C/2020 F3 (NEOWISE)
メタデータ
| 項目 | 値 |
|---|---|
| Designation | C/2020 F3 (NEOWISE) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2020-07-03T16:17:36.787200Z |
| Orbit solution date (soln_date, UTC) | 2024-07-30T14:57:24Z |
| Obs used | 1315 |
| NEO | - |
| M1 | 12.100 |
| K1 | 12.250 |
| PC | - |
オスキュレーティング軌道要素
| 項目 | 値 |
|---|---|
| Epoch (epoch_cal, TDB) | 2020-07-06.0000000 |
| e | 0.99917803 |
| q (au) | 0.294651 |
| a (au) | 358.467957 |
| i (deg) | 128.937503 |
| Ω (om, deg) | 61.010428 |
| ω (w, deg) | 37.278658 |
| M (ma, deg) | 0.000337 |
等級
散乱 + 全体線形
$$ M_a = (8.535 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
モデル定数
| 項目 | 値 |
|---|---|
| H0 | 8.535 |
| n | 6.000 |
| 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 |
|---|---|---|---|
| 2020-03-27 | 2020-04-22 | +19.1066 | -3.757 |
| 2020-04-22 | 2020-05-07 | +13.0268 | -2.831 |
| 2020-05-07 | 2020-07-03 | +0.2884 | -1.478 |
| 2020-07-04 | 2020-07-17 | +2.2790 | +1.205 |
| 2020-07-17 | 2023-04-14 | -6.6559 | -0.824 |
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) |
|---|---|---|---|---|
| 2026-05-12 00:00 | 14:28:32.21 | -34:12:10.6 | HIP 70883 | 37.12 |
| 2026-05-12 12:00 | 14:28:24.13 | -34:11:35.3 | HIP 70883 | 38.35 |
| 2026-05-13 00:00 | 14:28:16.08 | -34:10:59.7 | HIP 70883 | 39.63 |
| 2026-05-13 12:00 | 14:28:08.04 | -34:10:23.8 | HIP 70555 | 40.41 |
| 2026-05-14 00:00 | 14:28:00.02 | -34:09:47.7 | HIP 70555 | 39.79 |
| 2026-05-14 12:00 | 14:27:52.02 | -34:09:11.3 | HIP 70555 | 39.25 |
| 2026-05-15 00:00 | 14:27:44.05 | -34:08:34.7 | HIP 70555 | 38.78 |
| 2026-05-15 12:00 | 14:27:36.09 | -34:07:57.9 | HIP 70555 | 38.39 |
| 2026-05-16 00:00 | 14:27:28.16 | -34:07:20.8 | HIP 70555 | 38.09 |
| 2026-05-16 12:00 | 14:27:20.26 | -34:06:43.5 | HIP 70555 | 37.87 |
| 2026-05-17 00:00 | 14:27:12.37 | -34:06:06.0 | HIP 70555 | 37.74 |
| 2026-05-17 12:00 | 14:27:04.52 | -34:05:28.2 | HIP 70407 | 36.48 |
| 2026-05-18 00:00 | 14:26:56.68 | -34:04:50.3 | HIP 70407 | 34.75 |
| 2026-05-18 12:00 | 14:26:48.88 | -34:04:12.1 | HIP 70407 | 33.03 |
| 2026-05-19 00:00 | 14:26:41.10 | -34:03:33.7 | HIP 70407 | 31.31 |
| 2026-05-19 12:00 | 14:26:33.35 | -34:02:55.1 | HIP 70407 | 29.59 |
| 2026-05-20 00:00 | 14:26:25.63 | -34:02:16.4 | HIP 70407 | 27.88 |
| 2026-05-20 12:00 | 14:26:17.93 | -34:01:37.4 | HIP 70407 | 26.18 |
| 2026-05-21 00:00 | 14:26:10.27 | -34:00:58.2 | HIP 70407 | 24.49 |
| 2026-05-21 12:00 | 14:26:02.64 | -34:00:18.8 | HIP 70407 | 22.81 |
| 2026-05-22 00:00 | 14:25:55.04 | -33:59:39.3 | HIP 70407 | 21.13 |
| 2026-05-22 12:00 | 14:25:47.46 | -33:58:59.6 | HIP 70407 | 19.47 |
| 2026-05-23 00:00 | 14:25:39.93 | -33:58:19.7 | HIP 70407 | 17.83 |
| 2026-05-23 12:00 | 14:25:32.42 | -33:57:39.6 | HIP 70407 | 16.19 |
| 2026-05-24 00:00 | 14:25:24.94 | -33:56:59.4 | HIP 70407 | 14.58 |
| 2026-05-24 12:00 | 14:25:17.50 | -33:56:19.0 | HIP 70407 | 13.00 |
| 2026-05-25 00:00 | 14:25:10.10 | -33:55:38.4 | HIP 70407 | 11.45 |
| 2026-05-25 12:00 | 14:25:02.73 | -33:54:57.7 | HIP 70407 | 9.95 |
| 2026-05-26 00:00 | 14:24:55.39 | -33:54:16.9 | HIP 70407 | 8.51 |
| 2026-05-26 12:00 | 14:24:48.09 | -33:53:35.8 | HIP 70407 | 7.19 |
| 2026-05-27 00:00 | 14:24:40.83 | -33:52:54.7 | HIP 70407 | 6.05 |
| 2026-05-27 12:00 | 14:24:33.60 | -33:52:13.4 | HIP 70407 | 5.20 |
| 2026-05-28 00:00 | 14:24:26.41 | -33:51:32.0 | HIP 70407 | 4.79 |
| 2026-05-28 12:00 | 14:24:19.26 | -33:50:50.4 | HIP 70407 | 4.93 |
| 2026-05-29 00:00 | 14:24:12.14 | -33:50:08.7 | HIP 70407 | 5.58 |
| 2026-05-29 12:00 | 14:24:05.07 | -33:49:26.9 | HIP 70407 | 6.57 |
| 2026-05-30 00:00 | 14:23:58.03 | -33:48:45.0 | HIP 70407 | 7.78 |
| 2026-05-30 12:00 | 14:23:51.03 | -33:48:03.0 | HIP 70407 | 9.11 |
| 2026-05-31 00:00 | 14:23:44.08 | -33:47:20.8 | HIP 70407 | 10.52 |
| 2026-05-31 12:00 | 14:23:37.16 | -33:46:38.5 | HIP 70407 | 11.97 |
| 2026-06-01 00:00 | 14:23:30.28 | -33:45:56.2 | HIP 70407 | 13.46 |
| 2026-06-01 12:00 | 14:23:23.45 | -33:45:13.7 | HIP 70407 | 14.96 |
| 2026-06-02 00:00 | 14:23:16.66 | -33:44:31.2 | HIP 70407 | 16.47 |