メタデータ
| 項目 |
値 |
| Designation |
C/2009 K2 (Catalina) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2010-02-07T11:38:37.547520Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:31Z |
| Obs used |
665 |
| NEO |
- |
| M1 |
11.800 |
| K1 |
7.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2009-08-14.0000000 |
| e |
0.99777882 |
| q (au) |
3.246176 |
| a (au) |
1461.466569 |
| i (deg) |
66.821915 |
| Ω (om, deg) |
123.805511 |
| ω (w, deg) |
147.693496 |
| M (ma, deg) |
359.996869 |
等級
散乱 + 全体線形
$$
M_a = (8.341 + 4.485\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
8.341 |
| n |
4.485 |
| gf |
1.000 |
| gb |
-0.989 |
| 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) |
| 2026-06-01 00:00 |
05:29:24.04 |
-34:13:30.9 |
HIP 25709 |
17.41 |
| 2026-06-01 12:00 |
05:29:28.36 |
-34:13:16.9 |
HIP 25709 |
17.67 |
| 2026-06-02 00:00 |
05:29:32.68 |
-34:13:03.3 |
HIP 25709 |
17.96 |
| 2026-06-02 12:00 |
05:29:37.01 |
-34:12:50.0 |
HIP 25709 |
18.29 |
| 2026-06-03 00:00 |
05:29:41.34 |
-34:12:37.1 |
HIP 25709 |
18.65 |
| 2026-06-03 12:00 |
05:29:45.68 |
-34:12:24.6 |
HIP 25709 |
19.05 |
| 2026-06-04 00:00 |
05:29:50.03 |
-34:12:12.4 |
HIP 25709 |
19.47 |
| 2026-06-04 12:00 |
05:29:54.38 |
-34:12:00.5 |
HIP 25709 |
19.92 |
| 2026-06-05 00:00 |
05:29:58.74 |
-34:11:49.0 |
HIP 25709 |
20.40 |
| 2026-06-05 12:00 |
05:30:03.10 |
-34:11:37.9 |
HIP 25709 |
20.91 |
| 2026-06-06 00:00 |
05:30:07.47 |
-34:11:27.1 |
HIP 25709 |
21.43 |
| 2026-06-06 12:00 |
05:30:11.84 |
-34:11:16.6 |
HIP 25709 |
21.98 |
| 2026-06-07 00:00 |
05:30:16.21 |
-34:11:06.6 |
HIP 25709 |
22.55 |
| 2026-06-07 12:00 |
05:30:20.59 |
-34:10:56.8 |
HIP 25709 |
23.13 |
| 2026-06-08 00:00 |
05:30:24.97 |
-34:10:47.5 |
HIP 25709 |
23.74 |
| 2026-06-08 12:00 |
05:30:29.36 |
-34:10:38.5 |
HIP 25709 |
24.35 |
| 2026-06-09 00:00 |
05:30:33.75 |
-34:10:29.8 |
HIP 25709 |
24.98 |
| 2026-06-09 12:00 |
05:30:38.14 |
-34:10:21.6 |
HIP 25709 |
25.63 |
| 2026-06-10 00:00 |
05:30:42.53 |
-34:10:13.6 |
HIP 25709 |
26.28 |
| 2026-06-10 12:00 |
05:30:46.93 |
-34:10:06.1 |
HIP 25709 |
26.95 |
| 2026-06-11 00:00 |
05:30:51.32 |
-34:09:58.9 |
HIP 25709 |
27.62 |
| 2026-06-11 12:00 |
05:30:55.72 |
-34:09:52.0 |
HIP 25709 |
28.31 |
| 2026-06-12 00:00 |
05:31:00.12 |
-34:09:45.6 |
HIP 25709 |
29.00 |
| 2026-06-12 12:00 |
05:31:04.53 |
-34:09:39.4 |
HIP 26035 |
28.54 |
| 2026-06-13 00:00 |
05:31:08.93 |
-34:09:33.7 |
HIP 26035 |
27.70 |
| 2026-06-13 12:00 |
05:31:13.33 |
-34:09:28.3 |
HIP 26035 |
26.87 |
| 2026-06-14 00:00 |
05:31:17.73 |
-34:09:23.3 |
HIP 26035 |
26.04 |
| 2026-06-14 12:00 |
05:31:22.14 |
-34:09:18.6 |
HIP 26035 |
25.21 |
| 2026-06-15 00:00 |
05:31:26.54 |
-34:09:14.3 |
HIP 26035 |
24.39 |
| 2026-06-15 12:00 |
05:31:30.94 |
-34:09:10.4 |
HIP 26035 |
23.57 |
| 2026-06-16 00:00 |
05:31:35.35 |
-34:09:06.8 |
HIP 26035 |
22.76 |
| 2026-06-16 12:00 |
05:31:39.75 |
-34:09:03.6 |
HIP 26035 |
21.95 |
| 2026-06-17 00:00 |
05:31:44.14 |
-34:09:00.7 |
HIP 26035 |
21.15 |
| 2026-06-17 12:00 |
05:31:48.54 |
-34:08:58.2 |
HIP 26035 |
20.35 |
| 2026-06-18 00:00 |
05:31:52.94 |
-34:08:56.1 |
HIP 26035 |
19.56 |
| 2026-06-18 12:00 |
05:31:57.33 |
-34:08:54.3 |
HIP 26035 |
18.79 |
| 2026-06-19 00:00 |
05:32:01.72 |
-34:08:52.9 |
HIP 26035 |
18.02 |
| 2026-06-19 12:00 |
05:32:06.11 |
-34:08:51.9 |
HIP 26035 |
17.26 |
| 2026-06-20 00:00 |
05:32:10.49 |
-34:08:51.2 |
HIP 26035 |
16.51 |
| 2026-06-20 12:00 |
05:32:14.87 |
-34:08:50.9 |
HIP 26035 |
15.78 |
| 2026-06-21 00:00 |
05:32:19.25 |
-34:08:51.0 |
HIP 26035 |
15.06 |
| 2026-06-21 12:00 |
05:32:23.62 |
-34:08:51.4 |
HIP 26035 |
14.36 |
| 2026-06-22 00:00 |
05:32:27.99 |
-34:08:52.1 |
HIP 26035 |
13.68 |