103P/Hartley 2
メタデータ
| 項目 | 値 |
|---|---|
| Designation | 103P/Hartley 2 |
| Type | P |
| Perihelion (tp_cal, UTC) | 2017-04-20T10:59:29.739840Z |
| Orbit solution date (soln_date, UTC) | 2025-05-01T10:45:38Z |
| Obs used | 8768 |
| NEO | Yes |
| M1 | 16.000 |
| K1 | 4.500 |
| PC | - |
オスキュレーティング軌道要素
| 項目 | 値 |
|---|---|
| Epoch (epoch_cal, TDB) | 2015-05-10.0000000 |
| e | 0.69359786 |
| q (au) | 1.064947 |
| a (au) | 3.475652 |
| i (deg) | 13.599468 |
| Ω (om, deg) | 219.742174 |
| ω (w, deg) | 181.321844 |
| M (ma, deg) | 251.782173 |
等級
散乱 + 全体線形
$$ M_a = (15.100 + 3.424\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
モデル定数
| 項目 | 値 |
|---|---|
| H0 | 15.100 |
| n | 3.424 |
| gf | 1.000 |
| gb | -0.827 |
| k | 0.954 |
| 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 |
|---|---|---|---|
| 2023-04-17 | 2024-02-18 | +8.1437 | -2.155 |
| 2024-02-18 | 2025-04-28 | -2.9095 | +0.580 |
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) |
|---|---|---|---|---|
| 2026-03-26 00:00 | 14:07:35.66 | -15:51:04.4 | HIP 68970 | 21.02 |
| 2026-03-26 12:00 | 14:07:20.38 | -15:49:32.4 | HIP 68970 | 21.94 |
| 2026-03-27 00:00 | 14:07:04.99 | -15:47:59.6 | HIP 68970 | 23.53 |
| 2026-03-27 12:00 | 14:06:49.47 | -15:46:25.9 | HIP 68970 | 25.67 |
| 2026-03-28 00:00 | 14:06:33.85 | -15:44:51.4 | HIP 68900 | 27.99 |
| 2026-03-28 12:00 | 14:06:18.12 | -15:43:16.1 | HIP 68900 | 29.53 |
| 2026-03-29 00:00 | 14:06:02.27 | -15:41:40.0 | HIP 68729 | 30.31 |
| 2026-03-29 12:00 | 14:05:46.32 | -15:40:03.0 | HIP 68729 | 26.15 |
| 2026-03-30 00:00 | 14:05:30.27 | -15:38:25.2 | HIP 68729 | 21.96 |
| 2026-03-30 12:00 | 14:05:14.12 | -15:36:46.7 | HIP 68729 | 17.74 |
| 2026-03-31 00:00 | 14:04:57.87 | -15:35:07.4 | HIP 68729 | 13.50 |
| 2026-03-31 12:00 | 14:04:41.52 | -15:33:27.3 | HIP 68729 | 9.23 |
| 2026-04-01 00:00 | 14:04:25.07 | -15:31:46.4 | HIP 68729 | 4.95 |
| 2026-04-01 12:00 | 14:04:08.53 | -15:30:04.8 | HIP 68729 | 0.94 |
| 2026-04-02 00:00 | 14:03:51.91 | -15:28:22.4 | HIP 68729 | 3.86 |
| 2026-04-02 12:00 | 14:03:35.19 | -15:26:39.4 | HIP 68729 | 8.20 |
| 2026-04-03 00:00 | 14:03:18.39 | -15:24:55.6 | HIP 68729 | 12.59 |
| 2026-04-03 12:00 | 14:03:01.50 | -15:23:11.0 | HIP 68729 | 17.01 |
| 2026-04-04 00:00 | 14:02:44.54 | -15:21:25.8 | HIP 68729 | 21.46 |
| 2026-04-04 12:00 | 14:02:27.49 | -15:19:39.9 | HIP 68729 | 25.93 |
| 2026-04-05 00:00 | 14:02:10.37 | -15:17:53.3 | HIP 68480 | 29.97 |
| 2026-04-05 12:00 | 14:01:53.17 | -15:16:06.1 | HIP 68480 | 26.58 |
| 2026-04-06 00:00 | 14:01:35.91 | -15:14:18.2 | HIP 68480 | 23.55 |
| 2026-04-06 12:00 | 14:01:18.57 | -15:12:29.6 | HIP 68425 | 19.59 |
| 2026-04-07 00:00 | 14:01:01.17 | -15:10:40.5 | HIP 68425 | 15.71 |
| 2026-04-07 12:00 | 14:00:43.70 | -15:08:50.7 | HIP 68425 | 12.30 |
| 2026-04-08 00:00 | 14:00:26.17 | -15:07:00.3 | HIP 68425 | 9.89 |
| 2026-04-08 12:00 | 14:00:08.58 | -15:05:09.3 | HIP 68425 | 9.33 |
| 2026-04-09 00:00 | 13:59:50.93 | -15:03:17.7 | HIP 68425 | 10.92 |
| 2026-04-09 12:00 | 13:59:33.23 | -15:01:25.5 | HIP 68425 | 13.96 |
| 2026-04-10 00:00 | 13:59:15.48 | -14:59:32.8 | HIP 68425 | 17.74 |
| 2026-04-10 12:00 | 13:58:57.68 | -14:57:39.6 | HIP 68425 | 21.88 |
| 2026-04-11 00:00 | 13:58:39.83 | -14:55:45.8 | HIP 68425 | 26.22 |
| 2026-04-11 12:00 | 13:58:21.94 | -14:53:51.5 | HIP 68425 | 30.68 |
| 2026-04-12 00:00 | 13:58:04.01 | -14:51:56.7 | HIP 68291 | 30.17 |
| 2026-04-12 12:00 | 13:57:46.03 | -14:50:01.5 | HIP 68025 | 28.59 |
| 2026-04-13 00:00 | 13:57:28.03 | -14:48:05.7 | HIP 68025 | 24.14 |
| 2026-04-13 12:00 | 13:57:09.99 | -14:46:09.5 | HIP 68025 | 19.83 |
| 2026-04-14 00:00 | 13:56:51.91 | -14:44:12.9 | HIP 68025 | 15.78 |
| 2026-04-14 12:00 | 13:56:33.81 | -14:42:15.8 | HIP 68025 | 12.27 |
| 2026-04-15 00:00 | 13:56:15.69 | -14:40:18.3 | HIP 68025 | 9.89 |
| 2026-04-15 12:00 | 13:55:57.54 | -14:38:20.5 | HIP 68025 | 9.56 |
| 2026-04-16 00:00 | 13:55:39.38 | -14:36:22.2 | HIP 68025 | 11.45 |