378P/McNaught
メタデータ
| 項目 | 値 |
|---|---|
| Designation | 378P/McNaught |
| Type | P |
| Perihelion (tp_cal, UTC) | 2020-10-21T12:01:27.851520Z |
| Orbit solution date (soln_date, UTC) | 2026-01-13T08:12:54Z |
| Obs used | 828 |
| NEO | - |
| M1 | 12.200 |
| K1 | 4.500 |
| PC | - |
| Discovery observation (MPC, UTC) | 2019-03-10T03:16:12.864000Z |
| Discovery magnitude (MPC) | 21.90 G |
| Discovery observatory (MPC) | J04 · ESA Optical Ground Station, Tenerife |
オスキュレーティング軌道要素
| 項目 | 値 |
|---|---|
| Epoch (epoch_cal, TDB) | 2020-05-16.0000000 |
| e | 0.46883776 |
| q (au) | 3.380503 |
| a (au) | 6.364351 |
| i (deg) | 19.108649 |
| Ω (om, deg) | 94.516291 |
| ω (w, deg) | 194.158503 |
| M (ma, deg) | 350.270176 |
等級
散乱 + 全体線形
$$ M_a = (15.990 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
モデル定数
| 項目 | 値 |
|---|---|
| H0 | 15.990 |
| n | 2.000 |
| gf | 0.993 |
| gb | -0.828 |
| k | 0.800 |
| 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 |
|---|---|---|---|
| 2019-02-17 | 2020-04-05 | +16.4000 | -8.371 |
| 2021-04-03 | 2021-09-29 | -16.9920 | +11.467 |
| 2021-09-29 | 2022-12-16 | -7.8118 | +5.383 |
| 2022-12-16 | 2023-12-10 | +7.1269 | -6.004 |
| 2023-12-10 | 2026-01-12 | +4.0390 | -3.670 |
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 | 05:06:20.33 | +19:28:32.3 | HIP 23695 | 22.88 |
| 2026-03-26 12:00 | 05:06:27.88 | +19:29:10.2 | HIP 23695 | 23.29 |
| 2026-03-27 00:00 | 05:06:35.54 | +19:29:48.1 | HIP 23695 | 23.86 |
| 2026-03-27 12:00 | 05:06:43.31 | +19:30:26.0 | HIP 23695 | 24.58 |
| 2026-03-28 00:00 | 05:06:51.17 | +19:31:04.0 | HIP 23695 | 25.44 |
| 2026-03-28 12:00 | 05:06:59.13 | +19:31:42.0 | HIP 23695 | 26.43 |
| 2026-03-29 00:00 | 05:07:07.19 | +19:32:19.9 | HIP 23695 | 27.56 |
| 2026-03-29 12:00 | 05:07:15.35 | +19:32:57.9 | HIP 23695 | 28.79 |
| 2026-03-30 00:00 | 05:07:23.61 | +19:33:36.0 | HIP 23949 | 27.23 |
| 2026-03-30 12:00 | 05:07:31.97 | +19:34:14.0 | HIP 23949 | 25.34 |
| 2026-03-31 00:00 | 05:07:40.42 | +19:34:52.0 | HIP 23949 | 23.48 |
| 2026-03-31 12:00 | 05:07:48.97 | +19:35:30.1 | HIP 23949 | 21.64 |
| 2026-04-01 00:00 | 05:07:57.62 | +19:36:08.1 | HIP 23949 | 19.83 |
| 2026-04-01 12:00 | 05:08:06.36 | +19:36:46.2 | HIP 23949 | 18.09 |
| 2026-04-02 00:00 | 05:08:15.19 | +19:37:24.2 | HIP 23949 | 16.43 |
| 2026-04-02 12:00 | 05:08:24.12 | +19:38:02.3 | HIP 23949 | 14.90 |
| 2026-04-03 00:00 | 05:08:33.15 | +19:38:40.3 | HIP 23949 | 13.55 |
| 2026-04-03 12:00 | 05:08:42.26 | +19:39:18.4 | HIP 23949 | 12.44 |
| 2026-04-04 00:00 | 05:08:51.47 | +19:39:56.4 | HIP 23949 | 11.66 |
| 2026-04-04 12:00 | 05:09:00.77 | +19:40:34.5 | HIP 23949 | 11.28 |
| 2026-04-05 00:00 | 05:09:10.16 | +19:41:12.5 | HIP 23949 | 11.38 |
| 2026-04-05 12:00 | 05:09:19.65 | +19:41:50.5 | HIP 23949 | 11.93 |
| 2026-04-06 00:00 | 05:09:29.22 | +19:42:28.5 | HIP 23949 | 12.90 |
| 2026-04-06 12:00 | 05:09:38.88 | +19:43:06.5 | HIP 23949 | 14.21 |
| 2026-04-07 00:00 | 05:09:48.63 | +19:43:44.5 | HIP 23949 | 15.78 |
| 2026-04-07 12:00 | 05:09:58.47 | +19:44:22.5 | HIP 23949 | 17.56 |
| 2026-04-08 00:00 | 05:10:08.40 | +19:45:00.4 | HIP 23949 | 19.49 |
| 2026-04-08 12:00 | 05:10:18.41 | +19:45:38.4 | HIP 23949 | 21.53 |
| 2026-04-09 00:00 | 05:10:28.51 | +19:46:16.3 | HIP 23949 | 23.67 |
| 2026-04-09 12:00 | 05:10:38.70 | +19:46:54.2 | HIP 23949 | 25.89 |
| 2026-04-10 00:00 | 05:10:48.97 | +19:47:32.0 | HIP 24284 | 27.68 |
| 2026-04-10 12:00 | 05:10:59.33 | +19:48:09.8 | HIP 24284 | 25.55 |
| 2026-04-11 00:00 | 05:11:09.77 | +19:48:47.6 | HIP 24284 | 23.46 |
| 2026-04-11 12:00 | 05:11:20.30 | +19:49:25.4 | HIP 24284 | 21.46 |
| 2026-04-12 00:00 | 05:11:30.90 | +19:50:03.1 | HIP 24284 | 19.58 |
| 2026-04-12 12:00 | 05:11:41.60 | +19:50:40.8 | HIP 24284 | 17.85 |
| 2026-04-13 00:00 | 05:11:52.37 | +19:51:18.5 | HIP 24284 | 16.33 |
| 2026-04-13 12:00 | 05:12:03.22 | +19:51:56.1 | HIP 24301 | 14.51 |
| 2026-04-14 00:00 | 05:12:14.16 | +19:52:33.7 | HIP 24301 | 12.95 |
| 2026-04-14 12:00 | 05:12:25.18 | +19:53:11.2 | HIP 24301 | 11.78 |
| 2026-04-15 00:00 | 05:12:36.27 | +19:53:48.7 | HIP 24301 | 11.12 |
| 2026-04-15 12:00 | 05:12:47.45 | +19:54:26.2 | HIP 24301 | 11.09 |
| 2026-04-16 00:00 | 05:12:58.70 | +19:55:03.6 | HIP 24301 | 11.70 |