64P/Swift-Gehrels
メタデータ
| 項目 | 値 |
|---|---|
| Designation | 64P/Swift-Gehrels |
| Type | P |
| Perihelion (tp_cal, UTC) | 2018-11-03T21:53:15.495360Z |
| Orbit solution date (soln_date, UTC) | 2023-12-21T08:26:18Z |
| Obs used | 3436 |
| NEO | - |
| M1 | 14.500 |
| K1 | 6.000 |
| PC | - |
オスキュレーティング軌道要素
| 項目 | 値 |
|---|---|
| Epoch (epoch_cal, TDB) | 2017-12-09.0000000 |
| e | 0.68732017 |
| q (au) | 1.393350 |
| a (au) | 4.456157 |
| i (deg) | 8.948393 |
| Ω (om, deg) | 300.000979 |
| ω (w, deg) | 97.144197 |
| M (ma, deg) | 325.433022 |
等級
散乱 + 全体線形
$$ M_a = (12.975 + 2.694\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
モデル定数
| 項目 | 値 |
|---|---|
| H0 | 12.975 |
| n | 2.694 |
| gf | 1.000 |
| gb | -0.500 |
| k | 1.000 |
| 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 |
|---|---|---|---|
| 2018-05-25 | 2018-08-18 | +18.2376 | -3.210 |
| 2018-08-18 | 2018-11-03 | +26.1678 | -4.382 |
| 2018-11-03 | 2019-05-06 | +1.4814 | -1.754 |
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) |
|---|---|---|---|---|
| 2026-02-03 00:00 | 16:51:19.01 | -29:13:19.6 | HIP 82492 | 11.67 |
| 2026-02-03 12:00 | 16:51:36.25 | -29:14:06.2 | HIP 82492 | 10.49 |
| 2026-02-04 00:00 | 16:51:53.39 | -29:14:52.6 | HIP 82492 | 10.63 |
| 2026-02-04 12:00 | 16:52:10.42 | -29:15:39.0 | HIP 82492 | 12.03 |
| 2026-02-05 00:00 | 16:52:27.34 | -29:16:25.2 | HIP 82492 | 14.31 |
| 2026-02-05 12:00 | 16:52:44.15 | -29:17:11.3 | HIP 82492 | 17.10 |
| 2026-02-06 00:00 | 16:53:00.84 | -29:17:57.4 | HIP 82492 | 20.17 |
| 2026-02-06 12:00 | 16:53:17.42 | -29:18:43.3 | HIP 82742 | 18.62 |
| 2026-02-07 00:00 | 16:53:33.88 | -29:19:29.1 | HIP 82742 | 15.00 |
| 2026-02-07 12:00 | 16:53:50.23 | -29:20:14.8 | HIP 82742 | 11.45 |
| 2026-02-08 00:00 | 16:54:06.46 | -29:21:00.4 | HIP 82742 | 8.02 |
| 2026-02-08 12:00 | 16:54:22.57 | -29:21:45.9 | HIP 82742 | 4.87 |
| 2026-02-09 00:00 | 16:54:38.56 | -29:22:31.2 | HIP 82742 | 3.00 |
| 2026-02-09 12:00 | 16:54:54.43 | -29:23:16.5 | HIP 82742 | 4.42 |
| 2026-02-10 00:00 | 16:55:10.18 | -29:24:01.7 | HIP 82782 | 5.92 |
| 2026-02-10 12:00 | 16:55:25.81 | -29:24:46.7 | HIP 82782 | 8.14 |
| 2026-02-11 00:00 | 16:55:41.31 | -29:25:31.6 | HIP 82821 | 9.13 |
| 2026-02-11 12:00 | 16:55:56.68 | -29:26:16.5 | HIP 82821 | 11.03 |
| 2026-02-12 00:00 | 16:56:11.93 | -29:27:01.2 | HIP 82821 | 13.52 |
| 2026-02-12 12:00 | 16:56:27.05 | -29:27:45.8 | HIP 82821 | 16.33 |
| 2026-02-13 00:00 | 16:56:42.04 | -29:28:30.3 | HIP 82821 | 19.29 |
| 2026-02-13 12:00 | 16:56:56.91 | -29:29:14.7 | HIP 82821 | 22.34 |
| 2026-02-14 00:00 | 16:57:11.63 | -29:29:59.0 | HIP 82821 | 25.43 |
| 2026-02-14 12:00 | 16:57:26.23 | -29:30:43.1 | HIP 82821 | 28.54 |
| 2026-02-15 00:00 | 16:57:40.69 | -29:31:27.2 | HIP 82821 | 31.66 |
| 2026-02-15 12:00 | 16:57:55.02 | -29:32:11.1 | HIP 82821 | 34.76 |
| 2026-02-16 00:00 | 16:58:09.21 | -29:32:55.0 | HIP 83080 | 34.80 |
| 2026-02-16 12:00 | 16:58:23.27 | -29:33:38.7 | HIP 83080 | 33.70 |
| 2026-02-17 00:00 | 16:58:37.18 | -29:34:22.3 | HIP 83258 | 31.90 |
| 2026-02-17 12:00 | 16:58:50.96 | -29:35:05.8 | HIP 83258 | 28.83 |
| 2026-02-18 00:00 | 16:59:04.60 | -29:35:49.2 | HIP 83258 | 25.78 |
| 2026-02-18 12:00 | 16:59:18.09 | -29:36:32.5 | HIP 83258 | 22.77 |
| 2026-02-19 00:00 | 16:59:31.44 | -29:37:15.6 | HIP 83258 | 19.79 |
| 2026-02-19 12:00 | 16:59:44.65 | -29:37:58.7 | HIP 83258 | 16.84 |
| 2026-02-20 00:00 | 16:59:57.71 | -29:38:41.6 | HIP 83258 | 13.94 |
| 2026-02-20 12:00 | 17:00:10.62 | -29:39:24.4 | HIP 83258 | 11.07 |
| 2026-02-21 00:00 | 17:00:23.39 | -29:40:07.1 | HIP 83258 | 8.26 |
| 2026-02-21 12:00 | 17:00:36.01 | -29:40:49.7 | HIP 83258 | 5.55 |
| 2026-02-22 00:00 | 17:00:48.48 | -29:41:32.2 | HIP 83258 | 3.07 |
| 2026-02-22 12:00 | 17:01:00.80 | -29:42:14.6 | HIP 83258 | 1.95 |
| 2026-02-23 00:00 | 17:01:12.97 | -29:42:56.8 | HIP 83280 | 1.89 |
| 2026-02-23 12:00 | 17:01:24.99 | -29:43:39.0 | HIP 83280 | 3.73 |
| 2026-02-24 00:00 | 17:01:36.85 | -29:44:21.0 | HIP 83280 | 6.21 |