RECON: TNO occultation with 99RW215

Event between 99RW215 and star GA1120:00753684 with event index number of 1490706

Geocentric closest approach at 2025/09/03 10:31:49 UTC

J2000 position of star is 04:42:46.6 +22:44:07
Equinox of date position of star is 04:43:56.7 +22:46:15
Stellar brightness G=15.5, use SENSEUP=128
Star is 145 degrees from the moon. Moon is 79% illuminated.
TNO apparent brightness V=23.0

[RECON map]
TNO is 30.7 AU from the Sun and 30.7 AU from the Earth.
The TNO is moving 6.0 km/sec on the sky relative to the star, or, 1.0 arcsec/hr.
The 1-sigma error in the time of the event is 8395 seconds.
The 1-sigma cross-track error in the shadow position is 3513 km.
The sky-plane scale is 22291.1 km/arcsec.

The TNO has an absolute magnitude Hv=7.9
Diameter=156.3 km assuming a 5% albedo -- 25.9 sec chord
Diameter=63.8 km assuming a 30% albedo -- 10.6 sec chord
Dynamical classification is 4:3E
 
 
 
 
 
 

Star training set for 99RW215, (2025/09/03 10:32UT)
Object            RA         Dec     mag  sep  mel
Aldebaran      04:37:23.8 +16:33:33  0.8  6.43 141
3Iot Aur       04:58:40.2 +33:12:15  2.7 10.89 149
PPM 093742     04:47:15.7 +23:40:24  6.1  1.12 146
PPM 093707     04:43:44.8 +22:59:23  7.2  0.25 145
PPM 093716     04:44:16.4 +22:39:08 10.6  0.13 145
99RW215        04:44:19.1 +22:46:55 15.5       145
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 0.1 sigma about the mid-time.
The median site spacing is 19.9 km RECON observability=1.0 and success probability=12.7%
Site Site mid-time
(UT)
Sun alt
(deg)
Sky Moon Star alt
(deg)
Star az
(deg)
Target Observing Time
(UT)
X-track
(km)
Kelowna 10:22:58 -24.5 Dark Down 41.7 104.7 Up 10:07:58 - 10:37:58 2958
Summerland 10:22:53 -24.9 Dark Down 41.6 104.2 Up 10:07:53 - 10:37:53 2939
Penticton 10:22:53 -24.9 Dark Down 41.7 104.2 Up 10:07:53 - 10:37:53 2931
Okanagan Falls 10:22:50 -25.0 Dark Down 41.7 104.1 Up 10:07:50 - 10:37:50 2915
Oliver 10:22:49 -25.2 Dark Down 41.7 103.9 Up 10:07:49 - 10:37:49 2900
Anarchist Mountain Observatory 10:22:48 -25.2 Dark Down 41.9 103.9 Up 10:07:48 - 10:37:48 2881
Oroville 10:22:47 -25.3 Dark Down 41.9 103.8 Up 10:07:47 - 10:37:47 2876
Tonasket 10:22:44 -25.5 Dark Down 41.9 103.6 Up 10:07:44 - 10:37:44 2856
Okanogan 10:22:39 -25.8 Dark Down 41.9 103.2 Up 10:07:39 - 10:37:39 2830
Brewster 10:22:35 -26.1 Dark Down 41.8 102.7 Up 10:07:35 - 10:37:35 2811
Manson/Chelan 10:22:29 -26.4 Dark Down 41.6 102.2 Up 10:07:29 - 10:37:29 2802
