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) |
| 2026-03-26 00:00 |
06:33:26.43 |
-56:36:02.0 |
HIP 31418 |
18.66 |
| 2026-03-26 12:00 |
06:33:26.13 |
-56:35:19.5 |
HIP 31418 |
19.19 |
| 2026-03-27 00:00 |
06:33:25.87 |
-56:34:37.0 |
HIP 31418 |
19.73 |
| 2026-03-27 12:00 |
06:33:25.66 |
-56:33:54.5 |
HIP 31418 |
20.27 |
| 2026-03-28 00:00 |
06:33:25.50 |
-56:33:12.0 |
HIP 31418 |
20.82 |
| 2026-03-28 12:00 |
06:33:25.38 |
-56:32:29.5 |
HIP 31418 |
21.38 |
| 2026-03-29 00:00 |
06:33:25.31 |
-56:31:47.0 |
HIP 31418 |
21.94 |
| 2026-03-29 12:00 |
06:33:25.28 |
-56:31:04.5 |
HIP 31418 |
22.50 |
| 2026-03-30 00:00 |
06:33:25.30 |
-56:30:22.1 |
HIP 31418 |
23.07 |
| 2026-03-30 12:00 |
06:33:25.36 |
-56:29:39.7 |
HIP 31418 |
23.64 |
| 2026-03-31 00:00 |
06:33:25.47 |
-56:28:57.3 |
HIP 31418 |
24.22 |
| 2026-03-31 12:00 |
06:33:25.63 |
-56:28:14.9 |
HIP 31418 |
24.80 |
| 2026-04-01 00:00 |
06:33:25.83 |
-56:27:32.6 |
HIP 31504 |
24.52 |
| 2026-04-01 12:00 |
06:33:26.07 |
-56:26:50.3 |
HIP 31504 |
24.10 |
| 2026-04-02 00:00 |
06:33:26.36 |
-56:26:08.0 |
HIP 31504 |
23.70 |
| 2026-04-02 12:00 |
06:33:26.70 |
-56:25:25.8 |
HIP 31504 |
23.30 |
| 2026-04-03 00:00 |
06:33:27.08 |
-56:24:43.6 |
HIP 31504 |
22.91 |
| 2026-04-03 12:00 |
06:33:27.51 |
-56:24:01.5 |
HIP 31504 |
22.53 |
| 2026-04-04 00:00 |
06:33:27.98 |
-56:23:19.4 |
HIP 31504 |
22.16 |
| 2026-04-04 12:00 |
06:33:28.49 |
-56:22:37.3 |
HIP 31504 |
21.80 |
| 2026-04-05 00:00 |
06:33:29.05 |
-56:21:55.3 |
HIP 31504 |
21.45 |
| 2026-04-05 12:00 |
06:33:29.66 |
-56:21:13.4 |
HIP 31504 |
21.12 |
| 2026-04-06 00:00 |
06:33:30.31 |
-56:20:31.5 |
HIP 31504 |
20.80 |
| 2026-04-06 12:00 |
06:33:31.00 |
-56:19:49.7 |
HIP 31504 |
20.49 |
| 2026-04-07 00:00 |
06:33:31.74 |
-56:19:08.0 |
HIP 31504 |
20.19 |
| 2026-04-07 12:00 |
06:33:32.52 |
-56:18:26.3 |
HIP 31504 |
19.92 |
| 2026-04-08 00:00 |
06:33:33.34 |
-56:17:44.7 |
HIP 31504 |
19.65 |
| 2026-04-08 12:00 |
06:33:34.21 |
-56:17:03.2 |
HIP 31504 |
19.40 |
| 2026-04-09 00:00 |
06:33:35.13 |
-56:16:21.8 |
HIP 31504 |
19.17 |
| 2026-04-09 12:00 |
06:33:36.08 |
-56:15:40.4 |
HIP 31504 |
18.96 |
| 2026-04-10 00:00 |
06:33:37.09 |
-56:14:59.1 |
HIP 31504 |
18.76 |
| 2026-04-10 12:00 |
06:33:38.13 |
-56:14:17.9 |
HIP 31504 |
18.59 |
| 2026-04-11 00:00 |
06:33:39.22 |
-56:13:36.8 |
HIP 31504 |
18.43 |
| 2026-04-11 12:00 |
06:33:40.35 |
-56:12:55.8 |
HIP 31504 |
18.29 |
| 2026-04-12 00:00 |
06:33:41.52 |
-56:12:14.9 |
HIP 31504 |
18.17 |
| 2026-04-12 12:00 |
06:33:42.74 |
-56:11:34.0 |
HIP 31504 |
18.07 |
| 2026-04-13 00:00 |
06:33:44.00 |
-56:10:53.3 |
HIP 31504 |
17.99 |
| 2026-04-13 12:00 |
06:33:45.30 |
-56:10:12.7 |
HIP 31504 |
17.93 |
| 2026-04-14 00:00 |
06:33:46.65 |
-56:09:32.2 |
HIP 31504 |
17.90 |
| 2026-04-14 12:00 |
06:33:48.03 |
-56:08:51.8 |
HIP 31504 |
17.88 |
| 2026-04-15 00:00 |
06:33:49.46 |
-56:08:11.5 |
HIP 31504 |
17.89 |
| 2026-04-15 12:00 |
06:33:50.93 |
-56:07:31.4 |
HIP 31504 |
17.91 |
| 2026-04-16 00:00 |
06:33:52.45 |
-56:06:51.3 |
HIP 31504 |
17.96 |