65P/Gunn
メタデータ
| 項目 | 値 |
|---|---|
| Designation | 65P/Gunn |
| Type | P |
| Perihelion (tp_cal, UTC) | 2017-10-17T19:28:05.684160Z |
| Orbit solution date (soln_date, UTC) | 2025-12-03T12:36:51Z |
| Obs used | 3121 |
| NEO | - |
| M1 | 11.600 |
| K1 | 6.500 |
| PC | - |
オスキュレーティング軌道要素
| 項目 | 値 |
|---|---|
| Epoch (epoch_cal, TDB) | 2020-08-06.0000000 |
| e | 0.24983241 |
| q (au) | 2.913890 |
| a (au) | 3.884319 |
| i (deg) | 9.182830 |
| Ω (om, deg) | 62.020609 |
| ω (w, deg) | 213.806901 |
| M (ma, deg) | 131.730867 |
等級
散乱 + 全体線形
$$ M_a = (10.993 + 2.725\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
モデル定数
| 項目 | 値 |
|---|---|
| H0 | 10.993 |
| n | 2.725 |
| gf | 0.805 |
| gb | -0.500 |
| k | 0.981 |
| δ90 | 1.000 |
| 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 |
|---|---|---|---|
| 2021-12-05 | 2024-04-07 | -8.8580 | +4.431 |
| 2024-04-07 | 2025-11-20 | +5.7345 | -3.224 |
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 | 21:45:30.18 | -20:51:27.9 | HIP 107427 | 42.03 |
| 2026-02-03 12:00 | 21:46:17.19 | -20:47:35.5 | HIP 107427 | 47.22 |
| 2026-02-04 00:00 | 21:47:04.17 | -20:43:42.8 | HIP 107748 | 38.68 |
| 2026-02-04 12:00 | 21:47:51.11 | -20:39:49.7 | HIP 107748 | 27.04 |
| 2026-02-05 00:00 | 21:48:38.01 | -20:35:56.3 | HIP 107748 | 15.40 |
| 2026-02-05 12:00 | 21:49:24.87 | -20:32:02.6 | HIP 107748 | 3.77 |
| 2026-02-06 00:00 | 21:50:11.69 | -20:28:08.6 | HIP 107748 | 7.89 |
| 2026-02-06 12:00 | 21:50:58.47 | -20:24:14.3 | HIP 107839 | 8.41 |
| 2026-02-07 00:00 | 21:51:45.21 | -20:20:19.6 | HIP 107845 | 14.56 |
| 2026-02-07 12:00 | 21:52:31.91 | -20:16:24.7 | HIP 107845 | 22.97 |
| 2026-02-08 00:00 | 21:53:18.57 | -20:12:29.4 | HIP 108072 | 13.71 |
| 2026-02-08 12:00 | 21:54:05.19 | -20:08:33.9 | HIP 108072 | 9.23 |
| 2026-02-09 00:00 | 21:54:51.77 | -20:04:38.1 | HIP 108072 | 15.90 |
| 2026-02-09 12:00 | 21:55:38.30 | -20:00:42.0 | HIP 108203 | 22.84 |
| 2026-02-10 00:00 | 21:56:24.80 | -19:56:45.6 | HIP 108203 | 24.13 |
| 2026-02-10 12:00 | 21:57:11.25 | -19:52:49.0 | HIP 108502 | 28.50 |
| 2026-02-11 00:00 | 21:57:57.65 | -19:48:52.1 | HIP 108502 | 17.53 |
| 2026-02-11 12:00 | 21:58:44.02 | -19:44:54.9 | HIP 108502 | 8.48 |
| 2026-02-12 00:00 | 21:59:30.34 | -19:40:57.5 | HIP 108502 | 10.29 |
| 2026-02-12 12:00 | 22:00:16.62 | -19:37:00.0 | HIP 108502 | 20.21 |
| 2026-02-13 00:00 | 22:01:02.85 | -19:33:02.0 | HIP 108708 | 14.54 |
| 2026-02-13 12:00 | 22:01:49.03 | -19:29:03.9 | HIP 108708 | 13.11 |
| 2026-02-14 00:00 | 22:02:35.18 | -19:25:05.6 | HIP 108708 | 20.02 |
| 2026-02-14 12:00 | 22:03:21.27 | -19:21:07.1 | HIP 108999 | 27.15 |
| 2026-02-15 00:00 | 22:04:07.32 | -19:17:08.4 | HIP 108999 | 16.48 |
| 2026-02-15 12:00 | 22:04:53.33 | -19:13:09.4 | HIP 108999 | 8.63 |
| 2026-02-16 00:00 | 22:05:39.28 | -19:09:10.3 | HIP 108999 | 12.03 |
| 2026-02-16 12:00 | 22:06:25.19 | -19:05:11.0 | HIP 108999 | 21.96 |
| 2026-02-17 00:00 | 22:07:11.06 | -19:01:11.5 | HIP 109077 | 28.81 |
| 2026-02-17 12:00 | 22:07:56.87 | -18:57:11.9 | HIP 109332 | 29.89 |
| 2026-02-18 00:00 | 22:08:42.63 | -18:53:12.1 | HIP 109332 | 22.36 |
| 2026-02-18 12:00 | 22:09:28.35 | -18:49:12.1 | HIP 109332 | 19.32 |
| 2026-02-19 00:00 | 22:10:14.01 | -18:45:12.0 | HIP 109332 | 22.64 |
| 2026-02-19 12:00 | 22:10:59.63 | -18:41:11.7 | HIP 109344 | 29.47 |
| 2026-02-20 00:00 | 22:11:45.20 | -18:37:11.3 | HIP 109634 | 37.33 |
| 2026-02-20 12:00 | 22:12:30.71 | -18:33:10.8 | HIP 109634 | 31.55 |
| 2026-02-21 00:00 | 22:13:16.17 | -18:29:10.1 | HIP 109634 | 29.37 |
| 2026-02-21 12:00 | 22:14:01.58 | -18:25:09.4 | HIP 109918 | 29.46 |
| 2026-02-22 00:00 | 22:14:46.94 | -18:21:08.5 | HIP 109918 | 18.49 |
| 2026-02-22 12:00 | 22:15:32.25 | -18:17:07.6 | HIP 109918 | 8.95 |
| 2026-02-23 00:00 | 22:16:17.50 | -18:13:06.5 | HIP 109918 | 9.03 |
| 2026-02-23 12:00 | 22:17:02.70 | -18:09:05.4 | HIP 110063 | 7.15 |
| 2026-02-24 00:00 | 22:17:47.85 | -18:05:04.2 | HIP 110063 | 5.88 |