67P/Churyumov-Gerasimenko
メタデータ
| 項目 | 値 |
|---|---|
| Designation | 67P/Churyumov-Gerasimenko |
| Type | P |
| Perihelion (tp_cal, UTC) | 2015-08-13T02:07:40.042560Z |
| Orbit solution date (soln_date, UTC) | 2024-02-01T08:49:50Z |
| Obs used | 8608 |
| NEO | Yes |
| M1 | 12.900 |
| K1 | 7.500 |
| PC | - |
オスキュレーティング軌道要素
| 項目 | 値 |
|---|---|
| Epoch (epoch_cal, TDB) | 2015-10-10.0000000 |
| e | 0.64090813 |
| q (au) | 1.243266 |
| a (au) | 3.462249 |
| i (deg) | 7.040295 |
| Ω (om, deg) | 50.135574 |
| ω (w, deg) | 12.798250 |
| M (ma, deg) | 8.859927 |
等級
散乱 + 全体線形
$$ M_a = (12.809 + 3.261\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
モデル定数
| 項目 | 値 |
|---|---|
| H0 | 12.809 |
| n | 3.261 |
| gf | 0.959 |
| gb | -0.500 |
| k | 0.800 |
| δ90 | 1.384 |
| 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 |
|---|---|---|---|
| 2021-02-02 | 2023-04-26 | -0.2979 | -0.513 |
log10 r = log10(太陽距離/AU)、Δ = 地球距離(AU)
ファインディングチャート
天体暦
| Date/Time (UTC) | RA (J2000) | Dec (J2000) | Nearest HIP | Dist from HIP (arcmin) |
|---|---|---|---|---|
| 2026-05-12 00:00 | 17:49:14.12 | -26:40:24.1 | HIP 87281 | 11.70 |
| 2026-05-12 12:00 | 17:48:58.58 | -26:40:40.3 | HIP 87281 | 15.15 |
| 2026-05-13 00:00 | 17:48:42.82 | -26:40:56.2 | HIP 87163 | 17.87 |
| 2026-05-13 12:00 | 17:48:26.87 | -26:41:11.8 | HIP 87163 | 17.30 |
| 2026-05-14 00:00 | 17:48:10.71 | -26:41:27.2 | HIP 87163 | 17.47 |
| 2026-05-14 12:00 | 17:47:54.35 | -26:41:42.3 | HIP 87163 | 18.38 |
| 2026-05-15 00:00 | 17:47:37.79 | -26:41:57.1 | HIP 87163 | 19.96 |
| 2026-05-15 12:00 | 17:47:21.03 | -26:42:11.7 | HIP 87163 | 22.09 |
| 2026-05-16 00:00 | 17:47:04.07 | -26:42:25.9 | HIP 86924 | 19.04 |
| 2026-05-16 12:00 | 17:46:46.92 | -26:42:39.8 | HIP 86924 | 15.34 |
| 2026-05-17 00:00 | 17:46:29.58 | -26:42:53.4 | HIP 86924 | 11.69 |
| 2026-05-17 12:00 | 17:46:12.05 | -26:43:06.7 | HIP 86924 | 8.21 |
| 2026-05-18 00:00 | 17:45:54.33 | -26:43:19.7 | HIP 86924 | 5.35 |
| 2026-05-18 12:00 | 17:45:36.43 | -26:43:32.3 | HIP 86924 | 4.62 |
| 2026-05-19 00:00 | 17:45:18.35 | -26:43:44.6 | HIP 86924 | 6.81 |
| 2026-05-19 12:00 | 17:45:00.08 | -26:43:56.6 | HIP 86858 | 8.98 |
| 2026-05-20 00:00 | 17:44:41.63 | -26:44:08.2 | HIP 86858 | 8.95 |
| 2026-05-20 12:00 | 17:44:23.02 | -26:44:19.5 | HIP 86858 | 10.67 |
| 2026-05-21 00:00 | 17:44:04.22 | -26:44:30.4 | HIP 86858 | 13.53 |
| 2026-05-21 12:00 | 17:43:45.26 | -26:44:40.9 | HIP 86858 | 16.98 |
| 2026-05-22 00:00 | 17:43:26.13 | -26:44:51.1 | HIP 86633 | 18.98 |
| 2026-05-22 12:00 | 17:43:06.83 | -26:45:00.9 | HIP 86633 | 14.88 |
| 2026-05-23 00:00 | 17:42:47.37 | -26:45:10.3 | HIP 86633 | 10.92 |
| 2026-05-23 12:00 | 17:42:27.75 | -26:45:19.4 | HIP 86633 | 7.38 |
| 2026-05-24 00:00 | 17:42:07.98 | -26:45:28.0 | HIP 86633 | 5.30 |
| 2026-05-24 12:00 | 17:41:48.04 | -26:45:36.3 | HIP 86633 | 6.41 |
| 2026-05-25 00:00 | 17:41:27.96 | -26:45:44.1 | HIP 86633 | 9.71 |
| 2026-05-25 12:00 | 17:41:07.73 | -26:45:51.6 | HIP 86633 | 13.74 |
| 2026-05-26 00:00 | 17:40:47.35 | -26:45:58.6 | HIP 86633 | 18.03 |
| 2026-05-26 12:00 | 17:40:26.82 | -26:46:05.2 | HIP 86385 | 20.70 |
| 2026-05-27 00:00 | 17:40:06.16 | -26:46:11.4 | HIP 86385 | 16.77 |
| 2026-05-27 12:00 | 17:39:45.35 | -26:46:17.2 | HIP 86385 | 13.28 |
| 2026-05-28 00:00 | 17:39:24.41 | -26:46:22.5 | HIP 86385 | 10.69 |
| 2026-05-28 12:00 | 17:39:03.34 | -26:46:27.4 | HIP 86385 | 9.80 |
| 2026-05-29 00:00 | 17:38:42.13 | -26:46:31.9 | HIP 86385 | 11.07 |
| 2026-05-29 12:00 | 17:38:20.80 | -26:46:36.0 | HIP 86265 | 10.05 |
| 2026-05-30 00:00 | 17:37:59.35 | -26:46:39.5 | HIP 86265 | 5.32 |
| 2026-05-30 12:00 | 17:37:37.77 | -26:46:42.7 | HIP 86265 | 1.22 |
| 2026-05-31 00:00 | 17:37:16.08 | -26:46:45.4 | HIP 86265 | 4.62 |
| 2026-05-31 12:00 | 17:36:54.27 | -26:46:47.6 | HIP 86265 | 9.41 |
| 2026-06-01 00:00 | 17:36:32.34 | -26:46:49.3 | HIP 86265 | 14.28 |
| 2026-06-01 12:00 | 17:36:10.31 | -26:46:50.6 | HIP 86110 | 17.70 |
| 2026-06-02 00:00 | 17:35:48.17 | -26:46:51.5 | HIP 86020 | 14.04 |