メタデータ
| 項目 |
値 |
| Designation |
C/2008 J4 (McNaught) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2008-06-19T09:29:06.619200Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:19Z |
| Obs used |
22 |
| NEO |
- |
| M1 |
16.500 |
| K1 |
12.750 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2008-05-17.0000000 |
| e |
1.00771428 |
| q (au) |
0.449265 |
| a (au) |
-58.238132 |
| i (deg) |
87.477450 |
| Ω (om, deg) |
289.372326 |
| ω (w, deg) |
93.055804 |
| M (ma, deg) |
-0.074059 |
等級
散乱 + 全体線形
$$
M_a = (16.126 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
16.126 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.885 |
| 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) |
| 2026-09-20 00:00 |
06:53:23.16 |
-56:17:59.8 |
HIP 32980 |
15.84 |
| 2026-09-20 12:00 |
06:53:24.39 |
-56:18:41.9 |
HIP 32980 |
15.40 |
| 2026-09-21 00:00 |
06:53:25.58 |
-56:19:24.0 |
HIP 32980 |
14.98 |
| 2026-09-21 12:00 |
06:53:26.73 |
-56:20:06.3 |
HIP 32980 |
14.57 |
| 2026-09-22 00:00 |
06:53:27.84 |
-56:20:48.6 |
HIP 32980 |
14.19 |
| 2026-09-22 12:00 |
06:53:28.90 |
-56:21:30.9 |
HIP 32980 |
13.83 |
| 2026-09-23 00:00 |
06:53:29.92 |
-56:22:13.4 |
HIP 32980 |
13.49 |
| 2026-09-23 12:00 |
06:53:30.90 |
-56:22:55.9 |
HIP 32980 |
13.17 |
| 2026-09-24 00:00 |
06:53:31.84 |
-56:23:38.5 |
HIP 32980 |
12.88 |
| 2026-09-24 12:00 |
06:53:32.74 |
-56:24:21.2 |
HIP 32980 |
12.63 |
| 2026-09-25 00:00 |
06:53:33.59 |
-56:25:03.9 |
HIP 32980 |
12.40 |
| 2026-09-25 12:00 |
06:53:34.40 |
-56:25:46.6 |
HIP 32980 |
12.20 |
| 2026-09-26 00:00 |
06:53:35.17 |
-56:26:29.5 |
HIP 32980 |
12.04 |
| 2026-09-26 12:00 |
06:53:35.89 |
-56:27:12.4 |
HIP 32980 |
11.92 |
| 2026-09-27 00:00 |
06:53:36.57 |
-56:27:55.3 |
HIP 32980 |
11.83 |
| 2026-09-27 12:00 |
06:53:37.21 |
-56:28:38.3 |
HIP 32980 |
11.78 |
| 2026-09-28 00:00 |
06:53:37.81 |
-56:29:21.3 |
HIP 32980 |
11.76 |
| 2026-09-28 12:00 |
06:53:38.36 |
-56:30:04.4 |
HIP 32980 |
11.79 |
| 2026-09-29 00:00 |
06:53:38.87 |
-56:30:47.5 |
HIP 32980 |
11.85 |
| 2026-09-29 12:00 |
06:53:39.33 |
-56:31:30.6 |
HIP 32980 |
11.95 |
| 2026-09-30 00:00 |
06:53:39.75 |
-56:32:13.8 |
HIP 32980 |
12.09 |
| 2026-09-30 12:00 |
06:53:40.13 |
-56:32:57.0 |
HIP 32980 |
12.26 |
| 2026-10-01 00:00 |
06:53:40.46 |
-56:33:40.2 |
HIP 32980 |
12.47 |
| 2026-10-01 12:00 |
06:53:40.75 |
-56:34:23.5 |
HIP 32980 |
12.71 |
| 2026-10-02 00:00 |
06:53:41.00 |
-56:35:06.7 |
HIP 32980 |
12.97 |
| 2026-10-02 12:00 |
06:53:41.20 |
-56:35:50.0 |
HIP 32980 |
13.27 |
| 2026-10-03 00:00 |
06:53:41.35 |
-56:36:33.4 |
HIP 32980 |
13.59 |
| 2026-10-03 12:00 |
06:53:41.47 |
-56:37:16.7 |
HIP 32980 |
13.94 |
| 2026-10-04 00:00 |
06:53:41.53 |
-56:38:00.0 |
HIP 32980 |
14.31 |
| 2026-10-04 12:00 |
06:53:41.56 |
-56:38:43.4 |
HIP 32980 |
14.70 |
| 2026-10-05 00:00 |
06:53:41.53 |
-56:39:26.7 |
HIP 32978 |
15.10 |
| 2026-10-05 12:00 |
06:53:41.47 |
-56:40:10.1 |
HIP 32978 |
15.51 |
| 2026-10-06 00:00 |
06:53:41.36 |
-56:40:53.4 |
HIP 32978 |
15.93 |
| 2026-10-06 12:00 |
06:53:41.20 |
-56:41:36.7 |
HIP 32978 |
16.37 |
| 2026-10-07 00:00 |
06:53:41.00 |
-56:42:20.1 |
HIP 32978 |
16.83 |
| 2026-10-07 12:00 |
06:53:40.75 |
-56:43:03.4 |
HIP 32978 |
17.30 |
| 2026-10-08 00:00 |
06:53:40.46 |
-56:43:46.7 |
HIP 32978 |
17.79 |
| 2026-10-08 12:00 |
06:53:40.12 |
-56:44:30.0 |
HIP 32978 |
18.28 |
| 2026-10-09 00:00 |
06:53:39.74 |
-56:45:13.2 |
HIP 32978 |
18.78 |
| 2026-10-09 12:00 |
06:53:39.31 |
-56:45:56.5 |
HIP 32978 |
19.30 |
| 2026-10-10 00:00 |
06:53:38.84 |
-56:46:39.7 |
HIP 32978 |
19.82 |
| 2026-10-10 12:00 |
06:53:38.32 |
-56:47:22.9 |
HIP 32978 |
20.35 |
| 2026-10-11 00:00 |
06:53:37.75 |
-56:48:06.0 |
HIP 33324 |
20.38 |