メタデータ
| 項目 |
値 |
| Designation |
C/2007 P1 (McNaught) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2007-04-03T06:43:48.607680Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:10Z |
| Obs used |
16 |
| NEO |
- |
| M1 |
13.600 |
| K1 |
10.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2007-08-10.0000000 |
| e |
1.00042564 |
| q (au) |
0.522246 |
| a (au) |
-1226.959668 |
| i (deg) |
119.181662 |
| Ω (om, deg) |
187.061353 |
| ω (w, deg) |
90.192851 |
| M (ma, deg) |
0.002952 |
等級
散乱 + 全体線形
$$
M_a = (17.762 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
17.762 |
| n |
2.000 |
| gf |
0.999 |
| gb |
-1.000 |
| k |
0.800 |
| δ90 |
10.000 |
| 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 |
23:21:15.92 |
-72:20:32.0 |
HIP 115180 |
7.51 |
| 2026-05-12 12:00 |
23:21:20.17 |
-72:21:06.2 |
HIP 115180 |
7.59 |
| 2026-05-13 00:00 |
23:21:24.35 |
-72:21:40.5 |
HIP 115180 |
7.72 |
| 2026-05-13 12:00 |
23:21:28.47 |
-72:22:15.1 |
HIP 115180 |
7.89 |
| 2026-05-14 00:00 |
23:21:32.53 |
-72:22:49.9 |
HIP 115180 |
8.11 |
| 2026-05-14 12:00 |
23:21:36.52 |
-72:23:25.0 |
HIP 115180 |
8.37 |
| 2026-05-15 00:00 |
23:21:40.45 |
-72:24:00.2 |
HIP 115180 |
8.67 |
| 2026-05-15 12:00 |
23:21:44.31 |
-72:24:35.6 |
HIP 115180 |
9.00 |
| 2026-05-16 00:00 |
23:21:48.11 |
-72:25:11.2 |
HIP 115180 |
9.36 |
| 2026-05-16 12:00 |
23:21:51.84 |
-72:25:47.1 |
HIP 115180 |
9.75 |
| 2026-05-17 00:00 |
23:21:55.51 |
-72:26:23.1 |
HIP 115180 |
10.16 |
| 2026-05-17 12:00 |
23:21:59.11 |
-72:26:59.3 |
HIP 115180 |
10.59 |
| 2026-05-18 00:00 |
23:22:02.64 |
-72:27:35.7 |
HIP 115180 |
11.04 |
| 2026-05-18 12:00 |
23:22:06.11 |
-72:28:12.3 |
HIP 115180 |
11.51 |
| 2026-05-19 00:00 |
23:22:09.51 |
-72:28:49.1 |
HIP 115180 |
11.99 |
| 2026-05-19 12:00 |
23:22:12.84 |
-72:29:26.0 |
HIP 115180 |
12.49 |
| 2026-05-20 00:00 |
23:22:16.11 |
-72:30:03.2 |
HIP 115180 |
13.00 |
| 2026-05-20 12:00 |
23:22:19.31 |
-72:30:40.5 |
HIP 115180 |
13.51 |
| 2026-05-21 00:00 |
23:22:22.43 |
-72:31:18.0 |
HIP 115180 |
14.04 |
| 2026-05-21 12:00 |
23:22:25.49 |
-72:31:55.6 |
HIP 115180 |
14.58 |
| 2026-05-22 00:00 |
23:22:28.48 |
-72:32:33.5 |
HIP 115180 |
15.12 |
| 2026-05-22 12:00 |
23:22:31.40 |
-72:33:11.5 |
HIP 115180 |
15.68 |
| 2026-05-23 00:00 |
23:22:34.25 |
-72:33:49.6 |
HIP 115180 |
16.23 |
| 2026-05-23 12:00 |
23:22:37.04 |
-72:34:27.9 |
HIP 115180 |
16.80 |
| 2026-05-24 00:00 |
23:22:39.75 |
-72:35:06.4 |
HIP 115180 |
17.37 |
| 2026-05-24 12:00 |
23:22:42.39 |
-72:35:45.1 |
HIP 115180 |
17.94 |
| 2026-05-25 00:00 |
23:22:44.96 |
-72:36:23.9 |
HIP 115180 |
18.52 |
| 2026-05-25 12:00 |
23:22:47.46 |
-72:37:02.8 |
HIP 115180 |
19.10 |
| 2026-05-26 00:00 |
23:22:49.89 |
-72:37:41.9 |
HIP 115180 |
19.69 |
| 2026-05-26 12:00 |
23:22:52.24 |
-72:38:21.1 |
HIP 115180 |
20.28 |
| 2026-05-27 00:00 |
23:22:54.53 |
-72:39:00.5 |
HIP 115180 |
20.87 |
| 2026-05-27 12:00 |
23:22:56.74 |
-72:39:40.0 |
HIP 115180 |
21.47 |
| 2026-05-28 00:00 |
23:22:58.89 |
-72:40:19.7 |
HIP 115180 |
22.06 |
| 2026-05-28 12:00 |
23:23:00.95 |
-72:40:59.5 |
HIP 115757 |
21.79 |
| 2026-05-29 00:00 |
23:23:02.95 |
-72:41:39.4 |
HIP 115757 |
21.30 |
| 2026-05-29 12:00 |
23:23:04.88 |
-72:42:19.5 |
HIP 115757 |
20.83 |
| 2026-05-30 00:00 |
23:23:06.73 |
-72:42:59.6 |
HIP 115757 |
20.37 |
| 2026-05-30 12:00 |
23:23:08.50 |
-72:43:40.0 |
HIP 115757 |
19.93 |
| 2026-05-31 00:00 |
23:23:10.21 |
-72:44:20.4 |
HIP 115757 |
19.51 |
| 2026-05-31 12:00 |
23:23:11.84 |
-72:45:00.9 |
HIP 115757 |
19.11 |
| 2026-06-01 00:00 |
23:23:13.39 |
-72:45:41.6 |
HIP 115757 |
18.73 |
| 2026-06-01 12:00 |
23:23:14.88 |
-72:46:22.4 |
HIP 115757 |
18.37 |
| 2026-06-02 00:00 |
23:23:16.28 |
-72:47:03.3 |
HIP 115757 |
18.03 |