メタデータ
| 項目 |
値 |
| Designation |
C/2017 U5 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-12-19T02:35:57.655680Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:37Z |
| Obs used |
92 |
| NEO |
- |
| M1 |
11.800 |
| K1 |
10.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2017-11-25.0000000 |
| e |
0.74456954 |
| q (au) |
4.326737 |
| a (au) |
16.939001 |
| i (deg) |
18.956551 |
| Ω (om, deg) |
163.115368 |
| ω (w, deg) |
262.150770 |
| M (ma, deg) |
359.659169 |
等級
散乱 + 全体線形
$$
M_a = (14.300 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
14.300 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
10.000 |
| 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) |
| 2026-03-26 00:00 |
13:29:41.79 |
+03:30:43.4 |
HIP 65791 |
22.68 |
| 2026-03-26 12:00 |
13:29:36.17 |
+03:31:30.0 |
HIP 65791 |
21.53 |
| 2026-03-27 00:00 |
13:29:30.53 |
+03:32:16.4 |
HIP 65791 |
20.45 |
| 2026-03-27 12:00 |
13:29:24.87 |
+03:33:02.8 |
HIP 65791 |
19.44 |
| 2026-03-28 00:00 |
13:29:19.19 |
+03:33:49.0 |
HIP 65791 |
18.52 |
| 2026-03-28 12:00 |
13:29:13.49 |
+03:34:35.1 |
HIP 65791 |
17.70 |
| 2026-03-29 00:00 |
13:29:07.77 |
+03:35:21.1 |
HIP 65791 |
17.00 |
| 2026-03-29 12:00 |
13:29:02.04 |
+03:36:07.0 |
HIP 65791 |
16.43 |
| 2026-03-30 00:00 |
13:28:56.29 |
+03:36:52.7 |
HIP 65791 |
16.00 |
| 2026-03-30 12:00 |
13:28:50.52 |
+03:37:38.3 |
HIP 65791 |
15.74 |
| 2026-03-31 00:00 |
13:28:44.74 |
+03:38:23.8 |
HIP 65791 |
15.65 |
| 2026-03-31 12:00 |
13:28:38.94 |
+03:39:09.2 |
HIP 65791 |
15.73 |
| 2026-04-01 00:00 |
13:28:33.13 |
+03:39:54.4 |
HIP 65791 |
15.98 |
| 2026-04-01 12:00 |
13:28:27.30 |
+03:40:39.5 |
HIP 65660 |
15.86 |
| 2026-04-02 00:00 |
13:28:21.46 |
+03:41:24.4 |
HIP 65660 |
14.34 |
| 2026-04-02 12:00 |
13:28:15.60 |
+03:42:09.1 |
HIP 65660 |
12.85 |
| 2026-04-03 00:00 |
13:28:09.74 |
+03:42:53.7 |
HIP 65660 |
11.40 |
| 2026-04-03 12:00 |
13:28:03.86 |
+03:43:38.2 |
HIP 65660 |
10.01 |
| 2026-04-04 00:00 |
13:27:57.97 |
+03:44:22.5 |
HIP 65660 |
8.71 |
| 2026-04-04 12:00 |
13:27:52.07 |
+03:45:06.6 |
HIP 65660 |
7.56 |
| 2026-04-05 00:00 |
13:27:46.17 |
+03:45:50.5 |
HIP 65660 |
6.61 |
| 2026-04-05 12:00 |
13:27:40.25 |
+03:46:34.3 |
HIP 65660 |
5.98 |
| 2026-04-06 00:00 |
13:27:34.32 |
+03:47:17.9 |
HIP 65660 |
5.77 |
| 2026-04-06 12:00 |
13:27:28.39 |
+03:48:01.3 |
HIP 65660 |
6.02 |
| 2026-04-07 00:00 |
13:27:22.44 |
+03:48:44.5 |
HIP 65660 |
6.69 |
| 2026-04-07 12:00 |
13:27:16.49 |
+03:49:27.5 |
HIP 65660 |
7.66 |
| 2026-04-08 00:00 |
13:27:10.54 |
+03:50:10.4 |
HIP 65660 |
8.84 |
| 2026-04-08 12:00 |
13:27:04.58 |
+03:50:53.0 |
HIP 65660 |
10.15 |
| 2026-04-09 00:00 |
13:26:58.61 |
+03:51:35.4 |
HIP 65660 |
11.55 |
| 2026-04-09 12:00 |
13:26:52.64 |
+03:52:17.7 |
HIP 65660 |
13.01 |
| 2026-04-10 00:00 |
13:26:46.67 |
+03:52:59.7 |
HIP 65660 |
14.51 |
| 2026-04-10 12:00 |
13:26:40.69 |
+03:53:41.5 |
HIP 65660 |
16.04 |
| 2026-04-11 00:00 |
13:26:34.71 |
+03:54:23.0 |
HIP 65660 |
17.59 |
| 2026-04-11 12:00 |
13:26:28.73 |
+03:55:04.4 |
HIP 65660 |
19.15 |
| 2026-04-12 00:00 |
13:26:22.74 |
+03:55:45.5 |
HIP 65660 |
20.73 |
| 2026-04-12 12:00 |
13:26:16.76 |
+03:56:26.4 |
HIP 65660 |
22.32 |
| 2026-04-13 00:00 |
13:26:10.78 |
+03:57:07.1 |
HIP 65660 |
23.91 |
| 2026-04-13 12:00 |
13:26:04.79 |
+03:57:47.5 |
HIP 65660 |
25.51 |
| 2026-04-14 00:00 |
13:25:58.81 |
+03:58:27.7 |
HIP 65660 |
27.11 |
| 2026-04-14 12:00 |
13:25:52.83 |
+03:59:07.7 |
HIP 65660 |
28.71 |
| 2026-04-15 00:00 |
13:25:46.85 |
+03:59:47.4 |
HIP 65442 |
29.14 |
| 2026-04-15 12:00 |
13:25:40.88 |
+04:00:26.8 |
HIP 65442 |
27.78 |
| 2026-04-16 00:00 |
13:25:34.91 |
+04:01:06.0 |
HIP 65442 |
26.46 |