C/1999 K2 (Ferris)
メタデータ
| 項目 |
値 |
| Designation |
C/1999 K2 (Ferris) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1999-04-10T12:51:40.688640Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:30:00Z |
| Obs used |
101 |
| NEO |
- |
| M1 |
7.000 |
| 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) |
1999-06-24.0000000 |
| e |
0.96579603 |
| q (au) |
5.290256 |
| a (au) |
154.667896 |
| i (deg) |
82.190925 |
| Ω (om, deg) |
300.318118 |
| ω (w, deg) |
4.570397 |
| M (ma, deg) |
0.038155 |
等級
散乱 + 全体線形
$$
M_a = (12.566 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
12.566 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.664 |
| k |
0.800 |
| 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 |
08:24:56.11 |
+53:50:13.2 |
HIP 41267 |
6.01 |
| 2026-02-03 12:00 |
08:24:51.55 |
+53:50:14.1 |
HIP 41267 |
6.25 |
| 2026-02-04 00:00 |
08:24:46.99 |
+53:50:14.8 |
HIP 41267 |
6.55 |
| 2026-02-04 12:00 |
08:24:42.45 |
+53:50:15.2 |
HIP 41267 |
6.91 |
| 2026-02-05 00:00 |
08:24:37.91 |
+53:50:15.4 |
HIP 41267 |
7.32 |
| 2026-02-05 12:00 |
08:24:33.38 |
+53:50:15.4 |
HIP 41267 |
7.76 |
| 2026-02-06 00:00 |
08:24:28.86 |
+53:50:15.1 |
HIP 41267 |
8.23 |
| 2026-02-06 12:00 |
08:24:24.35 |
+53:50:14.7 |
HIP 41267 |
8.73 |
| 2026-02-07 00:00 |
08:24:19.85 |
+53:50:14.0 |
HIP 41267 |
9.26 |
| 2026-02-07 12:00 |
08:24:15.36 |
+53:50:13.0 |
HIP 41267 |
9.80 |
| 2026-02-08 00:00 |
08:24:10.89 |
+53:50:11.9 |
HIP 41267 |
10.35 |
| 2026-02-08 12:00 |
08:24:06.42 |
+53:50:10.5 |
HIP 41267 |
10.92 |
| 2026-02-09 00:00 |
08:24:01.97 |
+53:50:08.9 |
HIP 41267 |
11.50 |
| 2026-02-09 12:00 |
08:23:57.52 |
+53:50:07.0 |
HIP 41267 |
12.08 |
| 2026-02-10 00:00 |
08:23:53.09 |
+53:50:05.0 |
HIP 41267 |
12.67 |
| 2026-02-10 12:00 |
08:23:48.67 |
+53:50:02.7 |
HIP 41267 |
13.27 |
| 2026-02-11 00:00 |
08:23:44.27 |
+53:50:00.1 |
HIP 41267 |
13.88 |
| 2026-02-11 12:00 |
08:23:39.88 |
+53:49:57.4 |
HIP 41267 |
14.48 |
| 2026-02-12 00:00 |
08:23:35.50 |
+53:49:54.4 |
HIP 41267 |
15.09 |
| 2026-02-12 12:00 |
08:23:31.14 |
+53:49:51.2 |
HIP 41267 |
15.71 |
| 2026-02-13 00:00 |
08:23:26.79 |
+53:49:47.8 |
HIP 41267 |
16.32 |
| 2026-02-13 12:00 |
08:23:22.46 |
+53:49:44.1 |
HIP 41267 |
16.94 |
| 2026-02-14 00:00 |
08:23:18.14 |
+53:49:40.3 |
HIP 41267 |
17.56 |
| 2026-02-14 12:00 |
08:23:13.83 |
+53:49:36.1 |
HIP 41267 |
18.17 |
| 2026-02-15 00:00 |
08:23:09.55 |
+53:49:31.8 |
HIP 41267 |
18.79 |
| 2026-02-15 12:00 |
08:23:05.28 |
+53:49:27.3 |
HIP 41267 |
19.41 |
| 2026-02-16 00:00 |
08:23:01.03 |
+53:49:22.5 |
HIP 41267 |
20.03 |
| 2026-02-16 12:00 |
08:22:56.79 |
+53:49:17.5 |
HIP 41267 |
20.65 |
| 2026-02-17 00:00 |
08:22:52.57 |
+53:49:12.2 |
HIP 41267 |
21.26 |
| 2026-02-17 12:00 |
08:22:48.37 |
+53:49:06.8 |
HIP 41267 |
21.88 |
| 2026-02-18 00:00 |
08:22:44.19 |
+53:49:01.1 |
HIP 41267 |
22.50 |
| 2026-02-18 12:00 |
08:22:40.03 |
+53:48:55.2 |
HIP 41267 |
23.11 |
| 2026-02-19 00:00 |
08:22:35.88 |
+53:48:49.1 |
HIP 40878 |
23.62 |
| 2026-02-19 12:00 |
08:22:31.76 |
+53:48:42.7 |
HIP 40878 |
23.07 |
| 2026-02-20 00:00 |
08:22:27.65 |
+53:48:36.1 |
HIP 40878 |
22.53 |
| 2026-02-20 12:00 |
08:22:23.57 |
+53:48:29.3 |
HIP 40878 |
21.99 |
| 2026-02-21 00:00 |
08:22:19.50 |
+53:48:22.3 |
HIP 40878 |
21.46 |
| 2026-02-21 12:00 |
08:22:15.46 |
+53:48:15.1 |
HIP 40878 |
20.92 |
| 2026-02-22 00:00 |
08:22:11.44 |
+53:48:07.7 |
HIP 40878 |
20.40 |
| 2026-02-22 12:00 |
08:22:07.44 |
+53:48:00.0 |
HIP 40878 |
19.87 |
| 2026-02-23 00:00 |
08:22:03.46 |
+53:47:52.1 |
HIP 40878 |
19.36 |
| 2026-02-23 12:00 |
08:21:59.50 |
+53:47:44.0 |
HIP 40878 |
18.84 |
| 2026-02-24 00:00 |
08:21:55.57 |
+53:47:35.7 |
HIP 40878 |
18.33 |