メタデータ
| 項目 |
値 |
| Designation |
C/2011 G1 (McNaught) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2011-09-16T09:53:33.371520Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:48Z |
| Obs used |
487 |
| NEO |
- |
| M1 |
14.400 |
| K1 |
5.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2011-11-20.0000000 |
| e |
1.00100017 |
| q (au) |
2.155142 |
| a (au) |
-2154.765225 |
| i (deg) |
162.233498 |
| Ω (om, deg) |
152.590960 |
| ω (w, deg) |
354.550126 |
| M (ma, deg) |
0.000636 |
等級
散乱 + 全体線形
$$
M_a = (13.505 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
13.505 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
1.000 |
| 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 |
| 2011-04-05 |
2011-06-17 |
+0.1582 |
-0.303 |
| 2011-10-25 |
2011-12-30 |
+31.4390 |
-11.639 |
| 2011-12-30 |
2012-03-18 |
-17.9862 |
+7.533 |
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 |
00:14:55.68 |
+12:48:54.4 |
HIP 1174 |
34.95 |
| 2026-07-29 12:00 |
00:14:53.62 |
+12:48:49.7 |
HIP 1174 |
34.82 |
| 2026-07-30 00:00 |
00:14:51.53 |
+12:48:44.7 |
HIP 1174 |
34.69 |
| 2026-07-30 12:00 |
00:14:49.41 |
+12:48:39.5 |
HIP 1174 |
34.56 |
| 2026-07-31 00:00 |
00:14:47.27 |
+12:48:34.1 |
HIP 1174 |
34.44 |
| 2026-07-31 12:00 |
00:14:45.10 |
+12:48:28.5 |
HIP 1174 |
34.32 |
| 2026-08-01 00:00 |
00:14:42.91 |
+12:48:22.7 |
HIP 1174 |
34.21 |
| 2026-08-01 12:00 |
00:14:40.69 |
+12:48:16.6 |
HIP 1174 |
34.10 |
| 2026-08-02 00:00 |
00:14:38.45 |
+12:48:10.4 |
HIP 1174 |
33.99 |
| 2026-08-02 12:00 |
00:14:36.18 |
+12:48:04.0 |
HIP 1174 |
33.89 |
| 2026-08-03 00:00 |
00:14:33.89 |
+12:47:57.4 |
HIP 1174 |
33.80 |
| 2026-08-03 12:00 |
00:14:31.57 |
+12:47:50.5 |
HIP 1174 |
33.71 |
| 2026-08-04 00:00 |
00:14:29.23 |
+12:47:43.5 |
HIP 1174 |
33.63 |
| 2026-08-04 12:00 |
00:14:26.87 |
+12:47:36.3 |
HIP 1174 |
33.56 |
| 2026-08-05 00:00 |
00:14:24.48 |
+12:47:28.8 |
HIP 1174 |
33.49 |
| 2026-08-05 12:00 |
00:14:22.07 |
+12:47:21.2 |
HIP 1174 |
33.43 |
| 2026-08-06 00:00 |
00:14:19.63 |
+12:47:13.3 |
HIP 1174 |
33.38 |
| 2026-08-06 12:00 |
00:14:17.17 |
+12:47:05.2 |
HIP 1038 |
33.10 |
| 2026-08-07 00:00 |
00:14:14.69 |
+12:46:57.0 |
HIP 1038 |
32.65 |
| 2026-08-07 12:00 |
00:14:12.18 |
+12:46:48.5 |
HIP 1038 |
32.19 |
| 2026-08-08 00:00 |
00:14:09.65 |
+12:46:39.8 |
HIP 1038 |
31.74 |
| 2026-08-08 12:00 |
00:14:07.10 |
+12:46:31.0 |
HIP 1038 |
31.28 |
| 2026-08-09 00:00 |
00:14:04.52 |
+12:46:21.9 |
HIP 1038 |
30.83 |
| 2026-08-09 12:00 |
00:14:01.92 |
+12:46:12.6 |
HIP 1038 |
30.37 |
| 2026-08-10 00:00 |
00:13:59.30 |
+12:46:03.1 |
HIP 1038 |
29.92 |
| 2026-08-10 12:00 |
00:13:56.66 |
+12:45:53.4 |
HIP 1038 |
29.47 |
| 2026-08-11 00:00 |
00:13:53.99 |
+12:45:43.5 |
HIP 1038 |
29.03 |
| 2026-08-11 12:00 |
00:13:51.30 |
+12:45:33.4 |
HIP 1038 |
28.58 |
| 2026-08-12 00:00 |
00:13:48.59 |
+12:45:23.1 |
HIP 1038 |
28.14 |
| 2026-08-12 12:00 |
00:13:45.86 |
+12:45:12.6 |
HIP 1038 |
27.71 |
| 2026-08-13 00:00 |
00:13:43.11 |
+12:45:01.9 |
HIP 1038 |
27.28 |
| 2026-08-13 12:00 |
00:13:40.33 |
+12:44:51.0 |
HIP 1038 |
26.86 |
| 2026-08-14 00:00 |
00:13:37.54 |
+12:44:39.9 |
HIP 1038 |
26.44 |
| 2026-08-14 12:00 |
00:13:34.72 |
+12:44:28.6 |
HIP 1038 |
26.03 |
| 2026-08-15 00:00 |
00:13:31.88 |
+12:44:17.1 |
HIP 1038 |
25.63 |
| 2026-08-15 12:00 |
00:13:29.02 |
+12:44:05.4 |
HIP 1038 |
25.24 |
| 2026-08-16 00:00 |
00:13:26.14 |
+12:43:53.6 |
HIP 1038 |
24.86 |
| 2026-08-16 12:00 |
00:13:23.25 |
+12:43:41.5 |
HIP 1038 |
24.50 |
| 2026-08-17 00:00 |
00:13:20.33 |
+12:43:29.2 |
HIP 1038 |
24.14 |
| 2026-08-17 12:00 |
00:13:17.39 |
+12:43:16.7 |
HIP 1038 |
23.80 |
| 2026-08-18 00:00 |
00:13:14.43 |
+12:43:04.0 |
HIP 1038 |
23.47 |
| 2026-08-18 12:00 |
00:13:11.45 |
+12:42:51.2 |
HIP 1038 |
23.16 |
| 2026-08-19 00:00 |
00:13:08.46 |
+12:42:38.1 |
HIP 1038 |
22.87 |