67P/Churyumov-Gerasimenko
メタデータ
| 項目 | 値 |
|---|---|
| Designation | 67P/Churyumov-Gerasimenko |
| Type | P |
| Perihelion (tp_cal, UTC) | 2015-08-13T02:07:40.033920Z |
| Orbit solution date (soln_date, UTC) | 2026-09-04T10:25:07Z |
| Obs used | 8610 |
| 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) |
|---|---|---|---|---|
| 2026-09-25 00:00 | 17:00:33.44 | -25:43:36.3 | HIP 83301 | 29.03 |
| 2026-09-25 12:00 | 17:00:48.30 | -25:43:43.9 | HIP 83301 | 27.91 |
| 2026-09-26 00:00 | 17:01:03.34 | -25:43:51.7 | HIP 83301 | 27.16 |
| 2026-09-26 12:00 | 17:01:18.58 | -25:43:59.7 | HIP 83301 | 26.82 |
| 2026-09-27 00:00 | 17:01:34.00 | -25:44:08.0 | HIP 83301 | 26.92 |
| 2026-09-27 12:00 | 17:01:49.61 | -25:44:16.5 | HIP 83301 | 27.48 |
| 2026-09-28 00:00 | 17:02:05.40 | -25:44:25.2 | HIP 83508 | 26.12 |
| 2026-09-28 12:00 | 17:02:21.38 | -25:44:34.2 | HIP 83508 | 22.56 |
| 2026-09-29 00:00 | 17:02:37.54 | -25:44:43.4 | HIP 83508 | 18.97 |
| 2026-09-29 12:00 | 17:02:53.89 | -25:44:52.7 | HIP 83508 | 15.37 |
| 2026-09-30 00:00 | 17:03:10.41 | -25:45:02.3 | HIP 83508 | 11.78 |
| 2026-09-30 12:00 | 17:03:27.12 | -25:45:12.1 | HIP 83508 | 8.29 |
| 2026-10-01 00:00 | 17:03:44.01 | -25:45:22.1 | HIP 83508 | 5.15 |
| 2026-10-01 12:00 | 17:04:01.08 | -25:45:32.3 | HIP 83508 | 3.66 |
| 2026-10-02 00:00 | 17:04:18.33 | -25:45:42.7 | HIP 83508 | 5.50 |
| 2026-10-02 12:00 | 17:04:35.76 | -25:45:53.3 | HIP 83566 | 7.39 |
| 2026-10-03 00:00 | 17:04:53.36 | -25:46:04.0 | HIP 83566 | 7.68 |
| 2026-10-03 12:00 | 17:05:11.14 | -25:46:15.0 | HIP 83566 | 9.78 |
| 2026-10-04 00:00 | 17:05:29.10 | -25:46:26.1 | HIP 83566 | 12.85 |
| 2026-10-04 12:00 | 17:05:47.23 | -25:46:37.4 | HIP 83566 | 16.39 |
| 2026-10-05 00:00 | 17:06:05.53 | -25:46:48.8 | HIP 83566 | 20.17 |
| 2026-10-05 12:00 | 17:06:24.01 | -25:47:00.4 | HIP 83615 | 22.99 |
| 2026-10-06 00:00 | 17:06:42.66 | -25:47:12.2 | HIP 83823 | 25.03 |
| 2026-10-06 12:00 | 17:07:01.49 | -25:47:24.1 | HIP 83823 | 22.83 |
| 2026-10-07 00:00 | 17:07:20.48 | -25:47:36.2 | HIP 83823 | 21.25 |
| 2026-10-07 12:00 | 17:07:39.65 | -25:47:48.4 | HIP 83823 | 20.46 |
| 2026-10-08 00:00 | 17:07:58.98 | -25:48:00.8 | HIP 83823 | 20.57 |
| 2026-10-08 12:00 | 17:08:18.48 | -25:48:13.3 | HIP 83823 | 21.60 |
| 2026-10-09 00:00 | 17:08:38.15 | -25:48:25.9 | HIP 83823 | 23.44 |
| 2026-10-09 12:00 | 17:08:57.98 | -25:48:38.6 | HIP 83823 | 25.94 |
| 2026-10-10 00:00 | 17:09:17.98 | -25:48:51.5 | HIP 83823 | 28.95 |
| 2026-10-10 12:00 | 17:09:38.14 | -25:49:04.5 | HIP 83823 | 32.34 |
| 2026-10-11 00:00 | 17:09:58.47 | -25:49:17.5 | HIP 84160 | 33.50 |
| 2026-10-11 12:00 | 17:10:18.96 | -25:49:30.7 | HIP 84160 | 29.21 |
| 2026-10-12 00:00 | 17:10:39.61 | -25:49:44.0 | HIP 84160 | 25.00 |
| 2026-10-12 12:00 | 17:11:00.41 | -25:49:57.4 | HIP 84160 | 20.96 |
| 2026-10-13 00:00 | 17:11:21.38 | -25:50:10.9 | HIP 84160 | 17.21 |
| 2026-10-13 12:00 | 17:11:42.51 | -25:50:24.5 | HIP 84160 | 14.06 |
| 2026-10-14 00:00 | 17:12:03.79 | -25:50:38.1 | HIP 84160 | 12.00 |
| 2026-10-14 12:00 | 17:12:25.23 | -25:50:51.9 | HIP 84160 | 11.69 |
| 2026-10-15 00:00 | 17:12:46.82 | -25:51:05.6 | HIP 84160 | 13.28 |
| 2026-10-15 12:00 | 17:13:08.57 | -25:51:19.5 | HIP 84160 | 16.25 |
| 2026-10-16 00:00 | 17:13:30.47 | -25:51:33.4 | HIP 84356 | 17.37 |