217P/LINEAR
メタデータ
| 項目 | 値 |
|---|---|
| Designation | 217P/LINEAR |
| Type | P |
| Perihelion (tp_cal, UTC) | 2009-09-08T14:59:04.721280Z |
| Orbit solution date (soln_date, UTC) | 2026-07-07T05:52:40Z |
| Obs used | 3365 |
| NEO | Yes |
| M1 | 14.600 |
| 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) | 2013-01-19.0000000 |
| e | 0.68879936 |
| q (au) | 1.229136 |
| a (au) | 3.949658 |
| i (deg) | 12.861360 |
| Ω (om, deg) | 125.535703 |
| ω (w, deg) | 246.944396 |
| M (ma, deg) | 154.239661 |
等級
散乱 + 全体線形
$$ M_a = (10.106 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
モデル定数
| 項目 | 値 |
|---|---|
| H0 | 10.106 |
| n | 6.000 |
| gf | 0.801 |
| gb | -0.500 |
| k | 0.874 |
| 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 |
|---|---|---|---|
| 2024-05-01 | 2025-05-24 | -12.8918 | +1.338 |
| 2025-05-24 | 2025-11-02 | +5.5608 | -1.282 |
| 2025-11-02 | 2025-12-19 | +2.7111 | -0.241 |
| 2025-12-19 | 2026-02-15 | -32.1958 | +14.706 |
| 2026-02-15 | 2026-04-06 | +19.1139 | -10.797 |
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) |
|---|---|---|---|---|
| 2026-07-29 00:00 | 09:49:02.16 | +17:30:38.2 | HIP 48288 | 27.36 |
| 2026-07-29 12:00 | 09:49:32.73 | +17:28:24.1 | HIP 48288 | 22.77 |
| 2026-07-30 00:00 | 09:50:03.29 | +17:26:09.9 | HIP 48288 | 20.12 |
| 2026-07-30 12:00 | 09:50:33.83 | +17:23:55.5 | HIP 48372 | 16.25 |
| 2026-07-31 00:00 | 09:51:04.37 | +17:21:41.0 | HIP 48384 | 10.34 |
| 2026-07-31 12:00 | 09:51:34.88 | +17:19:26.4 | HIP 48384 | 3.46 |
| 2026-08-01 00:00 | 09:52:05.39 | +17:17:11.7 | HIP 48384 | 5.77 |
| 2026-08-01 12:00 | 09:52:35.88 | +17:14:56.8 | HIP 48384 | 13.06 |
| 2026-08-02 00:00 | 09:53:06.35 | +17:12:41.9 | HIP 48504 | 16.74 |
| 2026-08-02 12:00 | 09:53:36.81 | +17:10:26.8 | HIP 48560 | 9.51 |
| 2026-08-03 00:00 | 09:54:07.25 | +17:08:11.7 | HIP 48560 | 2.97 |
| 2026-08-03 12:00 | 09:54:37.68 | +17:05:56.4 | HIP 48560 | 6.56 |
| 2026-08-04 00:00 | 09:55:08.09 | +17:03:41.1 | HIP 48560 | 13.90 |
| 2026-08-04 12:00 | 09:55:38.48 | +17:01:25.6 | HIP 48560 | 21.42 |
| 2026-08-05 00:00 | 09:56:08.86 | +16:59:10.1 | HIP 48560 | 28.99 |
| 2026-08-05 12:00 | 09:56:39.22 | +16:56:54.5 | HIP 48823 | 32.13 |
| 2026-08-06 00:00 | 09:57:09.56 | +16:54:38.8 | HIP 48823 | 27.71 |
| 2026-08-06 12:00 | 09:57:39.88 | +16:52:23.1 | HIP 48823 | 24.88 |
| 2026-08-07 00:00 | 09:58:10.18 | +16:50:07.3 | HIP 48823 | 24.20 |
| 2026-08-07 12:00 | 09:58:40.47 | +16:47:51.4 | HIP 49007 | 18.04 |
| 2026-08-08 00:00 | 09:59:10.73 | +16:45:35.4 | HIP 49007 | 10.46 |
| 2026-08-08 12:00 | 09:59:40.98 | +16:43:19.4 | HIP 49007 | 2.91 |
| 2026-08-09 00:00 | 10:00:11.20 | +16:41:03.4 | HIP 49007 | 4.76 |
| 2026-08-09 12:00 | 10:00:41.40 | +16:38:47.3 | HIP 49007 | 12.32 |
| 2026-08-10 00:00 | 10:01:11.58 | +16:36:31.1 | HIP 49007 | 19.89 |
| 2026-08-10 12:00 | 10:01:41.74 | +16:34:15.0 | HIP 49007 | 27.46 |
| 2026-08-11 00:00 | 10:02:11.88 | +16:31:58.8 | HIP 49306 | 30.69 |
| 2026-08-11 12:00 | 10:02:41.99 | +16:29:42.5 | HIP 49306 | 23.76 |
| 2026-08-12 00:00 | 10:03:12.08 | +16:27:26.3 | HIP 49306 | 17.39 |
| 2026-08-12 12:00 | 10:03:42.14 | +16:25:10.0 | HIP 49306 | 12.44 |
| 2026-08-13 00:00 | 10:04:12.18 | +16:22:53.7 | HIP 49306 | 11.02 |
| 2026-08-13 12:00 | 10:04:42.19 | +16:20:37.4 | HIP 49422 | 11.16 |
| 2026-08-14 00:00 | 10:05:12.18 | +16:18:21.1 | HIP 49422 | 9.66 |
| 2026-08-14 12:00 | 10:05:42.14 | +16:16:04.9 | HIP 49422 | 13.25 |
| 2026-08-15 00:00 | 10:06:12.07 | +16:13:48.6 | HIP 49422 | 19.27 |
| 2026-08-15 12:00 | 10:06:41.98 | +16:11:32.4 | HIP 49627 | 15.41 |
| 2026-08-16 00:00 | 10:07:11.85 | +16:09:16.1 | HIP 49627 | 10.35 |
| 2026-08-16 12:00 | 10:07:41.70 | +16:07:00.0 | HIP 49627 | 9.49 |
| 2026-08-17 00:00 | 10:08:11.52 | +16:04:43.8 | HIP 49627 | 13.64 |
| 2026-08-17 12:00 | 10:08:41.31 | +16:02:27.7 | HIP 49627 | 19.86 |
| 2026-08-18 00:00 | 10:09:11.07 | +16:00:11.6 | HIP 49846 | 21.44 |
| 2026-08-18 12:00 | 10:09:40.79 | +15:57:55.5 | HIP 49846 | 14.84 |
| 2026-08-19 00:00 | 10:10:10.49 | +15:55:39.5 | HIP 49846 | 9.67 |