C/1991 X2 (Mueller)
メタデータ
| 項目 | 値 |
|---|---|
| Designation | C/1991 X2 (Mueller) |
| Type | C |
| Perihelion (tp_cal, UTC) | 1992-03-21T04:48:32.227200Z |
| Orbit solution date (soln_date, UTC) | 2021-04-15T23:29:41Z |
| Obs used | 149 |
| NEO | - |
| M1 | 12.100 |
| K1 | 16.750 |
| PC | - |
オスキュレーティング軌道要素
| 項目 | 値 |
|---|---|
| Epoch (epoch_cal, TDB) | 1992-01-30.0000000 |
| e | 1.00020139 |
| q (au) | 0.198797 |
| a (au) | -987.134248 |
| i (deg) | 95.574370 |
| Ω (om, deg) | 288.783115 |
| ω (w, deg) | 306.985362 |
| M (ma, deg) | -0.001627 |
等級
散乱 + 全体線形
$$ M_a = (10.627 + 5.215\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
モデル定数
| 項目 | 値 |
|---|---|
| H0 | 10.627 |
| n | 5.215 |
| 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 |
|---|---|---|---|
| 1991-12-13 | 1992-03-09 | -0.0653 | +0.214 |
| 1992-03-21 | 1992-04-13 | +12.3150 | +4.801 |
log10 r = log10(太陽距離/AU)、Δ = 地球距離(AU)
天体暦
| Date/Time (UTC) | RA (J2000) | Dec (J2000) | Nearest HIP | Dist from HIP (arcmin) |
|---|---|---|---|---|
| 2026-02-03 00:00 | 11:01:14.58 | +76:06:25.3 | HIP 53979 | 13.16 |
| 2026-02-03 12:00 | 11:01:07.69 | +76:06:43.3 | HIP 53979 | 13.60 |
| 2026-02-04 00:00 | 11:01:00.76 | +76:07:01.0 | HIP 53979 | 14.03 |
| 2026-02-04 12:00 | 11:00:53.80 | +76:07:18.5 | HIP 53979 | 14.47 |
| 2026-02-05 00:00 | 11:00:46.79 | +76:07:35.8 | HIP 53979 | 14.91 |
| 2026-02-05 12:00 | 11:00:39.75 | +76:07:52.9 | HIP 53979 | 15.35 |
| 2026-02-06 00:00 | 11:00:32.68 | +76:08:09.7 | HIP 53979 | 15.80 |
| 2026-02-06 12:00 | 11:00:25.57 | +76:08:26.3 | HIP 53979 | 16.24 |
| 2026-02-07 00:00 | 11:00:18.42 | +76:08:42.7 | HIP 53979 | 16.69 |
| 2026-02-07 12:00 | 11:00:11.24 | +76:08:58.9 | HIP 53979 | 17.14 |
| 2026-02-08 00:00 | 11:00:04.03 | +76:09:14.9 | HIP 53979 | 17.59 |
| 2026-02-08 12:00 | 10:59:56.78 | +76:09:30.6 | HIP 53979 | 18.04 |
| 2026-02-09 00:00 | 10:59:49.50 | +76:09:46.1 | HIP 53979 | 18.49 |
| 2026-02-09 12:00 | 10:59:42.19 | +76:10:01.4 | HIP 53979 | 18.94 |
| 2026-02-10 00:00 | 10:59:34.85 | +76:10:16.4 | HIP 53979 | 19.39 |
| 2026-02-10 12:00 | 10:59:27.48 | +76:10:31.2 | HIP 53327 | 19.16 |
| 2026-02-11 00:00 | 10:59:20.08 | +76:10:45.8 | HIP 53327 | 18.83 |
| 2026-02-11 12:00 | 10:59:12.65 | +76:11:00.1 | HIP 53327 | 18.50 |
| 2026-02-12 00:00 | 10:59:05.19 | +76:11:14.2 | HIP 53327 | 18.18 |
| 2026-02-12 12:00 | 10:58:57.70 | +76:11:28.1 | HIP 53327 | 17.86 |
| 2026-02-13 00:00 | 10:58:50.19 | +76:11:41.7 | HIP 53327 | 17.55 |
| 2026-02-13 12:00 | 10:58:42.65 | +76:11:55.1 | HIP 53327 | 17.25 |
| 2026-02-14 00:00 | 10:58:35.08 | +76:12:08.2 | HIP 53327 | 16.95 |
| 2026-02-14 12:00 | 10:58:27.49 | +76:12:21.1 | HIP 53327 | 16.66 |
| 2026-02-15 00:00 | 10:58:19.87 | +76:12:33.8 | HIP 53327 | 16.38 |
| 2026-02-15 12:00 | 10:58:12.23 | +76:12:46.2 | HIP 53327 | 16.10 |
| 2026-02-16 00:00 | 10:58:04.57 | +76:12:58.3 | HIP 53327 | 15.83 |
| 2026-02-16 12:00 | 10:57:56.89 | +76:13:10.3 | HIP 53327 | 15.58 |
| 2026-02-17 00:00 | 10:57:49.18 | +76:13:21.9 | HIP 53327 | 15.32 |
| 2026-02-17 12:00 | 10:57:41.45 | +76:13:33.3 | HIP 53327 | 15.08 |
| 2026-02-18 00:00 | 10:57:33.71 | +76:13:44.5 | HIP 53327 | 14.85 |
| 2026-02-18 12:00 | 10:57:25.94 | +76:13:55.4 | HIP 53327 | 14.63 |
| 2026-02-19 00:00 | 10:57:18.16 | +76:14:06.1 | HIP 53327 | 14.41 |
| 2026-02-19 12:00 | 10:57:10.35 | +76:14:16.5 | HIP 53327 | 14.21 |
| 2026-02-20 00:00 | 10:57:02.53 | +76:14:26.6 | HIP 53327 | 14.02 |
| 2026-02-20 12:00 | 10:56:54.70 | +76:14:36.5 | HIP 53327 | 13.84 |
| 2026-02-21 00:00 | 10:56:46.85 | +76:14:46.1 | HIP 53327 | 13.68 |
| 2026-02-21 12:00 | 10:56:38.98 | +76:14:55.5 | HIP 53327 | 13.52 |
| 2026-02-22 00:00 | 10:56:31.10 | +76:15:04.6 | HIP 53327 | 13.38 |
| 2026-02-22 12:00 | 10:56:23.21 | +76:15:13.5 | HIP 53327 | 13.25 |
| 2026-02-23 00:00 | 10:56:15.31 | +76:15:22.1 | HIP 53327 | 13.13 |
| 2026-02-23 12:00 | 10:56:07.39 | +76:15:30.5 | HIP 53327 | 13.03 |
| 2026-02-24 00:00 | 10:55:59.46 | +76:15:38.6 | HIP 53327 | 12.94 |