 - 09:18:42 6609
Summerland 09:03:45 -18.5 Dark Down 26.6 157.0 Low 08:48:45 - 09:18:45 6586
Penticton 09:03:43 -18.6 Dark Down 26.7 157.1 Low 08:48:43 - 09:18:43 6584
Okanagan Falls 09:03:44 -18.8 Dark Down 26.8 157.1 Low 08:48:44 - 09:18:44 6572
Oliver 09:03:44 -18.9 Dark Down 27.0 157.1 Low 08:48:44 - 09:18:44 6563
Anarchist Mountain Observatory 09:03:43 -19.1 Dark Down 27.2 157.2 Low 08:48:43 - 09:18:43 6556
Oroville 09:03:44 -19.1 Dark Down 27.2 157.1 Low 08:48:44 - 09:18:44 6550
Tonasket 09:03:43 -19.4 Dark Down 27.5 157.1 Low 08:48:43 - 09:18:43 6535
Okanogan 09:03:44 -19.7 Dark Down 27.7 156.9 Low 08:48:44 - 09:18:44 6512
Brewster 09:03:46 -20.0 Dark Down 27.9 156.6 Low 08:48:46 - 09:18:46 6491
Manson/Chelan 09:03:47 -20.3 Dark Down 28.0 156.2 Low 08:48:47 - 09:18:47 6470
Wenatchee 09:03:48 -20.8 Dark Down 28.4 155.9 Low 08:48:48 - 09:18:48 6437
Ellensburg 09:03:49 -21.2 Dark Down 28.7 155.6 Low 08:48:49 - 09:18:49 6406
Pasco 09:03:45 -21.6 Dark Down 29.8 156.9 Low 08:48:45 - 09:18:45 6386
Yakima 09:03:50 -21.6 Dark Down 29.1 155.5 Low 08:48:50 - 09:18:50 6379
PNWRO 09:03:44 -21.8 Dark Down 30.1 157.1 Up 08:48:44 - 09:18:44 6374
Toppenish/White Swan 09:03:49 -21.8 Dark Down 29.3 155.6 Low 08:48:49 - 09:18:49 6368
Goldendale 09:03:51 -22.4 Dark Down 29.7 155.0 Low 08:48:51 - 09:18:51 6323
The Dalles 09:03:53 -22.7 Dark Down 29.8 154.6 Low 08:48:53 - 09:18:53 6301
Maupin 09:03:53 -23.0 Dark Down 30.2 154.6 Up 08:48:53 - 09:18:53 6275
Madras/Culver 09:03:53 -23.6 Dark Down 30.7 154.4 Up 08:48:53 - 09:18:53 6237
SwRI 09:02:52 -23.1 Dark Down 38.5 171.7 Up 08:47:52 - 09:17:52 6235
Redmond 09:03:54 -23.9 Dark Down 31.0 154.3 Up 08:48:54 - 09:18:54 6211
Sisters 09:03:55 -24.0 Dark Down 30.9 153.8 Up 08:48:55 - 09:18:55 6204
Bend 09:03:55 -24.2 Dark Down 31.2 154.1 Up 08:48:55 - 09:18:55 6193
Oregon Observatory 09:03:54 -24.4 Dark Down 31.3 153.9 Up 08:48:54 - 09:18:54 6178
La Pine/Gilchrist 09:03:56 -24.6 Dark Down 31.4 153.7 Up 08:48:56 - 09:18:56 6163
North Lake 09:03:54 -24.9 Dark Down 32.0 154.3 Up 08:48:54 - 09:18:54 6145
Paisley 09:03:53 -25.3 Dark Down 32.6 154.5 Up 08:48:53 - 09:18:53 6114
Lakeview 09:03:52 -25.8 Dark Down 33.2 154.6 Up 08:48:52 - 09:18:52 6082
Chiloquin 09:03:58 -25.7 Dark Down 32.3 153.1 Up 08:48:58 - 09:18:58 6076
Klamath Falls 09:03:59 -26.0 Dark Down 32.7 153.1 Up 08:48:59 - 09:18:59 6054
Tulelake 09:03:56 -26.2 Dark Down 33.0 153.3 Up 08:48:56 - 09:18:56 6041
Cedarville 09:03:52 -26.4 Dark Down 33.8 154.6 Up 08:48:52 - 09:18:52 6038
Fall River/Burney 09:03:57 -27.1 Dark Down 33.8 153.1 Up 08:48:57 - 09:18:57 5976
Susanville 09:03:55 -27.5 Dark Down 34.7 153.7 Up 08:48:55 - 09:18:55 5946
Gimple 09:03:56 -27.8 Dark Down 34.8 153.4 Up 08:48:56 - 09:18:56 5920
