メタデータ
| 項目 |
値 |
| Designation |
C/2017 K5 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2020-03-22T10:59:03.560640Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:35Z |
| Obs used |
116 |
| NEO |
- |
| M1 |
6.600 |
| K1 |
8.750 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2019-02-28.0000000 |
| e |
1.00422212 |
| q (au) |
7.680279 |
| a (au) |
-1819.058463 |
| i (deg) |
82.257758 |
| Ω (om, deg) |
102.375800 |
| ω (w, deg) |
171.715759 |
| M (ma, deg) |
-0.004935 |
等級
散乱 + 全体線形
$$
M_a = (-0.133 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
-0.133 |
| n |
6.000 |
| gf |
0.977 |
| gb |
-0.500 |
| 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
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 2017-05-27 |
2020-03-20 |
+13.4876 |
-12.439 |
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) |
| 2026-06-01 00:00 |
04:01:27.58 |
-67:43:44.4 |
HIP 19154 |
27.85 |
| 2026-06-01 12:00 |
04:01:50.89 |
-67:43:37.1 |
HIP 19154 |
25.64 |
| 2026-06-02 00:00 |
04:02:14.16 |
-67:43:30.6 |
HIP 19154 |
23.43 |
| 2026-06-02 12:00 |
04:02:37.41 |
-67:43:24.9 |
HIP 19154 |
21.23 |
| 2026-06-03 00:00 |
04:03:00.63 |
-67:43:19.9 |
HIP 19154 |
19.03 |
| 2026-06-03 12:00 |
04:03:23.81 |
-67:43:15.7 |
HIP 19154 |
16.83 |
| 2026-06-04 00:00 |
04:03:46.97 |
-67:43:12.3 |
HIP 19154 |
14.63 |
| 2026-06-04 12:00 |
04:04:10.09 |
-67:43:09.6 |
HIP 19154 |
12.44 |
| 2026-06-05 00:00 |
04:04:33.17 |
-67:43:07.7 |
HIP 19154 |
10.26 |
| 2026-06-05 12:00 |
04:04:56.23 |
-67:43:06.5 |
HIP 19154 |
8.08 |
| 2026-06-06 00:00 |
04:05:19.24 |
-67:43:06.1 |
HIP 19154 |
5.91 |
| 2026-06-06 12:00 |
04:05:42.23 |
-67:43:06.5 |
HIP 19154 |
3.76 |
| 2026-06-07 00:00 |
04:06:05.17 |
-67:43:07.7 |
HIP 19154 |
1.70 |
| 2026-06-07 12:00 |
04:06:28.08 |
-67:43:09.6 |
HIP 19154 |
1.07 |
| 2026-06-08 00:00 |
04:06:50.95 |
-67:43:12.2 |
HIP 19154 |
2.97 |
| 2026-06-08 12:00 |
04:07:13.79 |
-67:43:15.6 |
HIP 19154 |
5.09 |
| 2026-06-09 00:00 |
04:07:36.58 |
-67:43:19.8 |
HIP 19154 |
7.23 |
| 2026-06-09 12:00 |
04:07:59.33 |
-67:43:24.8 |
HIP 19154 |
9.38 |
| 2026-06-10 00:00 |
04:08:22.05 |
-67:43:30.5 |
HIP 19154 |
11.53 |
| 2026-06-10 12:00 |
04:08:44.72 |
-67:43:36.9 |
HIP 19154 |
13.68 |
| 2026-06-11 00:00 |
04:09:07.35 |
-67:43:44.1 |
HIP 19154 |
15.83 |
| 2026-06-11 12:00 |
04:09:29.94 |
-67:43:52.1 |
HIP 19594 |
17.47 |
| 2026-06-12 00:00 |
04:09:52.48 |
-67:44:00.9 |
HIP 19594 |
15.89 |
| 2026-06-12 12:00 |
04:10:14.98 |
-67:44:10.4 |
HIP 19594 |
14.48 |
| 2026-06-13 00:00 |
04:10:37.43 |
-67:44:20.6 |
HIP 19594 |
13.27 |
| 2026-06-13 12:00 |
04:10:59.84 |
-67:44:31.6 |
HIP 19594 |
12.34 |
| 2026-06-14 00:00 |
04:11:22.20 |
-67:44:43.3 |
HIP 19594 |
11.73 |
| 2026-06-14 12:00 |
04:11:44.51 |
-67:44:55.9 |
HIP 19594 |
11.51 |
| 2026-06-15 00:00 |
04:12:06.77 |
-67:45:09.1 |
HIP 19594 |
11.70 |
| 2026-06-15 12:00 |
04:12:28.99 |
-67:45:23.1 |
HIP 19594 |
12.27 |
| 2026-06-16 00:00 |
04:12:51.15 |
-67:45:37.9 |
HIP 19594 |
13.16 |
| 2026-06-16 12:00 |
04:13:13.26 |
-67:45:53.4 |
HIP 19594 |
14.33 |
| 2026-06-17 00:00 |
04:13:35.32 |
-67:46:09.6 |
HIP 19594 |
15.71 |
| 2026-06-17 12:00 |
04:13:57.32 |
-67:46:26.6 |
HIP 19594 |
17.23 |
| 2026-06-18 00:00 |
04:14:19.27 |
-67:46:44.3 |
HIP 19594 |
18.88 |
| 2026-06-18 12:00 |
04:14:41.16 |
-67:47:02.7 |
HIP 19594 |
20.61 |
| 2026-06-19 00:00 |
04:15:03.00 |
-67:47:21.9 |
HIP 19594 |
22.41 |
| 2026-06-19 12:00 |
04:15:24.79 |
-67:47:41.8 |
HIP 19594 |
24.26 |
| 2026-06-20 00:00 |
04:15:46.51 |
-67:48:02.5 |
HIP 19594 |
26.15 |
| 2026-06-20 12:00 |
04:16:08.18 |
-67:48:23.8 |
HIP 19594 |
28.07 |
| 2026-06-21 00:00 |
04:16:29.79 |
-67:48:45.9 |
HIP 19594 |
30.01 |
| 2026-06-21 12:00 |
04:16:51.34 |
-67:49:08.7 |
HIP 20295 |
28.65 |
| 2026-06-22 00:00 |
04:17:12.82 |
-67:49:32.3 |
HIP 20295 |
26.81 |