メタデータ
| 項目 |
値 |
| Designation |
C/2017 K6 (Jacques) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2018-01-03T03:16:30.506880Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:34Z |
| Obs used |
475 |
| NEO |
- |
| M1 |
12.100 |
| K1 |
6.250 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2018-02-05.0000000 |
| e |
0.99822114 |
| q (au) |
2.002756 |
| a (au) |
1125.867222 |
| i (deg) |
57.251183 |
| Ω (om, deg) |
85.054187 |
| ω (w, deg) |
303.838384 |
| M (ma, deg) |
0.000857 |
等級
散乱 + 全体線形
$$
M_a = (10.455 + 4.414\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.455 |
| n |
4.414 |
| gf |
1.000 |
| gb |
-0.891 |
| k |
0.984 |
| 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
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 2017-05-29 |
2017-09-21 |
-1.7758 |
+1.105 |
| 2017-09-21 |
2017-12-30 |
+16.2248 |
-5.376 |
| 2018-01-05 |
2019-02-14 |
+1.6842 |
-1.364 |
log10 r = log10(太陽距離/AU)、Δ = 地球距離(AU)
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
13:29:53.62 |
+53:08:20.6 |
HIP 65802 |
5.83 |
| 2026-07-29 12:00 |
13:29:56.09 |
+53:07:04.8 |
HIP 65802 |
6.75 |
| 2026-07-30 00:00 |
13:29:58.62 |
+53:05:49.0 |
HIP 65802 |
7.79 |
| 2026-07-30 12:00 |
13:30:01.21 |
+53:04:33.3 |
HIP 65802 |
8.91 |
| 2026-07-31 00:00 |
13:30:03.87 |
+53:03:17.6 |
HIP 65802 |
10.09 |
| 2026-07-31 12:00 |
13:30:06.59 |
+53:02:02.0 |
HIP 65802 |
11.30 |
| 2026-08-01 00:00 |
13:30:09.37 |
+53:00:46.5 |
HIP 65802 |
12.54 |
| 2026-08-01 12:00 |
13:30:12.22 |
+52:59:31.0 |
HIP 65802 |
13.80 |
| 2026-08-02 00:00 |
13:30:15.13 |
+52:58:15.6 |
HIP 65802 |
15.08 |
| 2026-08-02 12:00 |
13:30:18.10 |
+52:57:00.2 |
HIP 65802 |
16.37 |
| 2026-08-03 00:00 |
13:30:21.13 |
+52:55:45.0 |
HIP 65802 |
17.68 |
| 2026-08-03 12:00 |
13:30:24.22 |
+52:54:29.8 |
HIP 65802 |
18.98 |
| 2026-08-04 00:00 |
13:30:27.38 |
+52:53:14.7 |
HIP 65802 |
20.30 |
| 2026-08-04 12:00 |
13:30:30.59 |
+52:51:59.7 |
HIP 65802 |
21.62 |
| 2026-08-05 00:00 |
13:30:33.87 |
+52:50:44.8 |
HIP 65802 |
22.95 |
| 2026-08-05 12:00 |
13:30:37.21 |
+52:49:30.0 |
HIP 65678 |
24.28 |
| 2026-08-06 00:00 |
13:30:40.60 |
+52:48:15.3 |
HIP 65678 |
24.58 |
| 2026-08-06 12:00 |
13:30:44.06 |
+52:47:00.7 |
HIP 65678 |
24.96 |
| 2026-08-07 00:00 |
13:30:47.58 |
+52:45:46.2 |
HIP 65678 |
25.42 |
| 2026-08-07 12:00 |
13:30:51.16 |
+52:44:31.8 |
HIP 65678 |
25.95 |
| 2026-08-08 00:00 |
13:30:54.80 |
+52:43:17.6 |
HIP 65678 |
26.54 |
| 2026-08-08 12:00 |
13:30:58.49 |
+52:42:03.5 |
HIP 65678 |
27.20 |
| 2026-08-09 00:00 |
13:31:02.25 |
+52:40:49.5 |
HIP 65678 |
27.92 |
| 2026-08-09 12:00 |
13:31:06.06 |
+52:39:35.6 |
HIP 65678 |
28.69 |
| 2026-08-10 00:00 |
13:31:09.94 |
+52:38:21.9 |
HIP 65678 |
29.52 |
| 2026-08-10 12:00 |
13:31:13.87 |
+52:37:08.3 |
HIP 65678 |
30.39 |
| 2026-08-11 00:00 |
13:31:17.86 |
+52:35:54.9 |
HIP 65678 |
31.30 |
| 2026-08-11 12:00 |
13:31:21.91 |
+52:34:41.6 |
HIP 65678 |
32.26 |
| 2026-08-12 00:00 |
13:31:26.01 |
+52:33:28.5 |
HIP 66061 |
32.73 |
| 2026-08-12 12:00 |
13:31:30.17 |
+52:32:15.6 |
HIP 66061 |
31.37 |
| 2026-08-13 00:00 |
13:31:34.39 |
+52:31:02.8 |
HIP 66061 |
30.02 |
| 2026-08-13 12:00 |
13:31:38.66 |
+52:29:50.2 |
HIP 66061 |
28.67 |
| 2026-08-14 00:00 |
13:31:42.99 |
+52:28:37.7 |
HIP 66061 |
27.32 |
| 2026-08-14 12:00 |
13:31:47.38 |
+52:27:25.5 |
HIP 66061 |
25.97 |
| 2026-08-15 00:00 |
13:31:51.82 |
+52:26:13.4 |
HIP 66061 |
24.63 |
| 2026-08-15 12:00 |
13:31:56.31 |
+52:25:01.5 |
HIP 66061 |
23.30 |
| 2026-08-16 00:00 |
13:32:00.86 |
+52:23:49.8 |
HIP 66061 |
21.97 |
| 2026-08-16 12:00 |
13:32:05.47 |
+52:22:38.3 |
HIP 66061 |
20.65 |
| 2026-08-17 00:00 |
13:32:10.13 |
+52:21:27.0 |
HIP 66061 |
19.34 |
| 2026-08-17 12:00 |
13:32:14.84 |
+52:20:15.9 |
HIP 66061 |
18.04 |
| 2026-08-18 00:00 |
13:32:19.60 |
+52:19:05.0 |
HIP 66061 |
16.76 |
| 2026-08-18 12:00 |
13:32:24.42 |
+52:17:54.4 |
HIP 66061 |
15.50 |
| 2026-08-19 00:00 |
13:32:29.29 |
+52:16:43.9 |
HIP 66061 |
14.27 |