メタデータ
| 項目 |
値 |
| Designation |
C/1973 D1 (Kohoutek) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1973-06-07T04:20:15.918720Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:22Z |
| Obs used |
42 |
| NEO |
- |
| M1 |
9.700 |
| K1 |
18.500 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1973-04-20.0000000 |
| e |
0.99874973 |
| q (au) |
1.382021 |
| a (au) |
1105.378577 |
| i (deg) |
121.598063 |
| Ω (om, deg) |
164.817374 |
| ω (w, deg) |
74.859255 |
| M (ma, deg) |
359.998708 |
等級
散乱 + 全体線形
$$
M_a = (8.986 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
8.986 |
| n |
6.000 |
| gf |
1.000 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
21:56:31.35 |
-63:53:38.6 |
HIP 108493 |
20.27 |
| 2026-05-12 12:00 |
21:56:31.69 |
-63:53:56.3 |
HIP 108493 |
20.04 |
| 2026-05-13 00:00 |
21:56:32.00 |
-63:54:14.2 |
HIP 108493 |
19.81 |
| 2026-05-13 12:00 |
21:56:32.28 |
-63:54:32.1 |
HIP 108493 |
19.58 |
| 2026-05-14 00:00 |
21:56:32.54 |
-63:54:50.0 |
HIP 108493 |
19.36 |
| 2026-05-14 12:00 |
21:56:32.77 |
-63:55:08.0 |
HIP 108493 |
19.14 |
| 2026-05-15 00:00 |
21:56:32.97 |
-63:55:26.1 |
HIP 108493 |
18.92 |
| 2026-05-15 12:00 |
21:56:33.14 |
-63:55:44.2 |
HIP 108493 |
18.71 |
| 2026-05-16 00:00 |
21:56:33.28 |
-63:56:02.3 |
HIP 108493 |
18.50 |
| 2026-05-16 12:00 |
21:56:33.40 |
-63:56:20.5 |
HIP 108493 |
18.30 |
| 2026-05-17 00:00 |
21:56:33.48 |
-63:56:38.8 |
HIP 108493 |
18.10 |
| 2026-05-17 12:00 |
21:56:33.54 |
-63:56:57.1 |
HIP 108493 |
17.91 |
| 2026-05-18 00:00 |
21:56:33.57 |
-63:57:15.5 |
HIP 108493 |
17.72 |
| 2026-05-18 12:00 |
21:56:33.58 |
-63:57:33.8 |
HIP 108493 |
17.54 |
| 2026-05-19 00:00 |
21:56:33.55 |
-63:57:52.3 |
HIP 108493 |
17.36 |
| 2026-05-19 12:00 |
21:56:33.50 |
-63:58:10.8 |
HIP 108493 |
17.19 |
| 2026-05-20 00:00 |
21:56:33.42 |
-63:58:29.3 |
HIP 108493 |
17.03 |
| 2026-05-20 12:00 |
21:56:33.31 |
-63:58:47.8 |
HIP 108493 |
16.87 |
| 2026-05-21 00:00 |
21:56:33.17 |
-63:59:06.4 |
HIP 108493 |
16.72 |
| 2026-05-21 12:00 |
21:56:33.01 |
-63:59:25.1 |
HIP 108493 |
16.57 |
| 2026-05-22 00:00 |
21:56:32.82 |
-63:59:43.7 |
HIP 108493 |
16.44 |
| 2026-05-22 12:00 |
21:56:32.59 |
-64:00:02.4 |
HIP 108493 |
16.30 |
| 2026-05-23 00:00 |
21:56:32.35 |
-64:00:21.2 |
HIP 108493 |
16.18 |
| 2026-05-23 12:00 |
21:56:32.07 |
-64:00:39.9 |
HIP 108493 |
16.06 |
| 2026-05-24 00:00 |
21:56:31.76 |
-64:00:58.7 |
HIP 108493 |
15.96 |
| 2026-05-24 12:00 |
21:56:31.43 |
-64:01:17.5 |
HIP 108493 |
15.86 |
| 2026-05-25 00:00 |
21:56:31.07 |
-64:01:36.3 |
HIP 108493 |
15.76 |
| 2026-05-25 12:00 |
21:56:30.68 |
-64:01:55.2 |
HIP 108493 |
15.68 |
| 2026-05-26 00:00 |
21:56:30.27 |
-64:02:14.1 |
HIP 108493 |
15.61 |
| 2026-05-26 12:00 |
21:56:29.82 |
-64:02:33.0 |
HIP 108493 |
15.54 |
| 2026-05-27 00:00 |
21:56:29.35 |
-64:02:51.9 |
HIP 108493 |
15.48 |
| 2026-05-27 12:00 |
21:56:28.85 |
-64:03:10.9 |
HIP 108493 |
15.44 |
| 2026-05-28 00:00 |
21:56:28.33 |
-64:03:29.9 |
HIP 108493 |
15.40 |
| 2026-05-28 12:00 |
21:56:27.77 |
-64:03:48.8 |
HIP 108493 |
15.37 |
| 2026-05-29 00:00 |
21:56:27.19 |
-64:04:07.8 |
HIP 108493 |
15.35 |
| 2026-05-29 12:00 |
21:56:26.58 |
-64:04:26.9 |
HIP 108493 |
15.34 |
| 2026-05-30 00:00 |
21:56:25.94 |
-64:04:45.9 |
HIP 108493 |
15.34 |
| 2026-05-30 12:00 |
21:56:25.28 |
-64:05:04.9 |
HIP 108493 |
15.35 |
| 2026-05-31 00:00 |
21:56:24.59 |
-64:05:24.0 |
HIP 108493 |
15.37 |
| 2026-05-31 12:00 |
21:56:23.87 |
-64:05:43.0 |
HIP 108493 |
15.40 |
| 2026-06-01 00:00 |
21:56:23.12 |
-64:06:02.1 |
HIP 108493 |
15.44 |
| 2026-06-01 12:00 |
21:56:22.34 |
-64:06:21.2 |
HIP 108493 |
15.49 |
| 2026-06-02 00:00 |
21:56:21.54 |
-64:06:40.3 |
HIP 108493 |
15.55 |