メタデータ
| 項目 |
値 |
| Designation |
442P/McNaught |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2022-08-20T19:07:02.740800Z |
| Orbit solution date (soln_date, UTC) |
2024-07-07T00:42:22Z |
| Obs used |
452 |
| NEO |
- |
| M1 |
10.500 |
| K1 |
19.250 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2018-08-20.0000000 |
| e |
0.53159899 |
| q (au) |
2.328281 |
| a (au) |
4.970701 |
| i (deg) |
6.053247 |
| Ω (om, deg) |
32.033725 |
| ω (w, deg) |
310.972640 |
| M (ma, deg) |
229.993643 |
等級
散乱 + 全体線形
$$
M_a = (15.717 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
15.717 |
| n |
2.000 |
| gf |
0.993 |
| gb |
-0.900 |
| k |
0.999 |
| δ90 |
1.000 |
| 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) |
| 2026-07-29 00:00 |
09:41:16.21 |
+19:06:30.8 |
HIP 47545 |
10.59 |
| 2026-07-29 12:00 |
09:41:33.80 |
+19:04:57.0 |
HIP 47545 |
7.99 |
| 2026-07-30 00:00 |
09:41:51.41 |
+19:03:23.2 |
HIP 47545 |
7.42 |
| 2026-07-30 12:00 |
09:42:09.04 |
+19:01:49.3 |
HIP 47545 |
9.27 |
| 2026-07-31 00:00 |
09:42:26.68 |
+19:00:15.4 |
HIP 47545 |
12.51 |
| 2026-07-31 12:00 |
09:42:44.34 |
+18:58:41.4 |
HIP 47545 |
16.34 |
| 2026-08-01 00:00 |
09:43:02.01 |
+18:57:07.4 |
HIP 47545 |
20.43 |
| 2026-08-01 12:00 |
09:43:19.70 |
+18:55:33.4 |
HIP 47779 |
17.04 |
| 2026-08-02 00:00 |
09:43:37.40 |
+18:53:59.3 |
HIP 47779 |
12.63 |
| 2026-08-02 12:00 |
09:43:55.12 |
+18:52:25.1 |
HIP 47779 |
8.27 |
| 2026-08-03 00:00 |
09:44:12.85 |
+18:50:51.0 |
HIP 47779 |
4.17 |
| 2026-08-03 12:00 |
09:44:30.59 |
+18:49:16.8 |
HIP 47779 |
2.54 |
| 2026-08-04 00:00 |
09:44:48.34 |
+18:47:42.6 |
HIP 47779 |
5.98 |
| 2026-08-04 12:00 |
09:45:06.11 |
+18:46:08.3 |
HIP 47779 |
10.26 |
| 2026-08-05 00:00 |
09:45:23.88 |
+18:44:34.1 |
HIP 47909 |
7.53 |
| 2026-08-05 12:00 |
09:45:41.67 |
+18:42:59.8 |
HIP 47909 |
3.13 |
| 2026-08-06 00:00 |
09:45:59.47 |
+18:41:25.5 |
HIP 47909 |
1.83 |
| 2026-08-06 12:00 |
09:46:17.27 |
+18:39:51.2 |
HIP 47909 |
6.11 |
| 2026-08-07 00:00 |
09:46:35.09 |
+18:38:16.8 |
HIP 47909 |
10.58 |
| 2026-08-07 12:00 |
09:46:52.91 |
+18:36:42.5 |
HIP 47909 |
15.07 |
| 2026-08-08 00:00 |
09:47:10.74 |
+18:35:08.2 |
HIP 47909 |
19.57 |
| 2026-08-08 12:00 |
09:47:28.57 |
+18:33:33.8 |
HIP 48103 |
20.27 |
| 2026-08-09 00:00 |
09:47:46.42 |
+18:31:59.5 |
HIP 48103 |
18.99 |
| 2026-08-09 12:00 |
09:48:04.27 |
+18:30:25.1 |
HIP 48103 |
18.75 |
| 2026-08-10 00:00 |
09:48:22.12 |
+18:28:50.8 |
HIP 48189 |
15.19 |
| 2026-08-10 12:00 |
09:48:39.98 |
+18:27:16.5 |
HIP 48189 |
11.54 |
| 2026-08-11 00:00 |
09:48:57.84 |
+18:25:42.2 |
HIP 48189 |
8.73 |
| 2026-08-11 12:00 |
09:49:15.71 |
+18:24:07.9 |
HIP 48189 |
7.76 |
| 2026-08-12 00:00 |
09:49:33.58 |
+18:22:33.6 |
HIP 48189 |
9.22 |
| 2026-08-12 12:00 |
09:49:51.45 |
+18:20:59.4 |
HIP 48189 |
12.27 |
| 2026-08-13 00:00 |
09:50:09.32 |
+18:19:25.1 |
HIP 48189 |
16.03 |
| 2026-08-13 12:00 |
09:50:27.19 |
+18:17:51.0 |
HIP 48366 |
17.93 |
| 2026-08-14 00:00 |
09:50:45.06 |
+18:16:16.8 |
HIP 48366 |
14.92 |
| 2026-08-14 12:00 |
09:51:02.93 |
+18:14:42.7 |
HIP 48366 |
12.84 |
| 2026-08-15 00:00 |
09:51:20.80 |
+18:13:08.6 |
HIP 48366 |
12.16 |
| 2026-08-15 12:00 |
09:51:38.67 |
+18:11:34.6 |
HIP 48366 |
13.11 |
| 2026-08-16 00:00 |
09:51:56.54 |
+18:10:00.7 |
HIP 48366 |
15.38 |
| 2026-08-16 12:00 |
09:52:14.40 |
+18:08:26.7 |
HIP 48366 |
18.50 |
| 2026-08-17 00:00 |
09:52:32.26 |
+18:06:52.9 |
HIP 48366 |
22.10 |
| 2026-08-17 12:00 |
09:52:50.11 |
+18:05:19.1 |
HIP 48562 |
21.84 |
| 2026-08-18 00:00 |
09:53:07.96 |
+18:03:45.4 |
HIP 48562 |
18.51 |
| 2026-08-18 12:00 |
09:53:25.80 |
+18:02:11.7 |
HIP 48562 |
15.79 |
| 2026-08-19 00:00 |
09:53:43.63 |
+18:00:38.1 |
HIP 48562 |
14.03 |