メタデータ
| 項目 |
値 |
| Designation |
C/2009 F5 (McNaught) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2008-11-04T19:50:20.624640Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:30Z |
| Obs used |
444 |
| NEO |
- |
| M1 |
12.800 |
| 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) |
2009-05-07.0000000 |
| e |
0.97199145 |
| q (au) |
2.245337 |
| a (au) |
80.166145 |
| i (deg) |
84.990355 |
| Ω (om, deg) |
219.064143 |
| ω (w, deg) |
297.366826 |
| M (ma, deg) |
0.251524 |
等級
散乱 + 全体線形
$$
M_a = (14.104 + 2.537\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
14.104 |
| n |
2.537 |
| gf |
1.000 |
| gb |
-0.637 |
| 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 |
18:44:43.53 |
+64:04:22.4 |
HIP 92100 |
12.26 |
| 2026-05-12 12:00 |
18:44:38.85 |
+64:05:03.1 |
HIP 92100 |
12.29 |
| 2026-05-13 00:00 |
18:44:34.12 |
+64:05:43.6 |
HIP 92100 |
12.38 |
| 2026-05-13 12:00 |
18:44:29.33 |
+64:06:23.7 |
HIP 92100 |
12.54 |
| 2026-05-14 00:00 |
18:44:24.49 |
+64:07:03.6 |
HIP 92100 |
12.76 |
| 2026-05-14 12:00 |
18:44:19.59 |
+64:07:43.1 |
HIP 92100 |
13.04 |
| 2026-05-15 00:00 |
18:44:14.64 |
+64:08:22.3 |
HIP 92100 |
13.37 |
| 2026-05-15 12:00 |
18:44:09.64 |
+64:09:01.2 |
HIP 92100 |
13.75 |
| 2026-05-16 00:00 |
18:44:04.59 |
+64:09:39.8 |
HIP 92100 |
14.18 |
| 2026-05-16 12:00 |
18:43:59.48 |
+64:10:18.0 |
HIP 92100 |
14.65 |
| 2026-05-17 00:00 |
18:43:54.33 |
+64:10:56.0 |
HIP 92100 |
15.16 |
| 2026-05-17 12:00 |
18:43:49.12 |
+64:11:33.5 |
HIP 92100 |
15.70 |
| 2026-05-18 00:00 |
18:43:43.86 |
+64:12:10.8 |
HIP 92100 |
16.27 |
| 2026-05-18 12:00 |
18:43:38.55 |
+64:12:47.7 |
HIP 92100 |
16.87 |
| 2026-05-19 00:00 |
18:43:33.20 |
+64:13:24.3 |
HIP 92100 |
17.50 |
| 2026-05-19 12:00 |
18:43:27.79 |
+64:14:00.5 |
HIP 92100 |
18.15 |
| 2026-05-20 00:00 |
18:43:22.34 |
+64:14:36.4 |
HIP 92100 |
18.81 |
| 2026-05-20 12:00 |
18:43:16.84 |
+64:15:12.0 |
HIP 92100 |
19.50 |
| 2026-05-21 00:00 |
18:43:11.29 |
+64:15:47.1 |
HIP 92100 |
20.20 |
| 2026-05-21 12:00 |
18:43:05.69 |
+64:16:22.0 |
HIP 92100 |
20.91 |
| 2026-05-22 00:00 |
18:43:00.05 |
+64:16:56.5 |
HIP 92100 |
21.64 |
| 2026-05-22 12:00 |
18:42:54.36 |
+64:17:30.6 |
HIP 92100 |
22.37 |
| 2026-05-23 00:00 |
18:42:48.63 |
+64:18:04.4 |
HIP 92100 |
23.12 |
| 2026-05-23 12:00 |
18:42:42.85 |
+64:18:37.8 |
HIP 92100 |
23.87 |
| 2026-05-24 00:00 |
18:42:37.03 |
+64:19:10.8 |
HIP 92100 |
24.64 |
| 2026-05-24 12:00 |
18:42:31.16 |
+64:19:43.5 |
HIP 92100 |
25.41 |
| 2026-05-25 00:00 |
18:42:25.25 |
+64:20:15.8 |
HIP 92100 |
26.18 |
| 2026-05-25 12:00 |
18:42:19.29 |
+64:20:47.7 |
HIP 92100 |
26.97 |
| 2026-05-26 00:00 |
18:42:13.30 |
+64:21:19.2 |
HIP 92100 |
27.75 |
| 2026-05-26 12:00 |
18:42:07.26 |
+64:21:50.4 |
HIP 92100 |
28.54 |
| 2026-05-27 00:00 |
18:42:01.18 |
+64:22:21.2 |
HIP 92100 |
29.34 |
| 2026-05-27 12:00 |
18:41:55.06 |
+64:22:51.6 |
HIP 92100 |
30.14 |
| 2026-05-28 00:00 |
18:41:48.90 |
+64:23:21.7 |
HIP 91950 |
30.90 |
| 2026-05-28 12:00 |
18:41:42.70 |
+64:23:51.3 |
HIP 91950 |
30.89 |
| 2026-05-29 00:00 |
18:41:36.46 |
+64:24:20.6 |
HIP 91950 |
30.91 |
| 2026-05-29 12:00 |
18:41:30.18 |
+64:24:49.5 |
HIP 91950 |
30.96 |
| 2026-05-30 00:00 |
18:41:23.86 |
+64:25:18.0 |
HIP 91950 |
31.04 |
| 2026-05-30 12:00 |
18:41:17.51 |
+64:25:46.1 |
HIP 91950 |
31.15 |
| 2026-05-31 00:00 |
18:41:11.12 |
+64:26:13.8 |
HIP 91950 |
31.28 |
| 2026-05-31 12:00 |
18:41:04.69 |
+64:26:41.1 |
HIP 91950 |
31.45 |
| 2026-06-01 00:00 |
18:40:58.22 |
+64:27:08.0 |
HIP 91950 |
31.64 |
| 2026-06-01 12:00 |
18:40:51.72 |
+64:27:34.5 |
HIP 91950 |
31.86 |
| 2026-06-02 00:00 |
18:40:45.18 |
+64:28:00.7 |
HIP 91950 |
32.11 |