Event between (503858) 98HQ151 and star UC4-381-120941 with event index number of 227494
Geocentric closest approach at 2018/05/25 09:08:50 UTC
J2000 position of star is 18:36:07.8 -13:51:29
Equinox of date position of star is 18:37:08.8 -13:50:32
Stellar brightness R=16.2,
use SENSEUP=128
Star is 84 degrees from the moon.
Moon is 82% illuminated.
TNO apparent brightness V=23.9
[RECON map]
TNO is 32.2 AU from the Sun
and 31.3 AU from the Earth.
The TNO is moving 18.7
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 167 seconds.
The 1-sigma cross-track error in the shadow position is
1438 km.
The sky-plane scale is
22719.8 km/arcsec.
The TNO has an absolute magnitude Hv=8.8
Diameter=104.7 km assuming a 5% albedo -- 5.6 sec chord
Diameter=42.8 km assuming a 30% albedo -- 2.3 sec chord
Dynamical classification is 3:2E
Star training set for 503858, (2018/05/25 09:09UT) Object RA Dec mag sep mel Antares 16:30:32.3 -26:28:17 0.9 32.17 56 Nunki 18:56:24.3 -26:16:20 2.0 13.22 88 PPM 234707 18:34:42.1 -14:50:19 6.1 1.16 83 PPM 234768 18:37:14.9 -13:49:03 8.3 0.03 84 503858 18:37:10.4 -13:50:31 16.2 84 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 14.0 km
RECON observability=1.0 and success probability=15.5%
| Site | Site mid-time (UT) |
Sun alt (deg) |
Sky | Moon | Star alt (deg) |
Star az (deg) |
Target | Observing Time (UT) |
X-track (km) |
| Oroville | 09:10:36 | -18.1 | Dark | Up | 25.2 | 160.7 | Low | 08:56:11 - 09:25:02 | 1917 |
| Tonasket | 09:10:36 | -18.3 | Dark | Up | 25.5 | 160.7 | Low | 08:56:11 - 09:25:02 | 1904 |
| Okanogan | 09:10:37 | -18.6 | Dark | Up | 25.7 | 160.5 | Low | 08:56:12 - 09:25:03 | 1884 |
| Brewster | 09:10:38 | -18.9 | Dark | Up | 25.9 | 160.2 | Low | 08:56:12 - 09:25:03 | 1866 |
| Manson/Chelan | 09:10:39 | -19.2 | Dark | Up | 26.1 | 159.8 | Low | 08:56:14 - 09:25:05 | 1849 |
| Entiat | 09:10:40 | -19.4 | Dark | Up | 26.3 | 159.7 | Low | 08:56:14 - 09:25:05 | 1835 |
| Wenatchee | 09:10:40 | -19.7 | Dark | Up | 26.5 | 159.6 | Low | 08:56:15 - 09:25:06 | 1819 |
| Ellensburg | 09:10:42 | -20.1 | Dark | Up | 26.8 | 159.3 | Low | 08:56:17 - 09:25:08 | 1792 |
| Pasco | 09:10:37 | -20.5 | Dark | Up | 27.8 | 160.6 | Low | 08:56:12 - 09:25:03 | 1769 |
| Yakima | 09:10:42 | -20.5 | Dark | Up | 27.2 | 159.2 | Low | 08:56:17 - 09:25:08 | 1768 |
| PNWRO | 09:10:37 | -20.7 | Dark | Up | 28.1 | 160.8 | Low | 08:56:11 - 09:25:02 | 1758 |
| Toppenish/White Swan | 09:10:42 | -20.7 | Dark | Up | 27.4 | 159.3 | Low | 08:56:17 - 09:25:08 | 1758 |
| George/Umatilla | 09:10:39 | -20.9 | Dark | Up | 28.1 | 160.3 | Low | 08:56:13 - 09:25:04 | 1746 |
