メタデータ
| 項目 |
値 |
| Designation |
C/1998 J1 (SOHO) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1998-05-08T14:51:07.577280Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:53Z |
| Obs used |
318 |
| NEO |
- |
| M1 |
6.500 |
| K1 |
7.500 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
1998-06-09.0000000 |
| e |
1.00017217 |
| q (au) |
0.153214 |
| a (au) |
-889.893232 |
| i (deg) |
62.931830 |
| Ω (om, deg) |
351.648559 |
| ω (w, deg) |
110.557189 |
| M (ma, deg) |
0.001165 |
等級
散乱 + 全体線形
$$
M_a = (6.621 + 2.438\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
6.621 |
| n |
2.438 |
| gf |
0.800 |
| gb |
-0.500 |
| k |
0.800 |
| δ90 |
1.000 |
| 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
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 1998-05-08 |
1998-05-20 |
+3.7861 |
+1.870 |
| 1998-05-20 |
1998-05-31 |
-2.0767 |
+0.554 |
| 1998-05-31 |
1998-07-02 |
+0.2386 |
-0.078 |
| 1998-07-02 |
1998-08-15 |
+14.9567 |
-2.015 |
log10 r = log10(太陽距離/AU)、Δ = 地球距離(AU)
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
22:33:23.41 |
-78:20:30.6 |
HIP 111049 |
13.27 |
| 2026-06-01 12:00 |
22:33:22.80 |
-78:21:02.1 |
HIP 111049 |
13.55 |
| 2026-06-02 00:00 |
22:33:22.11 |
-78:21:33.6 |
HIP 111049 |
13.85 |
| 2026-06-02 12:00 |
22:33:21.32 |
-78:22:05.2 |
HIP 111049 |
14.16 |
| 2026-06-03 00:00 |
22:33:20.45 |
-78:22:36.8 |
HIP 111049 |
14.47 |
| 2026-06-03 12:00 |
22:33:19.48 |
-78:23:08.4 |
HIP 111049 |
14.80 |
| 2026-06-04 00:00 |
22:33:18.43 |
-78:23:40.0 |
HIP 111486 |
14.41 |
| 2026-06-04 12:00 |
22:33:17.29 |
-78:24:11.6 |
HIP 111486 |
13.96 |
| 2026-06-05 00:00 |
22:33:16.06 |
-78:24:43.2 |
HIP 111486 |
13.51 |
| 2026-06-05 12:00 |
22:33:14.74 |
-78:25:14.8 |
HIP 111486 |
13.06 |
| 2026-06-06 00:00 |
22:33:13.33 |
-78:25:46.5 |
HIP 111486 |
12.63 |
| 2026-06-06 12:00 |
22:33:11.83 |
-78:26:18.1 |
HIP 111486 |
12.21 |
| 2026-06-07 00:00 |
22:33:10.24 |
-78:26:49.7 |
HIP 111486 |
11.80 |
| 2026-06-07 12:00 |
22:33:08.56 |
-78:27:21.3 |
HIP 111486 |
11.40 |
| 2026-06-08 00:00 |
22:33:06.79 |
-78:27:52.9 |
HIP 111486 |
11.01 |
| 2026-06-08 12:00 |
22:33:04.93 |
-78:28:24.5 |
HIP 111486 |
10.64 |
| 2026-06-09 00:00 |
22:33:02.98 |
-78:28:56.1 |
HIP 111486 |
10.29 |
| 2026-06-09 12:00 |
22:33:00.94 |
-78:29:27.7 |
HIP 111486 |
9.96 |
| 2026-06-10 00:00 |
22:32:58.81 |
-78:29:59.2 |
HIP 111486 |
9.65 |
| 2026-06-10 12:00 |
22:32:56.59 |
-78:30:30.8 |
HIP 111486 |
9.36 |
| 2026-06-11 00:00 |
22:32:54.27 |
-78:31:02.3 |
HIP 111486 |
9.10 |
| 2026-06-11 12:00 |
22:32:51.87 |
-78:31:33.8 |
HIP 111486 |
8.87 |
| 2026-06-12 00:00 |
22:32:49.37 |
-78:32:05.2 |
HIP 111486 |
8.67 |
| 2026-06-12 12:00 |
22:32:46.79 |
-78:32:36.7 |
HIP 111486 |
8.50 |
| 2026-06-13 00:00 |
22:32:44.11 |
-78:33:08.1 |
HIP 111486 |
8.37 |
| 2026-06-13 12:00 |
22:32:41.35 |
-78:33:39.4 |
HIP 111486 |
8.27 |
| 2026-06-14 00:00 |
22:32:38.49 |
-78:34:10.8 |
HIP 111486 |
8.22 |
| 2026-06-14 12:00 |
22:32:35.54 |
-78:34:42.1 |
HIP 111486 |
8.20 |
| 2026-06-15 00:00 |
22:32:32.50 |
-78:35:13.3 |
HIP 111486 |
8.23 |
| 2026-06-15 12:00 |
22:32:29.37 |
-78:35:44.5 |
HIP 111486 |
8.29 |
| 2026-06-16 00:00 |
22:32:26.15 |
-78:36:15.7 |
HIP 111486 |
8.39 |
| 2026-06-16 12:00 |
22:32:22.83 |
-78:36:46.8 |
HIP 111486 |
8.53 |
| 2026-06-17 00:00 |
22:32:19.43 |
-78:37:17.8 |
HIP 111486 |
8.71 |
| 2026-06-17 12:00 |
22:32:15.94 |
-78:37:48.8 |
HIP 111486 |
8.92 |
| 2026-06-18 00:00 |
22:32:12.35 |
-78:38:19.7 |
HIP 111486 |
9.16 |
| 2026-06-18 12:00 |
22:32:08.68 |
-78:38:50.6 |
HIP 111486 |
9.43 |
| 2026-06-19 00:00 |
22:32:04.91 |
-78:39:21.4 |
HIP 111486 |
9.73 |
| 2026-06-19 12:00 |
22:32:01.06 |
-78:39:52.2 |
HIP 111486 |
10.05 |
| 2026-06-20 00:00 |
22:31:57.11 |
-78:40:22.8 |
HIP 111486 |
10.40 |
| 2026-06-20 12:00 |
22:31:53.08 |
-78:40:53.4 |
HIP 111486 |
10.76 |
| 2026-06-21 00:00 |
22:31:48.96 |
-78:41:24.0 |
HIP 111486 |
11.15 |
| 2026-06-21 12:00 |
22:31:44.74 |
-78:41:54.4 |
HIP 111486 |
11.54 |
| 2026-06-22 00:00 |
22:31:40.44 |
-78:42:24.8 |
HIP 111504 |
11.69 |