Greenville 09:03:56 -27.8 Dark Down 34.8 153.3 Up 08:48:56 - 09:18:56 5919
Portola 09:03:55 -28.1 Dark Down 35.3 153.8 Up 08:48:55 - 09:18:55 5905
Quincy 09:03:57 -28.0 Dark Down 35.0 153.3 Up 08:48:57 - 09:18:57 5904
Reno 09:03:52 -28.2 Dark Down 35.7 154.4 Up 08:48:52 - 09:18:52 5899
Carson City 09:03:52 -28.5 Dark Down 36.0 154.3 Up 08:48:52 - 09:18:52 5873
Yerington 09:03:49 -28.5 Dark Down 36.4 155.0 Up 08:48:49 - 09:18:49 5872
Gardnerville 09:03:52 -28.7 Dark Down 36.3 154.3 Up 08:48:52 - 09:18:52 5855
Hawthorne 09:03:47 -28.8 Dark Down 37.0 155.4 Up 08:48:47 - 09:18:47 5849
Tonopah 09:03:42 -28.9 Dark Down 37.9 156.9 Up 08:48:42 - 09:18:42 5845
Lee Vining 09:03:49 -29.5 Dark Down 37.4 154.7 Up 08:48:49 - 09:18:49 5795
Beatty 09:03:40 -29.8 Dark Down 39.1 157.1 Up 08:48:40 - 09:18:40 5766
Bishop 09:03:47 -29.9 Dark Down 38.2 155.3 Up 08:48:47 - 09:18:47 5765
Indian Springs 09:03:36 -29.8 Dark Down 39.7 158.3 Up 08:48:36 - 09:18:36 5765
Henderson 09:03:33 -30.1 Dark Down 40.4 158.9 Up 08:48:33 - 09:18:33 5738
Patrick 09:03:28 -30.3 Dark Down 41.3 160.1 Up 08:48:28 - 09:18:28 5714
Lone Pine 09:03:46 -30.5 Dark Down 39.0 155.5 Up 08:48:46 - 09:18:46 5713
Searchlight/Boulder City 09:03:33 -30.6 Dark Down 41.0 158.8 Up 08:48:33 - 09:18:33 5695
Kingman/Dolan Springs 09:03:29 -30.6 Dark Down 41.5 159.8 Up 08:48:29 - 09:18:29 5692
Laughlin/Bullhead City 09:03:31 -30.8 Dark Down 41.4 159.2 Up 08:48:31 - 09:18:31 5679
Mohave Valley 09:03:31 -31.0 Dark Down 41.6 159.1 Up 08:48:31 - 09:18:31 5658
Lake Havasu City 09:03:30 -31.3 Dark Down 42.1 159.3 Up 08:48:30 - 09:18:30 5631
George/Scottsdale 09:03:19 -31.1 Dark Down 43.5 162.1 Up 08:48:19 - 09:18:19 5624
Parker 09:03:30 -31.6 Dark Down 42.4 159.2 Up 08:48:30 - 09:18:30 5604
Blythe 09:03:31 -32.2 Dark Down 42.8 158.6 Up 08:48:31 - 09:18:31 5555
CPSLO 09:03:57 -32.4 Dark Down 39.2 152.0 Up 08:48:57 - 09:18:57 5550
Idyllwild 09:03:41 -32.8 Dark Down 42.0 156.1 Up 08:48:41 - 09:18:41 5515
Wildwood 09:03:49 -33.0 Dark Down 41.0 153.9 Up 08:48:49 - 09:18:49 5500
Calipatria 09:03:36 -32.9 Dark Down 43.0 157.3 Up 08:48:36 - 09:18:36 5493
Yuma 09:03:31 -33.0 Dark Down 43.6 158.3 Up 08:48:31 - 09:18:31 5478

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 04HX78, (2026/05/21 09:01UT)
Object            RA         Dec     mag  sep  mel
Antares        16:29:24.4 -26:25:56  0.9 31.12 126
Nunki          18:55:15.9 -26:17:49  2.0 16.82 159
PPM 234462     18:23:12.2 -12:00:54  6.3  0.94 149
PPM 234491     18:24:29.6 -10:24:54  8.1  0.71 149
PPM 234486     18:24:14.5 -11:14:32  9.1  0.13 149
04HX78         18:24:28.2 -11:07:40 14.4       149
Positions are for J2000

Event circumstances last updated at 2019/08/06 22:37:27 UT

Marc W. Buie, Southwest Research Institute

RECON