メタデータ
| 項目 |
値 |
| Designation |
C/1999 K1 (SOHO) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1999-05-21T08:52:48Z |
| Orbit solution date (soln_date, UTC) |
- |
| Obs used |
40 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1999-05-21.3700000 |
| e |
1.00000000 |
| q (au) |
0.005100 |
| a (au) |
- |
| i (deg) |
143.780000 |
| Ω (om, deg) |
5.490000 |
| ω (w, deg) |
83.510000 |
| M (ma, deg) |
- |
等級
散乱 + 全体線形
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| 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) |
| 2026-03-26 00:00 |
06:44:52.92 |
-13:02:41.8 |
HIP 32347 |
10.37 |
| 2026-03-26 12:00 |
06:44:52.68 |
-13:02:21.1 |
HIP 32347 |
10.72 |
| 2026-03-27 00:00 |
06:44:52.46 |
-13:02:00.5 |
HIP 32347 |
11.06 |
| 2026-03-27 12:00 |
06:44:52.26 |
-13:01:39.9 |
HIP 32347 |
11.40 |
| 2026-03-28 00:00 |
06:44:52.07 |
-13:01:19.2 |
HIP 32347 |
11.74 |
| 2026-03-28 12:00 |
06:44:51.91 |
-13:00:58.6 |
HIP 32347 |
12.08 |
| 2026-03-29 00:00 |
06:44:51.77 |
-13:00:38.0 |
HIP 32347 |
12.42 |
| 2026-03-29 12:00 |
06:44:51.65 |
-13:00:17.5 |
HIP 32347 |
12.75 |
| 2026-03-30 00:00 |
06:44:51.55 |
-12:59:56.9 |
HIP 32347 |
13.09 |
| 2026-03-30 12:00 |
06:44:51.47 |
-12:59:36.4 |
HIP 32347 |
13.42 |
| 2026-03-31 00:00 |
06:44:51.41 |
-12:59:15.9 |
HIP 32347 |
13.75 |
| 2026-03-31 12:00 |
06:44:51.37 |
-12:58:55.4 |
HIP 32347 |
14.08 |
| 2026-04-01 00:00 |
06:44:51.35 |
-12:58:35.0 |
HIP 32347 |
14.41 |
| 2026-04-01 12:00 |
06:44:51.35 |
-12:58:14.6 |
HIP 32347 |
14.74 |
| 2026-04-02 00:00 |
06:44:51.37 |
-12:57:54.2 |
HIP 32347 |
15.07 |
| 2026-04-02 12:00 |
06:44:51.42 |
-12:57:33.8 |
HIP 32347 |
15.39 |
| 2026-04-03 00:00 |
06:44:51.48 |
-12:57:13.5 |
HIP 32347 |
15.72 |
| 2026-04-03 12:00 |
06:44:51.56 |
-12:56:53.2 |
HIP 32347 |
16.04 |
| 2026-04-04 00:00 |
06:44:51.66 |
-12:56:32.9 |
HIP 32347 |
16.36 |
| 2026-04-04 12:00 |
06:44:51.79 |
-12:56:12.7 |
HIP 32347 |
16.68 |
| 2026-04-05 00:00 |
06:44:51.93 |
-12:55:52.5 |
HIP 32347 |
17.00 |
| 2026-04-05 12:00 |
06:44:52.09 |
-12:55:32.3 |
HIP 32347 |
17.32 |
| 2026-04-06 00:00 |
06:44:52.28 |
-12:55:12.2 |
HIP 32347 |
17.64 |
| 2026-04-06 12:00 |
06:44:52.48 |
-12:54:52.2 |
HIP 32347 |
17.96 |
| 2026-04-07 00:00 |
06:44:52.70 |
-12:54:32.1 |
HIP 32347 |
18.28 |
| 2026-04-07 12:00 |
06:44:52.95 |
-12:54:12.2 |
HIP 32347 |
18.59 |
| 2026-04-08 00:00 |
06:44:53.21 |
-12:53:52.2 |
HIP 32347 |
18.91 |
| 2026-04-08 12:00 |
06:44:53.49 |
-12:53:32.3 |
HIP 32347 |
19.22 |
| 2026-04-09 00:00 |
06:44:53.80 |
-12:53:12.5 |
HIP 32347 |
19.53 |
| 2026-04-09 12:00 |
06:44:54.12 |
-12:52:52.7 |
HIP 32442 |
19.84 |
| 2026-04-10 00:00 |
06:44:54.46 |
-12:52:33.0 |
HIP 32442 |
19.75 |
| 2026-04-10 12:00 |
06:44:54.83 |
-12:52:13.3 |
HIP 32442 |
19.67 |
| 2026-04-11 00:00 |
06:44:55.21 |
-12:51:53.6 |
HIP 32442 |
19.60 |
| 2026-04-11 12:00 |
06:44:55.61 |
-12:51:34.0 |
HIP 32442 |
19.52 |
| 2026-04-12 00:00 |
06:44:56.03 |
-12:51:14.5 |
HIP 32442 |
19.44 |
| 2026-04-12 12:00 |
06:44:56.47 |
-12:50:55.1 |
HIP 32442 |
19.36 |
| 2026-04-13 00:00 |
06:44:56.94 |
-12:50:35.7 |
HIP 32442 |
19.29 |
| 2026-04-13 12:00 |
06:44:57.42 |
-12:50:16.3 |
HIP 32442 |
19.21 |
| 2026-04-14 00:00 |
06:44:57.92 |
-12:49:57.0 |
HIP 32442 |
19.14 |
| 2026-04-14 12:00 |
06:44:58.44 |
-12:49:37.8 |
HIP 32442 |
19.06 |
| 2026-04-15 00:00 |
06:44:58.98 |
-12:49:18.7 |
HIP 32442 |
18.99 |
| 2026-04-15 12:00 |
06:44:59.54 |
-12:48:59.6 |
HIP 32442 |
18.92 |
| 2026-04-16 00:00 |
06:45:00.12 |
-12:48:40.6 |
HIP 32442 |
18.85 |