| Goldendale | 09:10:44 | -21.3 | Dark | Up | 27.8 | 158.8 | Low | 08:56:19 - 09:25:10 | 1719 |
| The Dalles | 09:10:46 | -21.6 | Dark | Up | 28.0 | 158.3 | Low | 08:56:20 - 09:25:11 | 1700 |
| Maupin | 09:10:46 | -22.0 | Dark | Up | 28.4 | 158.4 | Low | 08:56:20 - 09:25:11 | 1676 |
| Madras/Culver | 09:10:46 | -22.5 | Dark | Up | 28.9 | 158.2 | Low | 08:56:21 - 09:25:12 | 1641 |
| Redmond | 09:10:47 | -22.9 | Dark | Up | 29.2 | 158.1 | Low | 08:56:21 - 09:25:12 | 1618 |
| Sisters | 09:10:49 | -22.9 | Dark | Up | 29.1 | 157.7 | Low | 08:56:23 - 09:25:14 | 1614 |
| Bend | 09:10:48 | -23.1 | Dark | Up | 29.4 | 157.9 | Low | 08:56:22 - 09:25:13 | 1603 |
| Oregon Observatory | 09:10:49 | -23.3 | Dark | Up | 29.5 | 157.7 | Low | 08:56:23 - 09:25:14 | 1590 |
| La Pine/Gilchrist | 09:10:49 | -23.5 | Dark | Up | 29.7 | 157.6 | Low | 08:56:24 - 09:25:15 | 1576 |
| Niwot | 09:09:42 | -21.6 | Dark | Up | 35.9 | 175.4 | Up | 08:55:16 - 09:24:07 | 1571 |
| North Lake | 09:10:47 | -23.8 | Dark | Up | 30.2 | 158.2 | Up | 08:56:21 - 09:25:12 | 1558 |
| Paisley | 09:10:46 | -24.2 | Dark | Up | 30.8 | 158.4 | Up | 08:56:20 - 09:25:11 | 1528 |
| Chiloquin | 09:10:51 | -24.6 | Dark | Up | 30.6 | 157.0 | Up | 08:56:26 - 09:25:17 | 1499 |
| Lakeview | 09:10:46 | -24.7 | Dark | Up | 31.3 | 158.5 | Up | 08:56:20 - 09:25:11 | 1498 |
| Klamath Falls | 09:10:51 | -24.9 | Dark | Up | 30.9 | 157.0 | Up | 08:56:26 - 09:25:17 | 1477 |
| Tulelake | 09:10:50 | -25.1 | Dark | Up | 31.3 | 157.3 | Up | 08:56:25 - 09:25:16 | 1465 |
| Cedarville | 09:10:46 | -25.2 | Dark | Up | 32.0 | 158.6 | Up | 08:56:20 - 09:25:11 | 1457 |
| Fall River/Burney | 09:10:51 | -26.0 | Dark | Up | 32.1 | 157.1 | Up | 08:56:26 - 09:25:17 | 1405 |
| Susanville | 09:10:49 | -26.4 | Dark | Up | 32.9 | 157.8 | Up | 08:56:23 - 09:25:14 | 1374 |
| Gimple | 09:10:49 | -26.7 | Dark | Up | 33.1 | 157.5 | Up | 08:56:24 - 09:25:15 | 1352 |
| Greenville | 09:10:50 | -26.7 | Dark | Up | 33.1 | 157.4 | Up | 08:56:24 - 09:25:15 | 1351 |
| Quincy | 09:10:50 | -26.9 | Dark | Up | 33.3 | 157.4 | Up | 08:56:24 - 09:25:15 | 1337 |
| Portola | 09:10:48 | -26.9 | Dark | Up | 33.5 | 157.8 | Up | 08:56:23 - 09:25:14 | 1336 |
| Reno | 09:10:46 | -27.0 | Dark | Up | 34.0 | 158.5 | Up | 08:56:20 - 09:25:11 | 1328 |
| Carson City | 09:10:46 | -27.4 | Dark | Up | 34.3 | 158.4 | Up | 08:56:20 - 09:25:11 | 1303 |
| Yerington | 09:10:43 | -27.4 | Dark | Up | 34.7 | 159.1 | Up | 08:56:18 - 09:25:09 | 1300 |
| Gardnerville | 09:10:46 | -27.6 | Dark | Up | 34.5 | 158.4 | Up | 08:56:20 - 09:25:11 | 1287 |
