メタデータ
| 項目 |
値 |
| Designation |
338P/McNaught |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2016-11-21T23:54:59.846400Z |
| Orbit solution date (soln_date, UTC) |
2025-02-13T09:13:12Z |
| Obs used |
882 |
| NEO |
- |
| M1 |
15.500 |
| K1 |
4.500 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2018-02-14.0000000 |
| e |
0.41033494 |
| q (au) |
2.301407 |
| a (au) |
3.902905 |
| i (deg) |
25.350404 |
| Ω (om, deg) |
9.805290 |
| ω (w, deg) |
4.508283 |
| M (ma, deg) |
57.394693 |
等級
散乱 + 全体線形
$$
M_a = (11.883 + 5.284\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
11.883 |
| n |
5.284 |
| gf |
0.999 |
| gb |
-0.937 |
| k |
1.000 |
| δ90 |
9.998 |
| 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) |
| 2026-07-29 00:00 |
10:17:41.64 |
+25:00:12.6 |
HIP 50321 |
23.29 |
| 2026-07-29 12:00 |
10:18:08.83 |
+24:56:35.5 |
HIP 50516 |
18.19 |
| 2026-07-30 00:00 |
10:18:36.03 |
+24:52:58.7 |
HIP 50516 |
11.68 |
| 2026-07-30 12:00 |
10:19:03.25 |
+24:49:22.1 |
HIP 50516 |
6.66 |
| 2026-07-31 00:00 |
10:19:30.48 |
+24:45:45.6 |
HIP 50516 |
7.40 |
| 2026-07-31 12:00 |
10:19:57.72 |
+24:42:09.4 |
HIP 50516 |
12.95 |
| 2026-08-01 00:00 |
10:20:24.97 |
+24:38:33.4 |
HIP 50516 |
19.58 |
| 2026-08-01 12:00 |
10:20:52.23 |
+24:34:57.6 |
HIP 50823 |
24.18 |
| 2026-08-02 00:00 |
10:21:19.51 |
+24:31:21.9 |
HIP 50823 |
18.50 |
| 2026-08-02 12:00 |
10:21:46.79 |
+24:27:46.5 |
HIP 50823 |
14.23 |
| 2026-08-03 00:00 |
10:22:14.09 |
+24:24:11.3 |
HIP 50823 |
12.85 |
| 2026-08-03 12:00 |
10:22:41.40 |
+24:20:36.3 |
HIP 50823 |
15.19 |
| 2026-08-04 00:00 |
10:23:08.71 |
+24:17:01.6 |
HIP 50823 |
19.97 |
| 2026-08-04 12:00 |
10:23:36.03 |
+24:13:27.0 |
HIP 50823 |
25.89 |
| 2026-08-05 00:00 |
10:24:03.37 |
+24:09:52.6 |
HIP 50998 |
30.00 |
| 2026-08-05 12:00 |
10:24:30.71 |
+24:06:18.5 |
HIP 50998 |
31.27 |
| 2026-08-06 00:00 |
10:24:58.05 |
+24:02:44.6 |
HIP 50998 |
34.03 |
| 2026-08-06 12:00 |
10:25:25.41 |
+23:59:10.9 |
HIP 50998 |
37.97 |
| 2026-08-07 00:00 |
10:25:52.77 |
+23:55:37.4 |
HIP 50998 |
42.75 |
| 2026-08-07 12:00 |
10:26:20.14 |
+23:52:04.2 |
HIP 51377 |
45.18 |
| 2026-08-08 00:00 |
10:26:47.51 |
+23:48:31.2 |
HIP 51377 |
39.72 |
| 2026-08-08 12:00 |
10:27:14.88 |
+23:44:58.4 |
HIP 51377 |
34.88 |
| 2026-08-09 00:00 |
10:27:42.26 |
+23:41:25.8 |
HIP 51377 |
30.97 |
| 2026-08-09 12:00 |
10:28:09.65 |
+23:37:53.5 |
HIP 51377 |
28.36 |
| 2026-08-10 00:00 |
10:28:37.04 |
+23:34:21.4 |
HIP 51377 |
27.43 |
| 2026-08-10 12:00 |
10:29:04.43 |
+23:30:49.6 |
HIP 51353 |
27.39 |
| 2026-08-11 00:00 |
10:29:31.82 |
+23:27:18.0 |
HIP 51353 |
23.69 |
| 2026-08-11 12:00 |
10:29:59.21 |
+23:23:46.7 |
HIP 51353 |
21.83 |
| 2026-08-12 00:00 |
10:30:26.60 |
+23:20:15.6 |
HIP 51353 |
22.28 |
| 2026-08-12 12:00 |
10:30:54.00 |
+23:16:44.8 |
HIP 51594 |
20.28 |
| 2026-08-13 00:00 |
10:31:21.39 |
+23:13:14.2 |
HIP 51594 |
15.06 |
| 2026-08-13 12:00 |
10:31:48.78 |
+23:09:44.0 |
HIP 51594 |
12.08 |
| 2026-08-14 00:00 |
10:32:16.17 |
+23:06:13.9 |
HIP 51594 |
12.98 |
| 2026-08-14 12:00 |
10:32:43.55 |
+23:02:44.2 |
HIP 51594 |
17.16 |
| 2026-08-15 00:00 |
10:33:10.93 |
+22:59:14.7 |
HIP 51594 |
22.89 |
| 2026-08-15 12:00 |
10:33:38.31 |
+22:55:45.5 |
HIP 51699 |
25.37 |
| 2026-08-16 00:00 |
10:34:05.69 |
+22:52:16.6 |
HIP 51699 |
29.07 |
| 2026-08-16 12:00 |
10:34:33.05 |
+22:48:47.9 |
HIP 51699 |
33.91 |
| 2026-08-17 00:00 |
10:35:00.42 |
+22:45:19.6 |
HIP 51699 |
39.48 |
| 2026-08-17 12:00 |
10:35:27.77 |
+22:41:51.5 |
HIP 51699 |
45.49 |
| 2026-08-18 00:00 |
10:35:55.12 |
+22:38:23.7 |
HIP 52042 |
44.60 |
| 2026-08-18 12:00 |
10:36:22.46 |
+22:34:56.2 |
HIP 52042 |
37.96 |
| 2026-08-19 00:00 |
10:36:49.79 |
+22:31:29.1 |
HIP 52042 |
31.57 |