C/2017 U5 (PANSTARRS)
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) |
| 2026-02-03 00:00 |
13:35:50.57 |
+02:16:06.6 |
HIP 66349 |
24.82 |
| 2026-02-03 12:00 |
13:35:49.60 |
+02:16:41.0 |
HIP 66349 |
24.26 |
| 2026-02-04 00:00 |
13:35:48.58 |
+02:17:15.7 |
HIP 66349 |
23.70 |
| 2026-02-04 12:00 |
13:35:47.49 |
+02:17:50.6 |
HIP 66349 |
23.14 |
| 2026-02-05 00:00 |
13:35:46.34 |
+02:18:25.9 |
HIP 66349 |
22.58 |
| 2026-02-05 12:00 |
13:35:45.14 |
+02:19:01.4 |
HIP 66349 |
22.02 |
| 2026-02-06 00:00 |
13:35:43.87 |
+02:19:37.3 |
HIP 66349 |
21.46 |
| 2026-02-06 12:00 |
13:35:42.54 |
+02:20:13.4 |
HIP 66349 |
20.91 |
| 2026-02-07 00:00 |
13:35:41.15 |
+02:20:49.9 |
HIP 66349 |
20.37 |
| 2026-02-07 12:00 |
13:35:39.70 |
+02:21:26.6 |
HIP 66349 |
19.83 |
| 2026-02-08 00:00 |
13:35:38.19 |
+02:22:03.6 |
HIP 66349 |
19.30 |
| 2026-02-08 12:00 |
13:35:36.62 |
+02:22:40.8 |
HIP 66349 |
18.79 |
| 2026-02-09 00:00 |
13:35:34.99 |
+02:23:18.4 |
HIP 66349 |
18.29 |
| 2026-02-09 12:00 |
13:35:33.30 |
+02:23:56.2 |
HIP 66349 |
17.81 |
| 2026-02-10 00:00 |
13:35:31.55 |
+02:24:34.3 |
HIP 66349 |
17.34 |
| 2026-02-10 12:00 |
13:35:29.74 |
+02:25:12.7 |
HIP 66349 |
16.90 |
| 2026-02-11 00:00 |
13:35:27.88 |
+02:25:51.3 |
HIP 66349 |
16.49 |
| 2026-02-11 12:00 |
13:35:25.95 |
+02:26:30.2 |
HIP 66349 |
16.11 |
| 2026-02-12 00:00 |
13:35:23.96 |
+02:27:09.4 |
HIP 66349 |
15.77 |
| 2026-02-12 12:00 |
13:35:21.92 |
+02:27:48.8 |
HIP 66349 |
15.47 |
| 2026-02-13 00:00 |
13:35:19.82 |
+02:28:28.4 |
HIP 66349 |
15.21 |
| 2026-02-13 12:00 |
13:35:17.66 |
+02:29:08.3 |
HIP 66349 |
15.00 |
| 2026-02-14 00:00 |
13:35:15.44 |
+02:29:48.5 |
HIP 66349 |
14.84 |
| 2026-02-14 12:00 |
13:35:13.16 |
+02:30:28.9 |
HIP 66349 |
14.74 |
| 2026-02-15 00:00 |
13:35:10.83 |
+02:31:09.5 |
HIP 66349 |
14.70 |
| 2026-02-15 12:00 |
13:35:08.44 |
+02:31:50.4 |
HIP 66349 |
14.72 |
| 2026-02-16 00:00 |
13:35:05.99 |
+02:32:31.5 |
HIP 66349 |
14.81 |
| 2026-02-16 12:00 |
13:35:03.48 |
+02:33:12.8 |
HIP 66349 |
14.96 |
| 2026-02-17 00:00 |
13:35:00.92 |
+02:33:54.3 |
HIP 66349 |
15.18 |
| 2026-02-17 12:00 |
13:34:58.31 |
+02:34:36.1 |
HIP 66349 |
15.47 |
| 2026-02-18 00:00 |
13:34:55.63 |
+02:35:18.1 |
HIP 66349 |
15.82 |
| 2026-02-18 12:00 |
13:34:52.90 |
+02:36:00.3 |
HIP 66349 |
16.24 |
| 2026-02-19 00:00 |
13:34:50.12 |
+02:36:42.7 |
HIP 66349 |
16.71 |
| 2026-02-19 12:00 |
13:34:47.28 |
+02:37:25.3 |
HIP 66349 |
17.24 |
| 2026-02-20 00:00 |
13:34:44.38 |
+02:38:08.1 |
HIP 66349 |
17.82 |
| 2026-02-20 12:00 |
13:34:41.44 |
+02:38:51.1 |
HIP 66349 |
18.46 |
| 2026-02-21 00:00 |
13:34:38.43 |
+02:39:34.3 |
HIP 66349 |
19.14 |
| 2026-02-21 12:00 |
13:34:35.38 |
+02:40:17.7 |
HIP 66349 |
19.86 |
| 2026-02-22 00:00 |
13:34:32.27 |
+02:41:01.2 |
HIP 66349 |
20.63 |
| 2026-02-22 12:00 |
13:34:29.11 |
+02:41:45.0 |
HIP 66349 |
21.44 |
| 2026-02-23 00:00 |
13:34:25.89 |
+02:42:28.9 |
HIP 66349 |
22.28 |
| 2026-02-23 12:00 |
13:34:22.63 |
+02:43:13.0 |
HIP 66349 |
23.15 |
| 2026-02-24 00:00 |
13:34:19.31 |
+02:43:57.2 |
HIP 66349 |
24.06 |