| Hawthorne | 09:10:42 | -27.7 | Dark | Up | 35.2 | 159.6 | Up | 08:56:16 - 09:25:07 | 1276 |
| Tonopah | 09:10:35 | -27.7 | Dark | Up | 36.0 | 161.1 | Up | 08:56:10 - 09:25:01 | 1266 |
| Lee Vining | 09:10:44 | -28.3 | Dark | Up | 35.6 | 158.9 | Up | 08:56:18 - 09:25:09 | 1228 |
| Bishop | 09:10:41 | -28.7 | Dark | Up | 36.4 | 159.5 | Up | 08:56:16 - 09:25:07 | 1197 |
| Beatty | 09:10:34 | -28.6 | Dark | Up | 37.2 | 161.3 | Up | 08:56:09 - 09:25:00 | 1190 |
| Indian Springs | 09:10:29 | -28.6 | Dark | Up | 37.8 | 162.5 | Up | 08:56:04 - 09:24:55 | 1183 |
| Henderson | 09:10:27 | -28.8 | Dark | Up | 38.5 | 163.2 | Up | 08:56:01 - 09:24:52 | 1155 |
| Lone Pine | 09:10:40 | -29.3 | Dark | Up | 37.2 | 159.7 | Up | 08:56:14 - 09:25:05 | 1147 |
| Patrick | 09:10:21 | -29.0 | Dark | Up | 39.3 | 164.4 | Up | 08:55:56 - 09:24:47 | 1126 |
| DCO | 09:10:18 | -29.0 | Dark | Up | 39.8 | 165.2 | Up | 08:55:53 - 09:24:44 | 1114 |
| Searchlight/Boulder City | 09:10:26 | -29.3 | Dark | Up | 39.1 | 163.1 | Up | 08:56:01 - 09:24:52 | 1114 |
| Kingman/Dolan Springs | 09:10:23 | -29.3 | Dark | Up | 39.5 | 164.1 | Up | 08:55:57 - 09:24:48 | 1107 |
| Laughlin/Bullhead City | 09:10:25 | -29.5 | Dark | Up | 39.4 | 163.5 | Up | 08:55:59 - 09:24:50 | 1097 |
| Mohave Valley | 09:10:25 | -29.7 | Dark | Up | 39.7 | 163.4 | Up | 08:55:59 - 09:24:50 | 1077 |
| Lake Havasu City | 09:10:24 | -30.0 | Dark | Up | 40.1 | 163.6 | Up | 08:55:59 - 09:24:50 | 1051 |
| Parker | 09:10:24 | -30.3 | Dark | Up | 40.5 | 163.6 | Up | 08:55:58 - 09:24:49 | 1024 |
| CPSLO | 09:10:52 | -31.2 | Dark | Up | 37.6 | 156.4 | Up | 08:56:27 - 09:25:18 | 1007 |
| Blythe | 09:10:25 | -30.9 | Dark | Up | 40.9 | 163.1 | Up | 08:56:00 - 09:24:51 | 980 |
| Idyllwild | 09:10:35 | -31.5 | Dark | Up | 40.3 | 160.5 | Up | 08:56:10 - 09:25:01 | 954 |
| Wildwood | 09:10:44 | -31.8 | Dark | Up | 39.4 | 158.4 | Up | 08:56:18 - 09:25:09 | 950 |
| Calipatria | 09:10:30 | -31.7 | Dark | Up | 41.1 | 161.8 | Up | 08:56:05 - 09:24:56 | 927 |
| Yuma | 09:10:26 | -31.7 | Dark | Up | 41.8 | 162.8 | Up | 08:56:00 - 09:24:51 | 908 |
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 503858, (2018/05/25 09:09UT) Object RA Dec mag sep mel Antares 16:29:24.4 -26:25:56 0.9 32.17 56 Nunki 18:55:15.9 -26:17:49 2.0 13.22 88 PPM 234707 18:33:39.1 -14:51:13 6.1 1.16 83 PPM 234768 18:36:12.4 -13:50:02 8.3 0.03 84 503858 18:36:07.8 -13:51:29 16.2 84 Positions are for J2000
Event circumstances last updated at 2017/12/02 17:34:48 UT
Marc W. Buie, Southwest Research Institute