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 |
0.983 |
| 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) |
| 2026-05-12 00:00 |
09:06:02.70 |
+22:32:38.0 |
HIP 44731 |
14.59 |
| 2026-05-12 12:00 |
09:06:09.42 |
+22:31:43.1 |
HIP 44731 |
12.80 |
| 2026-05-13 00:00 |
09:06:16.27 |
+22:30:47.7 |
HIP 44731 |
10.98 |
| 2026-05-13 12:00 |
09:06:23.24 |
+22:29:51.9 |
HIP 44731 |
9.14 |
| 2026-05-14 00:00 |
09:06:30.34 |
+22:28:55.7 |
HIP 44731 |
7.28 |
| 2026-05-14 12:00 |
09:06:37.56 |
+22:27:59.0 |
HIP 44731 |
5.42 |
| 2026-05-15 00:00 |
09:06:44.90 |
+22:27:01.8 |
HIP 44731 |
3.59 |
| 2026-05-15 12:00 |
09:06:52.37 |
+22:26:04.3 |
HIP 44731 |
1.99 |
| 2026-05-16 00:00 |
09:06:59.96 |
+22:25:06.3 |
HIP 44731 |
1.69 |
| 2026-05-16 12:00 |
09:07:07.67 |
+22:24:07.8 |
HIP 44731 |
3.16 |
| 2026-05-17 00:00 |
09:07:15.50 |
+22:23:08.9 |
HIP 44731 |
5.06 |
| 2026-05-17 12:00 |
09:07:23.45 |
+22:22:09.6 |
HIP 44731 |
7.08 |
| 2026-05-18 00:00 |
09:07:31.52 |
+22:21:09.9 |
HIP 44808 |
8.06 |
| 2026-05-18 12:00 |
09:07:39.71 |
+22:20:09.7 |
HIP 44808 |
7.91 |
| 2026-05-19 00:00 |
09:07:48.01 |
+22:19:09.2 |
HIP 44808 |
8.34 |
| 2026-05-19 12:00 |
09:07:56.44 |
+22:18:08.2 |
HIP 44808 |
9.27 |
| 2026-05-20 00:00 |
09:08:04.98 |
+22:17:06.8 |
HIP 44808 |
10.60 |
| 2026-05-20 12:00 |
09:08:13.63 |
+22:16:05.0 |
HIP 44808 |
12.21 |
| 2026-05-21 00:00 |
09:08:22.40 |
+22:15:02.8 |
HIP 44808 |
14.01 |
| 2026-05-21 12:00 |
09:08:31.28 |
+22:14:00.2 |
HIP 44808 |
15.96 |
| 2026-05-22 00:00 |
09:08:40.27 |
+22:12:57.2 |
HIP 44946 |
14.00 |
| 2026-05-22 12:00 |
09:08:49.38 |
+22:11:53.8 |
HIP 44946 |
11.81 |
| 2026-05-23 00:00 |
09:08:58.59 |
+22:10:50.0 |
HIP 44946 |
9.69 |
| 2026-05-23 12:00 |
09:09:07.92 |
+22:09:45.8 |
HIP 44946 |
7.71 |
| 2026-05-24 00:00 |
09:09:17.35 |
+22:08:41.2 |
HIP 44946 |
6.04 |
| 2026-05-24 12:00 |
09:09:26.90 |
+22:07:36.3 |
HIP 44946 |
5.03 |
| 2026-05-25 00:00 |
09:09:36.55 |
+22:06:31.0 |
HIP 44946 |
5.14 |
| 2026-05-25 12:00 |
09:09:46.31 |
+22:05:25.3 |
HIP 44946 |
6.34 |
| 2026-05-26 00:00 |
09:09:56.17 |
+22:04:19.2 |
HIP 45033 |
7.30 |
| 2026-05-26 12:00 |
09:10:06.14 |
+22:03:12.8 |
HIP 45033 |
4.84 |
| 2026-05-27 00:00 |
09:10:16.21 |
+22:02:05.9 |
HIP 45033 |
2.55 |
| 2026-05-27 12:00 |
09:10:26.39 |
+22:00:58.8 |
HIP 45033 |
1.75 |
| 2026-05-28 00:00 |
09:10:36.67 |
+21:59:51.2 |
HIP 45033 |
3.67 |
| 2026-05-28 12:00 |
09:10:47.05 |
+21:58:43.3 |
HIP 45033 |
6.16 |
| 2026-05-29 00:00 |
09:10:57.53 |
+21:57:35.1 |
HIP 45033 |
8.78 |
| 2026-05-29 12:00 |
09:11:08.12 |
+21:56:26.5 |
HIP 45033 |
11.46 |
| 2026-05-30 00:00 |
09:11:18.80 |
+21:55:17.5 |
HIP 45033 |
14.17 |
| 2026-05-30 12:00 |
09:11:29.58 |
+21:54:08.2 |
HIP 45033 |
16.91 |
| 2026-05-31 00:00 |
09:11:40.46 |
+21:52:58.6 |
HIP 45033 |
19.68 |
| 2026-05-31 12:00 |
09:11:51.44 |
+21:51:48.6 |
HIP 45046 |
22.15 |
| 2026-06-01 00:00 |
09:12:02.51 |
+21:50:38.3 |
HIP 45046 |
23.85 |
| 2026-06-01 12:00 |
09:12:13.69 |
+21:49:27.6 |
HIP 45046 |
25.77 |
| 2026-06-02 00:00 |
09:12:24.95 |
+21:48:16.6 |
HIP 45046 |
27.87 |