メタデータ
| 項目 |
値 |
| Designation |
C/2010 G2 (Hill) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2011-09-02T01:12:35.795520Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:42Z |
| Obs used |
4103 |
| NEO |
- |
| M1 |
10.800 |
| K1 |
6.250 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2011-07-30.0000000 |
| e |
0.97940713 |
| q (au) |
1.980774 |
| a (au) |
96.187351 |
| i (deg) |
103.745283 |
| Ω (om, deg) |
246.781006 |
| ω (w, deg) |
137.425281 |
| M (ma, deg) |
359.964425 |
等級
散乱 + 全体線形
$$
M_a = (10.346 + 2.260\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
10.346 |
| n |
2.260 |
| gf |
0.993 |
| gb |
-0.971 |
| k |
1.000 |
| δ90 |
9.997 |
| 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 |
| 2010-04-10 |
2010-08-28 |
+14.9148 |
-10.749 |
| 2010-08-28 |
2011-05-04 |
-7.9772 |
+3.754 |
| 2011-05-04 |
2011-09-02 |
+19.9398 |
-7.392 |
| 2011-09-02 |
2012-01-01 |
+7.3113 |
-2.940 |
| 2012-01-01 |
2013-03-06 |
+3.5605 |
-2.360 |
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 |
00:48:05.57 |
-87:08:24.0 |
HIP 5953 |
23.83 |
| 2026-07-29 12:00 |
00:47:33.40 |
-87:09:18.3 |
HIP 5953 |
23.67 |
| 2026-07-30 00:00 |
00:47:00.34 |
-87:10:12.4 |
HIP 5953 |
23.57 |
| 2026-07-30 12:00 |
00:46:26.39 |
-87:11:06.2 |
HIP 5953 |
23.51 |
| 2026-07-31 00:00 |
00:45:51.53 |
-87:11:59.8 |
HIP 5953 |
23.51 |
| 2026-07-31 12:00 |
00:45:15.76 |
-87:12:53.0 |
HIP 5953 |
23.55 |
| 2026-08-01 00:00 |
00:44:39.06 |
-87:13:46.0 |
HIP 5953 |
23.64 |
| 2026-08-01 12:00 |
00:44:01.43 |
-87:14:38.6 |
HIP 5953 |
23.78 |
| 2026-08-02 00:00 |
00:43:22.85 |
-87:15:31.0 |
HIP 5953 |
23.97 |
| 2026-08-02 12:00 |
00:42:43.32 |
-87:16:23.0 |
HIP 903 |
23.51 |
| 2026-08-03 00:00 |
00:42:02.83 |
-87:17:14.7 |
HIP 903 |
22.71 |
| 2026-08-03 12:00 |
00:41:21.37 |
-87:18:06.0 |
HIP 903 |
21.93 |
| 2026-08-04 00:00 |
00:40:38.93 |
-87:18:57.0 |
HIP 903 |
21.17 |
| 2026-08-04 12:00 |
00:39:55.49 |
-87:19:47.7 |
HIP 903 |
20.41 |
| 2026-08-05 00:00 |
00:39:11.06 |
-87:20:38.0 |
HIP 903 |
19.68 |
| 2026-08-05 12:00 |
00:38:25.62 |
-87:21:27.9 |
HIP 903 |
18.96 |
| 2026-08-06 00:00 |
00:37:39.17 |
-87:22:17.4 |
HIP 903 |
18.26 |
| 2026-08-06 12:00 |
00:36:51.69 |
-87:23:06.6 |
HIP 903 |
17.58 |
| 2026-08-07 00:00 |
00:36:03.18 |
-87:23:55.4 |
HIP 903 |
16.92 |
| 2026-08-07 12:00 |
00:35:13.64 |
-87:24:43.7 |
HIP 903 |
16.30 |
| 2026-08-08 00:00 |
00:34:23.04 |
-87:25:31.7 |
HIP 903 |
15.70 |
| 2026-08-08 12:00 |
00:33:31.40 |
-87:26:19.2 |
HIP 903 |
15.14 |
| 2026-08-09 00:00 |
00:32:38.69 |
-87:27:06.2 |
HIP 903 |
14.61 |
| 2026-08-09 12:00 |
00:31:44.92 |
-87:27:52.9 |
HIP 1649 |
14.03 |
| 2026-08-10 00:00 |
00:30:50.08 |
-87:28:39.1 |
HIP 1649 |
13.07 |
| 2026-08-10 12:00 |
00:29:54.16 |
-87:29:24.8 |
HIP 1649 |
12.11 |
| 2026-08-11 00:00 |
00:28:57.16 |
-87:30:10.0 |
HIP 1649 |
11.15 |
| 2026-08-11 12:00 |
00:27:59.08 |
-87:30:54.8 |
HIP 1649 |
10.20 |
| 2026-08-12 00:00 |
00:26:59.90 |
-87:31:39.0 |
HIP 1649 |
9.26 |
| 2026-08-12 12:00 |
00:25:59.64 |
-87:32:22.8 |
HIP 1649 |
8.34 |
| 2026-08-13 00:00 |
00:24:58.27 |
-87:33:06.0 |
HIP 1649 |
7.42 |
| 2026-08-13 12:00 |
00:23:55.82 |
-87:33:48.7 |
HIP 1649 |
6.53 |
| 2026-08-14 00:00 |
00:22:52.26 |
-87:34:30.9 |
HIP 1649 |
5.67 |
| 2026-08-14 12:00 |
00:21:47.61 |
-87:35:12.6 |
HIP 1649 |
4.86 |
| 2026-08-15 00:00 |
00:20:41.85 |
-87:35:53.6 |
HIP 1649 |
4.13 |
| 2026-08-15 12:00 |
00:19:35.00 |
-87:36:34.2 |
HIP 1649 |
3.52 |
| 2026-08-16 00:00 |
00:18:27.06 |
-87:37:14.1 |
HIP 1649 |
3.11 |
| 2026-08-16 12:00 |
00:17:18.02 |
-87:37:53.5 |
HIP 1649 |
2.98 |
| 2026-08-17 00:00 |
00:16:07.88 |
-87:38:32.2 |
HIP 1649 |
3.17 |
| 2026-08-17 12:00 |
00:14:56.66 |
-87:39:10.4 |
HIP 1649 |
3.62 |
| 2026-08-18 00:00 |
00:13:44.35 |
-87:39:47.9 |
HIP 1649 |
4.25 |
| 2026-08-18 12:00 |
00:12:30.96 |
-87:40:24.8 |
HIP 1649 |
5.00 |
| 2026-08-19 00:00 |
00:11:16.50 |
-87:41:01.1 |
HIP 1649 |
5.81 |