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) |
| 2026-07-29 00:00 |
06:51:17.07 |
-12:29:08.0 |
HIP 32932 |
14.73 |
| 2026-07-29 12:00 |
06:51:19.13 |
-12:29:18.2 |
HIP 32932 |
14.39 |
| 2026-07-30 00:00 |
06:51:21.18 |
-12:29:28.6 |
HIP 32932 |
14.06 |
| 2026-07-30 12:00 |
06:51:23.22 |
-12:29:39.1 |
HIP 32932 |
13.74 |
| 2026-07-31 00:00 |
06:51:25.26 |
-12:29:49.8 |
HIP 32932 |
13.43 |
| 2026-07-31 12:00 |
06:51:27.29 |
-12:30:00.5 |
HIP 32932 |
13.14 |
| 2026-08-01 00:00 |
06:51:29.31 |
-12:30:11.5 |
HIP 32932 |
12.86 |
| 2026-08-01 12:00 |
06:51:31.32 |
-12:30:22.5 |
HIP 32932 |
12.59 |
| 2026-08-02 00:00 |
06:51:33.33 |
-12:30:33.7 |
HIP 32932 |
12.33 |
| 2026-08-02 12:00 |
06:51:35.32 |
-12:30:45.1 |
HIP 32932 |
12.10 |
| 2026-08-03 00:00 |
06:51:37.31 |
-12:30:56.6 |
HIP 32932 |
11.87 |
| 2026-08-03 12:00 |
06:51:39.29 |
-12:31:08.2 |
HIP 32932 |
11.67 |
| 2026-08-04 00:00 |
06:51:41.25 |
-12:31:19.9 |
HIP 32932 |
11.48 |
| 2026-08-04 12:00 |
06:51:43.21 |
-12:31:31.8 |
HIP 32932 |
11.31 |
| 2026-08-05 00:00 |
06:51:45.16 |
-12:31:43.8 |
HIP 32932 |
11.16 |
| 2026-08-05 12:00 |
06:51:47.10 |
-12:31:55.9 |
HIP 32932 |
11.03 |
| 2026-08-06 00:00 |
06:51:49.03 |
-12:32:08.2 |
HIP 32932 |
10.92 |
| 2026-08-06 12:00 |
06:51:50.95 |
-12:32:20.6 |
HIP 32932 |
10.83 |
| 2026-08-07 00:00 |
06:51:52.86 |
-12:32:33.1 |
HIP 32932 |
10.76 |
| 2026-08-07 12:00 |
06:51:54.77 |
-12:32:45.8 |
HIP 32932 |
10.71 |
| 2026-08-08 00:00 |
06:51:56.66 |
-12:32:58.5 |
HIP 32932 |
10.68 |
| 2026-08-08 12:00 |
06:51:58.54 |
-12:33:11.5 |
HIP 32932 |
10.68 |
| 2026-08-09 00:00 |
06:52:00.41 |
-12:33:24.5 |
HIP 32932 |
10.69 |
| 2026-08-09 12:00 |
06:52:02.27 |
-12:33:37.7 |
HIP 32932 |
10.73 |
| 2026-08-10 00:00 |
06:52:04.11 |
-12:33:50.9 |
HIP 32932 |
10.78 |
| 2026-08-10 12:00 |
06:52:05.95 |
-12:34:04.4 |
HIP 32932 |
10.86 |
| 2026-08-11 00:00 |
06:52:07.78 |
-12:34:17.9 |
HIP 32932 |
10.95 |
| 2026-08-11 12:00 |
06:52:09.59 |
-12:34:31.6 |
HIP 32932 |
11.06 |
| 2026-08-12 00:00 |
06:52:11.40 |
-12:34:45.3 |
HIP 32932 |
11.19 |
| 2026-08-12 12:00 |
06:52:13.19 |
-12:34:59.2 |
HIP 32932 |
11.34 |
| 2026-08-13 00:00 |
06:52:14.97 |
-12:35:13.3 |
HIP 32932 |
11.50 |
| 2026-08-13 12:00 |
06:52:16.74 |
-12:35:27.4 |
HIP 32932 |
11.68 |
| 2026-08-14 00:00 |
06:52:18.50 |
-12:35:41.7 |
HIP 32932 |
11.88 |
| 2026-08-14 12:00 |
06:52:20.24 |
-12:35:56.0 |
HIP 32932 |
12.08 |
| 2026-08-15 00:00 |
06:52:21.98 |
-12:36:10.5 |
HIP 32932 |
12.30 |
| 2026-08-15 12:00 |
06:52:23.70 |
-12:36:25.1 |
HIP 32932 |
12.53 |
| 2026-08-16 00:00 |
06:52:25.41 |
-12:36:39.9 |
HIP 32932 |
12.77 |
| 2026-08-16 12:00 |
06:52:27.10 |
-12:36:54.7 |
HIP 32932 |
13.02 |
| 2026-08-17 00:00 |
06:52:28.78 |
-12:37:09.6 |
HIP 32932 |
13.28 |
| 2026-08-17 12:00 |
06:52:30.46 |
-12:37:24.7 |
HIP 32932 |
13.55 |
| 2026-08-18 00:00 |
06:52:32.11 |
-12:37:39.8 |
HIP 32932 |
13.82 |
| 2026-08-18 12:00 |
06:52:33.76 |
-12:37:55.1 |
HIP 32932 |
14.11 |
| 2026-08-19 00:00 |
06:52:35.39 |
-12:38:10.5 |
HIP 32932 |
14.40 |