メタデータ
| 項目 |
値 |
| Designation |
C/2009 G1 (STEREO) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2009-04-16T12:08:09.119040Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:30Z |
| Obs used |
119 |
| NEO |
- |
| M1 |
9.100 |
| K1 |
17.250 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2009-05-09.0000000 |
| e |
0.99767848 |
| q (au) |
1.128742 |
| a (au) |
486.208569 |
| i (deg) |
108.310256 |
| Ω (om, deg) |
120.634994 |
| ω (w, deg) |
175.444080 |
| M (ma, deg) |
0.002068 |
等級
散乱 + 全体線形
$$
M_a = (9.287 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
9.287 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.965 |
| 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) |
| 2026-07-29 00:00 |
08:21:29.52 |
-03:45:50.4 |
HIP 41084 |
36.05 |
| 2026-07-29 12:00 |
08:21:32.56 |
-03:45:59.5 |
HIP 41084 |
35.47 |
| 2026-07-30 00:00 |
08:21:35.61 |
-03:46:08.7 |
HIP 41084 |
34.90 |
| 2026-07-30 12:00 |
08:21:38.65 |
-03:46:18.1 |
HIP 41084 |
34.34 |
| 2026-07-31 00:00 |
08:21:41.69 |
-03:46:27.6 |
HIP 41084 |
33.78 |
| 2026-07-31 12:00 |
08:21:44.73 |
-03:46:37.3 |
HIP 41084 |
33.23 |
| 2026-08-01 00:00 |
08:21:47.76 |
-03:46:47.2 |
HIP 41084 |
32.69 |
| 2026-08-01 12:00 |
08:21:50.79 |
-03:46:57.1 |
HIP 41084 |
32.16 |
| 2026-08-02 00:00 |
08:21:53.82 |
-03:47:07.3 |
HIP 41084 |
31.63 |
| 2026-08-02 12:00 |
08:21:56.85 |
-03:47:17.5 |
HIP 41084 |
31.11 |
| 2026-08-03 00:00 |
08:21:59.87 |
-03:47:28.0 |
HIP 41084 |
30.60 |
| 2026-08-03 12:00 |
08:22:02.89 |
-03:47:38.5 |
HIP 41084 |
30.11 |
| 2026-08-04 00:00 |
08:22:05.91 |
-03:47:49.2 |
HIP 41084 |
29.62 |
| 2026-08-04 12:00 |
08:22:08.92 |
-03:48:00.1 |
HIP 41084 |
29.14 |
| 2026-08-05 00:00 |
08:22:11.93 |
-03:48:11.1 |
HIP 41084 |
28.67 |
| 2026-08-05 12:00 |
08:22:14.94 |
-03:48:22.2 |
HIP 41084 |
28.21 |
| 2026-08-06 00:00 |
08:22:17.94 |
-03:48:33.5 |
HIP 41084 |
27.77 |
| 2026-08-06 12:00 |
08:22:20.93 |
-03:48:44.9 |
HIP 41084 |
27.34 |
| 2026-08-07 00:00 |
08:22:23.92 |
-03:48:56.5 |
HIP 41084 |
26.92 |
| 2026-08-07 12:00 |
08:22:26.91 |
-03:49:08.2 |
HIP 41084 |
26.52 |
| 2026-08-08 00:00 |
08:22:29.89 |
-03:49:20.0 |
HIP 41084 |
26.13 |
| 2026-08-08 12:00 |
08:22:32.87 |
-03:49:31.9 |
HIP 41084 |
25.75 |
| 2026-08-09 00:00 |
08:22:35.84 |
-03:49:44.1 |
HIP 41084 |
25.40 |
| 2026-08-09 12:00 |
08:22:38.80 |
-03:49:56.3 |
HIP 41084 |
25.05 |
| 2026-08-10 00:00 |
08:22:41.76 |
-03:50:08.7 |
HIP 41084 |
24.73 |
| 2026-08-10 12:00 |
08:22:44.71 |
-03:50:21.2 |
HIP 41084 |
24.42 |
| 2026-08-11 00:00 |
08:22:47.66 |
-03:50:33.8 |
HIP 41084 |
24.13 |
| 2026-08-11 12:00 |
08:22:50.60 |
-03:50:46.6 |
HIP 41084 |
23.86 |
| 2026-08-12 00:00 |
08:22:53.53 |
-03:50:59.5 |
HIP 41084 |
23.61 |
| 2026-08-12 12:00 |
08:22:56.46 |
-03:51:12.5 |
HIP 41084 |
23.38 |
| 2026-08-13 00:00 |
08:22:59.38 |
-03:51:25.7 |
HIP 41084 |
23.17 |
| 2026-08-13 12:00 |
08:23:02.29 |
-03:51:38.9 |
HIP 41084 |
22.99 |
| 2026-08-14 00:00 |
08:23:05.19 |
-03:51:52.4 |
HIP 41084 |
22.82 |
| 2026-08-14 12:00 |
08:23:08.08 |
-03:52:05.9 |
HIP 41084 |
22.67 |
| 2026-08-15 00:00 |
08:23:10.97 |
-03:52:19.6 |
HIP 41211 |
22.21 |
| 2026-08-15 12:00 |
08:23:13.85 |
-03:52:33.3 |
HIP 41211 |
21.61 |
| 2026-08-16 00:00 |
08:23:16.72 |
-03:52:47.2 |
HIP 41211 |
21.03 |
| 2026-08-16 12:00 |
08:23:19.58 |
-03:53:01.3 |
HIP 41211 |
20.46 |
| 2026-08-17 00:00 |
08:23:22.44 |
-03:53:15.4 |
HIP 41211 |
19.90 |
| 2026-08-17 12:00 |
08:23:25.28 |
-03:53:29.7 |
HIP 41211 |
19.36 |
| 2026-08-18 00:00 |
08:23:28.11 |
-03:53:44.0 |
HIP 41211 |
18.83 |
| 2026-08-18 12:00 |
08:23:30.94 |
-03:53:58.5 |
HIP 41211 |
18.32 |
| 2026-08-19 00:00 |
08:23:33.75 |
-03:54:13.1 |
HIP 41211 |
17.84 |