Entiat 10:22:26 -26.7 Dark Down 41.6 101.9 Up 10:07:26 - 10:37:26 2784
Wenatchee 10:22:22 -26.9 Dark Down 41.6 101.6 Up 10:07:22 - 10:37:22 2764
Ellensburg 10:22:16 -27.3 Dark Down 41.5 101.1 Up 10:07:16 - 10:37:16 2733
Yakima 10:22:12 -27.6 Dark Down 41.5 100.7 Up 10:07:12 - 10:37:12 2698
Toppenish/White Swan 10:22:10 -27.7 Dark Down 41.7 100.6 Up 10:07:10 - 10:37:10 2674
Goldendale 10:22:03 -28.4 Dark Down 41.5 99.8 Up 10:07:03 - 10:37:03 2636
Pasco 10:22:20 -27.2 Dark Down 42.6 101.6 Up 10:07:20 - 10:37:20 2633
The Dalles 10:21:56 -28.7 Dark Down 41.2 99.2 Up 10:06:56 - 10:36:56 2625
George/Umatilla 10:22:14 -27.6 Dark Down 42.5 101.1 Up 10:07:14 - 10:37:14 2608
PNWRO 10:22:20 -27.3 Dark Down 42.8 101.6 Up 10:07:20 - 10:37:20 2605
Maupin 10:21:53 -29.0 Dark Down 41.4 98.9 Up 10:06:53 - 10:36:53 2585
Madras/Culver 10:21:47 -29.4 Dark Down 41.4 98.4 Up 10:06:47 - 10:36:47 2537
Sisters 10:21:40 -29.9 Dark Down 41.1 97.7 Up 10:06:40 - 10:36:40 2518
Redmond 10:21:42 -29.7 Dark Down 41.4 98.0 Up 10:06:42 - 10:36:42 2506
Bend 10:21:38 -30.0 Dark Down 41.3 97.7 Up 10:06:38 - 10:36:38 2490
Oregon Observatory 10:21:35 -30.2 Dark Down 41.2 97.5 Up 10:06:35 - 10:36:35 2478
La Pine/Gilchrist 10:21:33 -30.4 Dark Down 41.2 97.2 Up 10:06:33 - 10:36:33 2461
North Lake 10:21:32 -30.4 Dark Down 41.7 97.3 Up 10:06:32 - 10:36:32 2406
Chiloquin 10:21:19 -31.4 Dark Down 41.0 96.0 Up 10:06:19 - 10:36:19 2369
Paisley 10:21:31 -30.7 Dark Down 42.0 97.1 Up 10:06:31 - 10:36:31 2346
Klamath Falls 10:21:16 -31.6 Dark Down 41.1 95.7 Up 10:06:16 - 10:36:16 2336
Tulelake 10:21:14 -31.7 Dark Down 41.4 95.7 Up 10:06:14 - 10:36:14 2303
Lakeview 10:21:26 -31.0 Dark Down 42.2 96.8 Up 10:06:26 - 10:36:26 2294
Cedarville 10:21:21 -31.4 Dark Down 42.4 96.3 Up 10:06:21 - 10:36:21 2229
Fall River/Burney 10:21:06 -32.4 Dark Down 41.5 94.9 Up 10:06:06 - 10:36:06 2217
Susanville 10:21:06 -32.5 Dark Down 42.1 94.9 Up 10:06:06 - 10:36:06 2138
Greenville 10:21:01 -32.8 Dark Down 41.9 94.4 Up 10:06:01 - 10:36:01 2120
Gimple 10:21:02 -32.8 Dark Down 42.0 94.5 Up 10:06:02 - 10:36:02 2117
Quincy 10:20:58 -33.0 Dark Down 41.9 94.2 Up 10:05:58 - 10:35:58 2101
Portola 10:21:02 -32.8 Dark Down 42.3 94.5 Up 10:06:02 - 10:36:02 2076
Reno 10:21:04 -32.7 Dark Down 42.8 94.7 Up 10:06:04 - 10:36:04 2033
Carson City 10:21:02 -32.9 Dark Down 42.9 94.4 Up 10:06:02 - 10:36:02 1998
Gardnerville 10:20:59 -33.1 Dark Down 42.9 94.2 Up 10:05:59 - 10:35:59 1974
