メタデータ
| 項目 |
値 |
| Designation |
205P/Giacobini |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2015-05-14T00:01:56.562240Z |
| Orbit solution date (soln_date, UTC) |
2023-07-20T15:02:32Z |
| Obs used |
564 |
| NEO |
- |
| M1 |
14.000 |
| K1 |
9.750 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2014-02-19.0000000 |
| e |
0.56693106 |
| q (au) |
1.536180 |
| a (au) |
3.547195 |
| i (deg) |
15.287237 |
| Ω (om, deg) |
179.624626 |
| ω (w, deg) |
154.256561 |
| M (ma, deg) |
293.759426 |
等級
散乱 + 全体線形
$$
M_a = (14.018 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
14.018 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.635 |
| 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 |
| 2021-05-14 |
2021-11-14 |
+11.4698 |
-2.714 |
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) |
| 2026-05-12 00:00 |
10:51:51.77 |
+05:02:08.6 |
HIP 53165 |
10.80 |
| 2026-05-12 12:00 |
10:51:50.30 |
+05:03:01.6 |
HIP 53165 |
11.34 |
| 2026-05-13 00:00 |
10:51:49.02 |
+05:03:53.3 |
HIP 53032 |
11.73 |
| 2026-05-13 12:00 |
10:51:47.93 |
+05:04:43.9 |
HIP 53032 |
11.63 |
| 2026-05-14 00:00 |
10:51:47.02 |
+05:05:33.2 |
HIP 53032 |
11.64 |
| 2026-05-14 12:00 |
10:51:46.30 |
+05:06:21.4 |
HIP 53032 |
11.75 |
| 2026-05-15 00:00 |
10:51:45.76 |
+05:07:08.3 |
HIP 53032 |
11.95 |
| 2026-05-15 12:00 |
10:51:45.41 |
+05:07:53.9 |
HIP 53032 |
12.22 |
| 2026-05-16 00:00 |
10:51:45.25 |
+05:08:38.4 |
HIP 53032 |
12.56 |
| 2026-05-16 12:00 |
10:51:45.27 |
+05:09:21.6 |
HIP 53032 |
12.96 |
| 2026-05-17 00:00 |
10:51:45.47 |
+05:10:03.6 |
HIP 53032 |
13.42 |
| 2026-05-17 12:00 |
10:51:45.86 |
+05:10:44.4 |
HIP 53032 |
13.91 |
| 2026-05-18 00:00 |
10:51:46.43 |
+05:11:24.0 |
HIP 53032 |
14.45 |
| 2026-05-18 12:00 |
10:51:47.18 |
+05:12:02.3 |
HIP 53032 |
15.01 |
| 2026-05-19 00:00 |
10:51:48.12 |
+05:12:39.4 |
HIP 53032 |
15.60 |
| 2026-05-19 12:00 |
10:51:49.24 |
+05:13:15.3 |
HIP 53032 |
16.22 |
| 2026-05-20 00:00 |
10:51:50.54 |
+05:13:50.0 |
HIP 53032 |
16.86 |
| 2026-05-20 12:00 |
10:51:52.03 |
+05:14:23.5 |
HIP 53032 |
17.51 |
| 2026-05-21 00:00 |
10:51:53.69 |
+05:14:55.8 |
HIP 53165 |
17.91 |
| 2026-05-21 12:00 |
10:51:55.54 |
+05:15:26.9 |
HIP 53165 |
18.09 |
| 2026-05-22 00:00 |
10:51:57.57 |
+05:15:56.7 |
HIP 53165 |
18.25 |
| 2026-05-22 12:00 |
10:51:59.77 |
+05:16:25.4 |
HIP 53165 |
18.40 |
| 2026-05-23 00:00 |
10:52:02.15 |
+05:16:52.9 |
HIP 53165 |
18.54 |
| 2026-05-23 12:00 |
10:52:04.72 |
+05:17:19.2 |
HIP 53165 |
18.68 |
| 2026-05-24 00:00 |
10:52:07.46 |
+05:17:44.3 |
HIP 53165 |
18.81 |
| 2026-05-24 12:00 |
10:52:10.37 |
+05:18:08.2 |
HIP 53165 |
18.94 |
| 2026-05-25 00:00 |
10:52:13.46 |
+05:18:30.9 |
HIP 53165 |
19.08 |
| 2026-05-25 12:00 |
10:52:16.73 |
+05:18:52.4 |
HIP 53165 |
19.22 |
| 2026-05-26 00:00 |
10:52:20.17 |
+05:19:12.8 |
HIP 53165 |
19.38 |
| 2026-05-26 12:00 |
10:52:23.79 |
+05:19:32.0 |
HIP 53165 |
19.55 |
| 2026-05-27 00:00 |
10:52:27.58 |
+05:19:50.0 |
HIP 53165 |
19.74 |
| 2026-05-27 12:00 |
10:52:31.54 |
+05:20:06.8 |
HIP 53165 |
19.96 |
| 2026-05-28 00:00 |
10:52:35.67 |
+05:20:22.5 |
HIP 53165 |
20.22 |
| 2026-05-28 12:00 |
10:52:39.98 |
+05:20:37.1 |
HIP 53165 |
20.50 |
| 2026-05-29 00:00 |
10:52:44.45 |
+05:20:50.4 |
HIP 53165 |
20.83 |
| 2026-05-29 12:00 |
10:52:49.10 |
+05:21:02.7 |
HIP 53165 |
21.20 |
| 2026-05-30 00:00 |
10:52:53.92 |
+05:21:13.7 |
HIP 53165 |
21.62 |
| 2026-05-30 12:00 |
10:52:58.90 |
+05:21:23.7 |
HIP 53165 |
22.09 |
| 2026-05-31 00:00 |
10:53:04.05 |
+05:21:32.5 |
HIP 53165 |
22.62 |
| 2026-05-31 12:00 |
10:53:09.37 |
+05:21:40.1 |
HIP 53165 |
23.20 |
| 2026-06-01 00:00 |
10:53:14.85 |
+05:21:46.7 |
HIP 53165 |
23.85 |
| 2026-06-01 12:00 |
10:53:20.51 |
+05:21:52.0 |
HIP 53165 |
24.56 |
| 2026-06-02 00:00 |
10:53:26.32 |
+05:21:56.3 |
HIP 53212 |
24.95 |