メタデータ
| 項目 |
値 |
| Designation |
320P/McNaught |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2015-08-08T16:38:08.764800Z |
| Orbit solution date (soln_date, UTC) |
2026-08-21T14:12:18Z |
| Obs used |
134 |
| NEO |
Yes |
| M1 |
19.800 |
| K1 |
12.750 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2013-01-09.0000000 |
| e |
0.68254557 |
| q (au) |
0.984612 |
| a (au) |
3.101586 |
| i (deg) |
4.895780 |
| Ω (om, deg) |
295.955140 |
| ω (w, deg) |
0.617314 |
| M (ma, deg) |
190.082623 |
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
ファインディングチャート
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
03:05:42.08 |
+28:36:42.3 |
HIP 14423 |
17.77 |
| 2026-09-20 12:00 |
03:05:09.68 |
+28:36:10.0 |
HIP 14270 |
16.37 |
| 2026-09-21 00:00 |
03:04:36.51 |
+28:35:32.2 |
HIP 14270 |
9.50 |
| 2026-09-21 12:00 |
03:04:02.56 |
+28:34:48.7 |
HIP 14270 |
4.31 |
| 2026-09-22 00:00 |
03:03:27.85 |
+28:33:59.7 |
HIP 14270 |
7.80 |
| 2026-09-22 12:00 |
03:02:52.40 |
+28:33:05.1 |
HIP 14270 |
15.00 |
| 2026-09-23 00:00 |
03:02:16.21 |
+28:32:04.9 |
HIP 14232 |
22.73 |
| 2026-09-23 12:00 |
03:01:39.29 |
+28:30:59.0 |
HIP 14028 |
17.34 |
| 2026-09-24 00:00 |
03:01:01.67 |
+28:29:47.4 |
HIP 14028 |
11.01 |
| 2026-09-24 12:00 |
03:00:23.35 |
+28:28:30.1 |
HIP 14028 |
8.99 |
| 2026-09-25 00:00 |
02:59:44.34 |
+28:27:07.2 |
HIP 14028 |
13.71 |
| 2026-09-25 12:00 |
02:59:04.67 |
+28:25:38.5 |
HIP 14028 |
21.24 |
| 2026-09-26 00:00 |
02:58:24.33 |
+28:24:04.0 |
HIP 14028 |
29.65 |
| 2026-09-26 12:00 |
02:57:43.36 |
+28:22:23.8 |
HIP 13659 |
25.23 |
| 2026-09-27 00:00 |
02:57:01.76 |
+28:20:37.9 |
HIP 13659 |
15.96 |
| 2026-09-27 12:00 |
02:56:19.54 |
+28:18:46.2 |
HIP 13659 |
6.69 |
| 2026-09-28 00:00 |
02:55:36.73 |
+28:16:48.7 |
HIP 13659 |
3.87 |
| 2026-09-28 12:00 |
02:54:53.34 |
+28:14:45.5 |
HIP 13615 |
9.29 |
| 2026-09-29 00:00 |
02:54:09.38 |
+28:12:36.4 |
HIP 13615 |
17.20 |
| 2026-09-29 12:00 |
02:53:24.87 |
+28:10:21.7 |
HIP 13423 |
9.30 |
| 2026-09-30 00:00 |
02:52:39.82 |
+28:08:01.1 |
HIP 13423 |
4.32 |
| 2026-09-30 12:00 |
02:51:54.26 |
+28:05:34.8 |
HIP 13423 |
12.72 |
| 2026-10-01 00:00 |
02:51:08.19 |
+28:03:02.8 |
HIP 13423 |
22.90 |
| 2026-10-01 12:00 |
02:50:21.65 |
+28:00:25.0 |
HIP 13423 |
33.39 |
| 2026-10-02 00:00 |
02:49:34.63 |
+27:57:41.6 |
HIP 13209 |
42.39 |
| 2026-10-02 12:00 |
02:48:47.17 |
+27:54:52.4 |
HIP 13209 |
42.33 |
| 2026-10-03 00:00 |
02:47:59.28 |
+27:51:57.6 |
HIP 13209 |
44.97 |
| 2026-10-03 12:00 |
02:47:10.99 |
+27:48:57.1 |
HIP 12799 |
37.52 |
| 2026-10-04 00:00 |
02:46:22.29 |
+27:45:51.0 |
HIP 12799 |
29.03 |
| 2026-10-04 12:00 |
02:45:33.23 |
+27:42:39.4 |
HIP 12799 |
22.99 |
| 2026-10-05 00:00 |
02:44:43.82 |
+27:39:22.2 |
HIP 12719 |
17.26 |
| 2026-10-05 12:00 |
02:43:54.07 |
+27:35:59.6 |
HIP 12719 |
8.78 |
| 2026-10-06 00:00 |
02:43:04.02 |
+27:32:31.5 |
HIP 12719 |
11.15 |
| 2026-10-06 12:00 |
02:42:13.67 |
+27:28:58.1 |
HIP 12719 |
21.12 |
| 2026-10-07 00:00 |
02:41:23.06 |
+27:25:19.3 |
HIP 12526 |
23.31 |
| 2026-10-07 12:00 |
02:40:32.19 |
+27:21:35.3 |
HIP 12489 |
18.04 |
| 2026-10-08 00:00 |
02:39:41.11 |
+27:17:46.2 |
HIP 12489 |
19.41 |
| 2026-10-08 12:00 |
02:38:49.81 |
+27:13:51.9 |
HIP 12214 |
22.02 |
| 2026-10-09 00:00 |
02:37:58.34 |
+27:09:52.5 |
HIP 12214 |
9.90 |
| 2026-10-09 12:00 |
02:37:06.71 |
+27:05:48.3 |
HIP 12214 |
2.30 |
| 2026-10-10 00:00 |
02:36:14.94 |
+27:01:39.1 |
HIP 12124 |
8.44 |
| 2026-10-10 12:00 |
02:35:23.06 |
+26:57:25.2 |
HIP 12124 |
16.33 |
| 2026-10-11 00:00 |
02:34:31.08 |
+26:53:06.6 |
HIP 12124 |
27.73 |