メタデータ
| 項目 |
値 |
| Designation |
C/2017 U4 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2018-09-25T16:38:00.893760Z |
| Orbit solution date (soln_date, UTC) |
2023-02-13T23:12:42Z |
| Obs used |
85 |
| NEO |
- |
| M1 |
7.100 |
| K1 |
10.750 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2018-01-03.0000000 |
| e |
1.00304382 |
| q (au) |
7.724158 |
| a (au) |
-2537.649728 |
| i (deg) |
158.225721 |
| Ω (om, deg) |
245.952559 |
| ω (w, deg) |
159.177100 |
| M (ma, deg) |
-0.002049 |
等級
散乱 + 全体線形
$$
M_a = (2.306 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
2.306 |
| n |
6.000 |
| gf |
0.993 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
9.974 |
| パラメータ |
記号 |
範囲 |
説明 |
| 太陽・地球距離が1 AUのときの絶対等級 |
H0 |
-5 to 20 |
彗星の固有の明るさ |
| 測光スロープパラメータ |
n |
2 to 6 |
太陽距離に対する明るさ変化率 |
| 前方散乱非対称係数 |
gf |
0.8 to 1 |
前方散乱の強さ |
| 後方散乱非対称係数 |
gb |
-1 to -0.5 |
後方散乱の強さ |
| 分配係数 |
k |
0.8 to 1 |
前方/後方散乱の寄与比 |
| ダスト/ガス明るさ比 |
δ90 |
1 to 10 |
ダスト散乱とガス放射の相対寄与 |
参考: EPSC-DPS2025-160
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
00:15:51.96 |
-21:03:16.6 |
HIP 1147 |
22.89 |
| 2026-06-01 12:00 |
00:15:53.18 |
-21:03:49.4 |
HIP 1147 |
22.96 |
| 2026-06-02 00:00 |
00:15:54.36 |
-21:04:22.5 |
HIP 1147 |
23.03 |
| 2026-06-02 12:00 |
00:15:55.49 |
-21:04:56.1 |
HIP 1147 |
23.11 |
| 2026-06-03 00:00 |
00:15:56.57 |
-21:05:30.1 |
HIP 1147 |
23.19 |
| 2026-06-03 12:00 |
00:15:57.59 |
-21:06:04.5 |
HIP 1147 |
23.27 |
| 2026-06-04 00:00 |
00:15:58.57 |
-21:06:39.3 |
HIP 1147 |
23.36 |
| 2026-06-04 12:00 |
00:15:59.50 |
-21:07:14.6 |
HIP 1147 |
23.44 |
| 2026-06-05 00:00 |
00:16:00.38 |
-21:07:50.3 |
HIP 1147 |
23.54 |
| 2026-06-05 12:00 |
00:16:01.20 |
-21:08:26.4 |
HIP 1147 |
23.63 |
| 2026-06-06 00:00 |
00:16:01.98 |
-21:09:03.0 |
HIP 1147 |
23.73 |
| 2026-06-06 12:00 |
00:16:02.70 |
-21:09:40.0 |
HIP 1147 |
23.84 |
| 2026-06-07 00:00 |
00:16:03.37 |
-21:10:17.4 |
HIP 1147 |
23.95 |
| 2026-06-07 12:00 |
00:16:03.99 |
-21:10:55.2 |
HIP 1147 |
24.06 |
| 2026-06-08 00:00 |
00:16:04.56 |
-21:11:33.4 |
HIP 1147 |
24.18 |
| 2026-06-08 12:00 |
00:16:05.08 |
-21:12:12.1 |
HIP 1147 |
24.30 |
| 2026-06-09 00:00 |
00:16:05.54 |
-21:12:51.2 |
HIP 1323 |
24.34 |
| 2026-06-09 12:00 |
00:16:05.95 |
-21:13:30.7 |
HIP 1323 |
23.68 |
| 2026-06-10 00:00 |
00:16:06.31 |
-21:14:10.6 |
HIP 1323 |
23.02 |
| 2026-06-10 12:00 |
00:16:06.61 |
-21:14:50.9 |
HIP 1323 |
22.36 |
| 2026-06-11 00:00 |
00:16:06.86 |
-21:15:31.6 |
HIP 1323 |
21.70 |
| 2026-06-11 12:00 |
00:16:07.06 |
-21:16:12.8 |
HIP 1323 |
21.04 |
| 2026-06-12 00:00 |
00:16:07.21 |
-21:16:54.4 |
HIP 1323 |
20.38 |
| 2026-06-12 12:00 |
00:16:07.30 |
-21:17:36.3 |
HIP 1323 |
19.71 |
| 2026-06-13 00:00 |
00:16:07.33 |
-21:18:18.7 |
HIP 1323 |
19.05 |
| 2026-06-13 12:00 |
00:16:07.31 |
-21:19:01.5 |
HIP 1323 |
18.39 |
| 2026-06-14 00:00 |
00:16:07.24 |
-21:19:44.7 |
HIP 1323 |
17.74 |
| 2026-06-14 12:00 |
00:16:07.11 |
-21:20:28.3 |
HIP 1323 |
17.08 |
| 2026-06-15 00:00 |
00:16:06.93 |
-21:21:12.2 |
HIP 1323 |
16.44 |
| 2026-06-15 12:00 |
00:16:06.69 |
-21:21:56.6 |
HIP 1323 |
15.80 |
| 2026-06-16 00:00 |
00:16:06.40 |
-21:22:41.4 |
HIP 1323 |
15.17 |
| 2026-06-16 12:00 |
00:16:06.05 |
-21:23:26.6 |
HIP 1323 |
14.55 |
| 2026-06-17 00:00 |
00:16:05.64 |
-21:24:12.1 |
HIP 1323 |
13.95 |
| 2026-06-17 12:00 |
00:16:05.18 |
-21:24:58.1 |
HIP 1323 |
13.36 |
| 2026-06-18 00:00 |
00:16:04.67 |
-21:25:44.4 |
HIP 1323 |
12.80 |
| 2026-06-18 12:00 |
00:16:04.10 |
-21:26:31.2 |
HIP 1323 |
12.27 |
| 2026-06-19 00:00 |
00:16:03.47 |
-21:27:18.3 |
HIP 1323 |
11.77 |
| 2026-06-19 12:00 |
00:16:02.78 |
-21:28:05.8 |
HIP 1323 |
11.31 |
| 2026-06-20 00:00 |
00:16:02.04 |
-21:28:53.6 |
HIP 1323 |
10.89 |
| 2026-06-20 12:00 |
00:16:01.25 |
-21:29:41.9 |
HIP 1323 |
10.53 |
| 2026-06-21 00:00 |
00:16:00.39 |
-21:30:30.5 |
HIP 1323 |
10.23 |
| 2026-06-21 12:00 |
00:15:59.49 |
-21:31:19.4 |
HIP 1323 |
10.00 |
| 2026-06-22 00:00 |
00:15:58.52 |
-21:32:08.8 |
HIP 1323 |
9.84 |