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
$$
M_a = (11.884 + 5.283\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
11.884 |
| n |
5.283 |
| gf |
0.999 |
| gb |
-0.937 |
| k |
1.000 |
| δ90 |
9.997 |
| 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) |
| 2026-03-26 00:00 |
09:13:37.32 |
+40:24:35.0 |
HIP 45218 |
8.11 |
| 2026-03-26 12:00 |
09:13:26.91 |
+40:21:35.0 |
HIP 45218 |
6.19 |
| 2026-03-27 00:00 |
09:13:16.83 |
+40:18:33.7 |
HIP 45218 |
6.11 |
| 2026-03-27 12:00 |
09:13:07.07 |
+40:15:31.1 |
HIP 45218 |
7.91 |
| 2026-03-28 00:00 |
09:12:57.64 |
+40:12:27.3 |
HIP 45218 |
10.67 |
| 2026-03-28 12:00 |
09:12:48.53 |
+40:09:22.3 |
HIP 45211 |
9.39 |
| 2026-03-29 00:00 |
09:12:39.75 |
+40:06:16.0 |
HIP 45211 |
6.48 |
| 2026-03-29 12:00 |
09:12:31.29 |
+40:03:08.6 |
HIP 45211 |
4.48 |
| 2026-03-30 00:00 |
09:12:23.15 |
+40:00:00.1 |
HIP 45211 |
4.73 |
| 2026-03-30 12:00 |
09:12:15.34 |
+39:56:50.4 |
HIP 45211 |
6.98 |
| 2026-03-31 00:00 |
09:12:07.84 |
+39:53:39.6 |
HIP 45211 |
9.94 |
| 2026-03-31 12:00 |
09:12:00.67 |
+39:50:27.7 |
HIP 45115 |
8.22 |
| 2026-04-01 00:00 |
09:11:53.81 |
+39:47:14.8 |
HIP 45115 |
5.19 |
| 2026-04-01 12:00 |
09:11:47.27 |
+39:44:00.8 |
HIP 45115 |
3.30 |
| 2026-04-02 00:00 |
09:11:41.04 |
+39:40:45.9 |
HIP 45115 |
4.39 |
| 2026-04-02 12:00 |
09:11:35.13 |
+39:37:29.9 |
HIP 45115 |
7.21 |
| 2026-04-03 00:00 |
09:11:29.54 |
+39:34:12.9 |
HIP 45115 |
10.44 |
| 2026-04-03 12:00 |
09:11:24.26 |
+39:30:55.0 |
HIP 45115 |
13.78 |
| 2026-04-04 00:00 |
09:11:19.29 |
+39:27:36.2 |
HIP 45126 |
16.20 |
| 2026-04-04 12:00 |
09:11:14.63 |
+39:24:16.4 |
HIP 45126 |
13.33 |
| 2026-04-05 00:00 |
09:11:10.28 |
+39:20:55.8 |
HIP 45126 |
10.76 |
| 2026-04-05 12:00 |
09:11:06.24 |
+39:17:34.3 |
HIP 45126 |
8.75 |
| 2026-04-06 00:00 |
09:11:02.51 |
+39:14:11.9 |
HIP 45126 |
7.76 |
| 2026-04-06 12:00 |
09:10:59.08 |
+39:10:48.6 |
HIP 45126 |
8.17 |
| 2026-04-07 00:00 |
09:10:55.96 |
+39:07:24.6 |
HIP 45126 |
9.81 |
| 2026-04-07 12:00 |
09:10:53.14 |
+39:03:59.7 |
HIP 45126 |
12.20 |
| 2026-04-08 00:00 |
09:10:50.63 |
+39:00:34.1 |
HIP 45126 |
14.98 |
| 2026-04-08 12:00 |
09:10:48.42 |
+38:57:07.7 |
HIP 45126 |
17.97 |
| 2026-04-09 00:00 |
09:10:46.50 |
+38:53:40.5 |
HIP 45126 |
21.10 |
| 2026-04-09 12:00 |
09:10:44.89 |
+38:50:12.6 |
HIP 45126 |
24.30 |
| 2026-04-10 00:00 |
09:10:43.57 |
+38:46:43.9 |
HIP 45067 |
26.00 |
| 2026-04-10 12:00 |
09:10:42.55 |
+38:43:14.6 |
HIP 45067 |
22.52 |
| 2026-04-11 00:00 |
09:10:41.82 |
+38:39:44.6 |
HIP 45067 |
19.02 |
| 2026-04-11 12:00 |
09:10:41.38 |
+38:36:13.9 |
HIP 45067 |
15.52 |
| 2026-04-12 00:00 |
09:10:41.24 |
+38:32:42.5 |
HIP 45067 |
12.01 |
| 2026-04-12 12:00 |
09:10:41.39 |
+38:29:10.5 |
HIP 45067 |
8.48 |
| 2026-04-13 00:00 |
09:10:41.83 |
+38:25:37.8 |
HIP 45067 |
4.96 |
| 2026-04-13 12:00 |
09:10:42.55 |
+38:22:04.6 |
HIP 45067 |
1.48 |
| 2026-04-14 00:00 |
09:10:43.56 |
+38:18:30.7 |
HIP 45067 |
2.26 |
| 2026-04-14 12:00 |
09:10:44.86 |
+38:14:56.3 |
HIP 45067 |
5.80 |
| 2026-04-15 00:00 |
09:10:46.43 |
+38:11:21.3 |
HIP 45067 |
9.38 |
| 2026-04-15 12:00 |
09:10:48.29 |
+38:07:45.7 |
HIP 45067 |
12.98 |
| 2026-04-16 00:00 |
09:10:50.43 |
+38:04:09.6 |
HIP 45067 |
16.60 |