メタデータ
| 項目 |
値 |
| Designation |
C/2009 R1 (McNaught) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2010-07-02T16:16:32.168640Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:34Z |
| Obs used |
751 |
| NEO |
- |
| M1 |
9.900 |
| K1 |
6.750 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2010-04-11.0000000 |
| e |
1.00041320 |
| q (au) |
0.405087 |
| a (au) |
-980.359275 |
| i (deg) |
77.030765 |
| Ω (om, deg) |
322.622663 |
| ω (w, deg) |
130.693103 |
| M (ma, deg) |
-0.002655 |
等級
散乱 + 全体線形
$$
M_a = (10.751 + 4.547\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.751 |
| n |
4.547 |
| gf |
1.000 |
| gb |
-0.800 |
| 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
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 2009-07-20 |
2010-01-09 |
+20.6267 |
-13.127 |
| 2010-01-09 |
2010-06-05 |
-5.1167 |
-0.996 |
| 2010-06-05 |
2010-06-29 |
-1.4652 |
-1.713 |
log10 r = log10(太陽距離/AU)、Δ = 地球距離(AU)
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
23:16:20.96 |
-75:35:34.1 |
HIP 114925 |
3.78 |
| 2026-07-29 12:00 |
23:16:11.59 |
-75:36:09.0 |
HIP 114925 |
4.55 |
| 2026-07-30 00:00 |
23:16:02.14 |
-75:36:43.7 |
HIP 114925 |
5.33 |
| 2026-07-30 12:00 |
23:15:52.61 |
-75:37:18.0 |
HIP 114925 |
6.12 |
| 2026-07-31 00:00 |
23:15:42.99 |
-75:37:52.0 |
HIP 114925 |
6.92 |
| 2026-07-31 12:00 |
23:15:33.30 |
-75:38:25.8 |
HIP 114925 |
7.72 |
| 2026-08-01 00:00 |
23:15:23.54 |
-75:38:59.2 |
HIP 114925 |
8.53 |
| 2026-08-01 12:00 |
23:15:13.69 |
-75:39:32.4 |
HIP 114925 |
9.33 |
| 2026-08-02 00:00 |
23:15:03.77 |
-75:40:05.2 |
HIP 114925 |
10.14 |
| 2026-08-02 12:00 |
23:14:53.77 |
-75:40:37.7 |
HIP 114925 |
10.95 |
| 2026-08-03 00:00 |
23:14:43.70 |
-75:41:09.9 |
HIP 114925 |
11.76 |
| 2026-08-03 12:00 |
23:14:33.55 |
-75:41:41.8 |
HIP 114925 |
12.57 |
| 2026-08-04 00:00 |
23:14:23.33 |
-75:42:13.4 |
HIP 114925 |
13.38 |
| 2026-08-04 12:00 |
23:14:13.03 |
-75:42:44.7 |
HIP 114925 |
14.19 |
| 2026-08-05 00:00 |
23:14:02.67 |
-75:43:15.6 |
HIP 114925 |
15.00 |
| 2026-08-05 12:00 |
23:13:52.23 |
-75:43:46.2 |
HIP 114925 |
15.81 |
| 2026-08-06 00:00 |
23:13:41.72 |
-75:44:16.5 |
HIP 114925 |
16.62 |
| 2026-08-06 12:00 |
23:13:31.14 |
-75:44:46.5 |
HIP 114925 |
17.43 |
| 2026-08-07 00:00 |
23:13:20.49 |
-75:45:16.1 |
HIP 114324 |
17.47 |
| 2026-08-07 12:00 |
23:13:09.77 |
-75:45:45.4 |
HIP 114324 |
16.66 |
| 2026-08-08 00:00 |
23:12:58.99 |
-75:46:14.3 |
HIP 114324 |
15.85 |
| 2026-08-08 12:00 |
23:12:48.14 |
-75:46:42.9 |
HIP 114324 |
15.03 |
| 2026-08-09 00:00 |
23:12:37.22 |
-75:47:11.1 |
HIP 114324 |
14.22 |
| 2026-08-09 12:00 |
23:12:26.24 |
-75:47:39.0 |
HIP 114324 |
13.40 |
| 2026-08-10 00:00 |
23:12:15.19 |
-75:48:06.6 |
HIP 114324 |
12.59 |
| 2026-08-10 12:00 |
23:12:04.08 |
-75:48:33.8 |
HIP 114324 |
11.78 |
| 2026-08-11 00:00 |
23:11:52.91 |
-75:49:00.6 |
HIP 114324 |
10.96 |
| 2026-08-11 12:00 |
23:11:41.68 |
-75:49:27.1 |
HIP 114324 |
10.15 |
| 2026-08-12 00:00 |
23:11:30.38 |
-75:49:53.2 |
HIP 114324 |
9.34 |
| 2026-08-12 12:00 |
23:11:19.03 |
-75:50:18.9 |
HIP 114324 |
8.53 |
| 2026-08-13 00:00 |
23:11:07.62 |
-75:50:44.2 |
HIP 114324 |
7.72 |
| 2026-08-13 12:00 |
23:10:56.15 |
-75:51:09.2 |
HIP 114324 |
6.91 |
| 2026-08-14 00:00 |
23:10:44.63 |
-75:51:33.8 |
HIP 114324 |
6.10 |
| 2026-08-14 12:00 |
23:10:33.05 |
-75:51:58.1 |
HIP 114324 |
5.30 |
| 2026-08-15 00:00 |
23:10:21.42 |
-75:52:21.9 |
HIP 114324 |
4.49 |
| 2026-08-15 12:00 |
23:10:09.74 |
-75:52:45.4 |
HIP 114324 |
3.69 |
| 2026-08-16 00:00 |
23:09:58.00 |
-75:53:08.5 |
HIP 114324 |
2.90 |
| 2026-08-16 12:00 |
23:09:46.22 |
-75:53:31.2 |
HIP 114324 |
2.11 |
| 2026-08-17 00:00 |
23:09:34.38 |
-75:53:53.5 |
HIP 114324 |
1.36 |
| 2026-08-17 12:00 |
23:09:22.50 |
-75:54:15.4 |
HIP 114324 |
0.74 |
| 2026-08-18 00:00 |
23:09:10.57 |
-75:54:36.9 |
HIP 114324 |
0.75 |
| 2026-08-18 12:00 |
23:08:58.59 |
-75:54:58.0 |
HIP 114324 |
1.37 |
| 2026-08-19 00:00 |
23:08:46.57 |
-75:55:18.8 |
HIP 114324 |
2.12 |