Yerington 10:21:05 -32.7 Dark Down 43.4 94.6 Up 10:06:05 - 10:36:05 1962
Hawthorne 10:21:04 -32.8 Dark Down 43.8 94.6 Up 10:06:04 - 10:36:04 1903
Lee Vining 10:20:56 -33.5 Dark Down 43.4 93.7 Up 10:05:56 - 10:35:56 1863
Tonopah 10:21:15 -32.3 Dark Down 45.0 95.1 Up 10:06:15 - 10:36:15 1820
Bishop 10:20:57 -33.5 Dark Down 44.1 93.6 Up 10:05:57 - 10:35:57 1785
Niwot 10:23:38 -23.3 Dark Down 54.2 107.7 Up 10:08:38 - 10:38:38 1734
SwRI 10:23:38 -23.4 Dark Down 54.2 107.5 Up 10:08:38 - 10:38:38 1725
Lone Pine 10:20:53 -33.8 Dark Down 44.4 93.0 Up 10:05:53 - 10:35:53 1702
Beatty 10:21:09 -32.8 Dark Down 45.4 94.2 Up 10:06:09 - 10:36:09 1695
CPSLO 10:20:17 -36.3 Dark Down 42.2 90.1 Up 10:05:17 - 10:35:17 1650
Indian Springs 10:21:16 -32.4 Dark Down 46.3 94.6 Up 10:06:16 - 10:36:16 1634
Henderson 10:21:19 -32.3 Dark Down 47.0 94.5 Up 10:06:19 - 10:36:19 1563
Searchlight/Boulder City 10:21:15 -32.6 Dark Down 47.0 93.9 Up 10:06:15 - 10:36:15 1504
Wildwood 10:20:26 -35.9 Dark Down 43.9 90.2 Up 10:05:26 - 10:35:26 1471
Patrick 10:21:25 -32.0 Dark Down 47.9 94.6 Up 10:06:25 - 10:36:25 1470
Laughlin/Bullhead City 10:21:16 -32.6 Dark Down 47.3 93.8 Up 10:06:16 - 10:36:16 1465
Kingman/Dolan Springs 10:21:21 -32.2 Dark Down 47.8 94.2 Up 10:06:21 - 10:36:21 1453
Mohave Valley 10:21:13 -32.8 Dark Down 47.4 93.5 Up 10:06:13 - 10:36:13 1438
DCO 10:21:29 -31.7 Dark Down 48.5 94.7 Up 10:06:29 - 10:36:29 1421
Lake Havasu City 10:21:12 -32.9 Dark Down 47.6 93.3 Up 10:06:12 - 10:36:12 1391
Idyllwild 10:20:41 -35.0 Dark Down 45.5 91.0 Up 10:05:41 - 10:35:41 1381
Parker 10:21:09 -33.1 Dark Down 47.6 92.9 Up 10:06:09 - 10:36:09 1355
Blythe 10:21:03 -33.6 Dark Down 47.4 92.1 Up 10:06:03 - 10:36:03 1310
Calipatria 10:20:48 -34.6 Dark Down 46.5 91.0 Up 10:05:48 - 10:35:48 1287
Yuma 10:20:55 -34.2 Dark Down 47.3 91.1 Up 10:05:55 - 10:35:55 1218

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 99RW215, (2025/09/03 10:32UT)
Object            RA         Dec     mag  sep  mel
Aldebaran      04:35:55.3 +16:30:30  0.8  6.43 141
3Iot Aur       04:56:59.6 +33:09:58  2.7 10.89 149
PPM 093742     04:45:42.5 +23:37:41  6.1  1.12 146
PPM 093707     04:42:12.2 +22:56:33  7.2  0.25 145
PPM 093716     04:42:44.0 +22:36:19 10.6  0.13 145
99RW215        04:42:46.6 +22:44:07 15.5       145
Positions are for J2000

Event circumstances last updated at 2019/06/08 12:55:53 UT

Marc W. Buie, Southwest Research Institute

RECON