メタデータ
| 項目 |
値 |
| Designation |
446P/McNaught |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2012-08-14T16:28:43.587840Z |
| Orbit solution date (soln_date, UTC) |
2024-07-13T19:12:22Z |
| Obs used |
396 |
| NEO |
- |
| M1 |
17.500 |
| K1 |
6.750 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2015-01-08.0000000 |
| e |
0.64668523 |
| q (au) |
1.618504 |
| a (au) |
4.580911 |
| i (deg) |
16.571891 |
| Ω (om, deg) |
336.425077 |
| ω (w, deg) |
344.682612 |
| M (ma, deg) |
88.091854 |
等級
散乱 + 全体線形
$$
M_a = (17.429 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
17.429 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.849 |
| k |
0.999 |
| 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) |
| 2026-05-12 00:00 |
08:34:39.67 |
+25:40:33.0 |
HIP 42052 |
11.01 |
| 2026-05-12 12:00 |
08:34:47.24 |
+25:39:26.0 |
HIP 42052 |
10.94 |
| 2026-05-13 00:00 |
08:34:54.93 |
+25:38:18.8 |
HIP 42052 |
11.25 |
| 2026-05-13 12:00 |
08:35:02.74 |
+25:37:11.3 |
HIP 42052 |
11.94 |
| 2026-05-14 00:00 |
08:35:10.67 |
+25:36:03.5 |
HIP 42052 |
12.96 |
| 2026-05-14 12:00 |
08:35:18.71 |
+25:34:55.4 |
HIP 42052 |
14.25 |
| 2026-05-15 00:00 |
08:35:26.86 |
+25:33:47.1 |
HIP 42052 |
15.74 |
| 2026-05-15 12:00 |
08:35:35.13 |
+25:32:38.4 |
HIP 42052 |
17.41 |
| 2026-05-16 00:00 |
08:35:43.52 |
+25:31:29.5 |
HIP 42052 |
19.20 |
| 2026-05-16 12:00 |
08:35:52.01 |
+25:30:20.4 |
HIP 42052 |
21.10 |
| 2026-05-17 00:00 |
08:36:00.62 |
+25:29:10.9 |
HIP 42275 |
20.86 |
| 2026-05-17 12:00 |
08:36:09.34 |
+25:28:01.2 |
HIP 42275 |
18.61 |
| 2026-05-18 00:00 |
08:36:18.17 |
+25:26:51.2 |
HIP 42275 |
16.34 |
| 2026-05-18 12:00 |
08:36:27.11 |
+25:25:41.0 |
HIP 42275 |
14.06 |
| 2026-05-19 00:00 |
08:36:36.16 |
+25:24:30.5 |
HIP 42275 |
11.79 |
| 2026-05-19 12:00 |
08:36:45.32 |
+25:23:19.7 |
HIP 42275 |
9.54 |
| 2026-05-20 00:00 |
08:36:54.58 |
+25:22:08.7 |
HIP 42275 |
7.35 |
| 2026-05-20 12:00 |
08:37:03.95 |
+25:20:57.5 |
HIP 42275 |
5.34 |
| 2026-05-21 00:00 |
08:37:13.43 |
+25:19:46.0 |
HIP 42275 |
3.85 |
| 2026-05-21 12:00 |
08:37:23.01 |
+25:18:34.2 |
HIP 42275 |
3.63 |
| 2026-05-22 00:00 |
08:37:32.69 |
+25:17:22.2 |
HIP 42275 |
4.90 |
| 2026-05-22 12:00 |
08:37:42.48 |
+25:16:10.0 |
HIP 42275 |
6.90 |
| 2026-05-23 00:00 |
08:37:52.36 |
+25:14:57.5 |
HIP 42275 |
9.18 |
| 2026-05-23 12:00 |
08:38:02.35 |
+25:13:44.8 |
HIP 42275 |
11.60 |
| 2026-05-24 00:00 |
08:38:12.44 |
+25:12:31.9 |
HIP 42275 |
14.09 |
| 2026-05-24 12:00 |
08:38:22.63 |
+25:11:18.7 |
HIP 42275 |
16.63 |
| 2026-05-25 00:00 |
08:38:32.91 |
+25:10:05.3 |
HIP 42275 |
19.22 |
| 2026-05-25 12:00 |
08:38:43.30 |
+25:08:51.6 |
HIP 42275 |
21.83 |
| 2026-05-26 00:00 |
08:38:53.78 |
+25:07:37.8 |
HIP 42275 |
24.48 |
| 2026-05-26 12:00 |
08:39:04.35 |
+25:06:23.7 |
HIP 42275 |
27.15 |
| 2026-05-27 00:00 |
08:39:15.03 |
+25:05:09.4 |
HIP 42479 |
28.38 |
| 2026-05-27 12:00 |
08:39:25.79 |
+25:03:54.9 |
HIP 42479 |
26.81 |
| 2026-05-28 00:00 |
08:39:36.65 |
+25:02:40.1 |
HIP 42479 |
25.44 |
| 2026-05-28 12:00 |
08:39:47.60 |
+25:01:25.2 |
HIP 42479 |
24.31 |
| 2026-05-29 00:00 |
08:39:58.65 |
+25:00:10.0 |
HIP 42479 |
23.46 |
| 2026-05-29 12:00 |
08:40:09.78 |
+24:58:54.6 |
HIP 42479 |
22.92 |
| 2026-05-30 00:00 |
08:40:21.01 |
+24:57:39.0 |
HIP 42479 |
22.72 |
| 2026-05-30 12:00 |
08:40:32.32 |
+24:56:23.2 |
HIP 42479 |
22.89 |
| 2026-05-31 00:00 |
08:40:43.73 |
+24:55:07.2 |
HIP 42703 |
20.91 |
| 2026-05-31 12:00 |
08:40:55.22 |
+24:53:51.0 |
HIP 42703 |
19.03 |
| 2026-06-01 00:00 |
08:41:06.80 |
+24:52:34.6 |
HIP 42703 |
17.43 |
| 2026-06-01 12:00 |
08:41:18.47 |
+24:51:17.9 |
HIP 42703 |
16.19 |
| 2026-06-02 00:00 |
08:41:30.22 |
+24:50:01.1 |
HIP 42703 |
15.40 |