C/2023 P1 (Nishimura)
メタデータ
| 項目 | 値 |
|---|---|
| Designation | C/2023 P1 (Nishimura) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2023-09-17T15:23:38.446080Z |
| Orbit solution date (soln_date, UTC) | 2024-08-08T14:27:14Z |
| Obs used | 638 |
| NEO | - |
| M1 | 12.200 |
| K1 | 8.000 |
| PC | - |
| Discovery observation (MPC, UTC) | 2023-08-11T18:26:41.856000Z |
| Discovery magnitude (MPC) | 11.00 T |
| Discovery observatory (MPC) | 247 · Roving Observer |
オスキュレーティング軌道要素
| 項目 | 値 |
|---|---|
| Epoch (epoch_cal, TDB) | 2023-09-08.0000000 |
| e | 0.99610274 |
| q (au) | 0.225152 |
| a (au) | 57.771776 |
| i (deg) | 132.476418 |
| Ω (om, deg) | 66.834552 |
| ω (w, deg) | 116.297994 |
| M (ma, deg) | 359.978359 |
等級
散乱 + 全体線形
$$ M_a = (11.022 + 5.323\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
モデル定数
| 項目 | 値 |
|---|---|
| H0 | 11.022 |
| n | 5.323 |
| gf | 1.000 |
| gb | -0.978 |
| k | 0.946 |
| 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 |
|---|---|---|---|
| 2023-01-19 | 2023-09-16 | -0.0187 | +0.075 |
| 2023-09-18 | 2023-10-30 | -2.1846 | -1.278 |
| 2023-10-30 | 2023-11-23 | -5.0981 | -0.991 |
| 2023-11-23 | 2023-12-13 | -19.4714 | +2.497 |
| 2023-12-13 | 2023-12-31 | +61.6928 | -21.415 |
| 2023-12-31 | 2024-05-28 | -1.7731 | +0.482 |
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 | 08:33:52.83 | -34:47:17.8 | HIP 41980 | 10.25 |
| 2026-02-03 12:00 | 08:33:36.37 | -34:46:13.6 | HIP 41980 | 7.73 |
| 2026-02-04 00:00 | 08:33:19.95 | -34:45:07.9 | HIP 41980 | 6.27 |
| 2026-02-04 12:00 | 08:33:03.56 | -34:44:00.8 | HIP 41939 | 6.06 |
| 2026-02-05 00:00 | 08:32:47.22 | -34:42:52.3 | HIP 41939 | 5.36 |
| 2026-02-05 12:00 | 08:32:30.91 | -34:41:42.3 | HIP 41939 | 6.75 |
| 2026-02-06 00:00 | 08:32:14.65 | -34:40:30.9 | HIP 41939 | 9.35 |
| 2026-02-06 12:00 | 08:31:58.43 | -34:39:18.2 | HIP 41939 | 12.42 |
| 2026-02-07 00:00 | 08:31:42.26 | -34:38:04.0 | HIP 41939 | 15.69 |
| 2026-02-07 12:00 | 08:31:26.13 | -34:36:48.4 | HIP 41939 | 19.04 |
| 2026-02-08 00:00 | 08:31:10.06 | -34:35:31.4 | HIP 41939 | 22.46 |
| 2026-02-08 12:00 | 08:30:54.03 | -34:34:13.1 | HIP 41646 | 25.21 |
| 2026-02-09 00:00 | 08:30:38.06 | -34:32:53.4 | HIP 41646 | 22.05 |
| 2026-02-09 12:00 | 08:30:22.14 | -34:31:32.3 | HIP 41646 | 19.01 |
| 2026-02-10 00:00 | 08:30:06.28 | -34:30:09.8 | HIP 41646 | 16.17 |
| 2026-02-10 12:00 | 08:29:50.47 | -34:28:46.1 | HIP 41646 | 13.64 |
| 2026-02-11 00:00 | 08:29:34.72 | -34:27:21.0 | HIP 41646 | 11.64 |
| 2026-02-11 12:00 | 08:29:19.03 | -34:25:54.5 | HIP 41646 | 10.46 |
| 2026-02-12 00:00 | 08:29:03.41 | -34:24:26.8 | HIP 41646 | 10.40 |
| 2026-02-12 12:00 | 08:28:47.84 | -34:22:57.7 | HIP 41646 | 11.46 |
| 2026-02-13 00:00 | 08:28:32.34 | -34:21:27.4 | HIP 41646 | 13.38 |
| 2026-02-13 12:00 | 08:28:16.91 | -34:19:55.7 | HIP 41646 | 15.85 |
| 2026-02-14 00:00 | 08:28:01.54 | -34:18:22.8 | HIP 41646 | 18.65 |
| 2026-02-14 12:00 | 08:27:46.25 | -34:16:48.7 | HIP 41646 | 21.65 |
| 2026-02-15 00:00 | 08:27:31.02 | -34:15:13.3 | HIP 41410 | 22.38 |
| 2026-02-15 12:00 | 08:27:15.87 | -34:13:36.6 | HIP 41410 | 22.92 |
| 2026-02-16 00:00 | 08:27:00.79 | -34:11:58.7 | HIP 41278 | 23.54 |
| 2026-02-16 12:00 | 08:26:45.78 | -34:10:19.6 | HIP 41278 | 21.62 |
| 2026-02-17 00:00 | 08:26:30.85 | -34:08:39.3 | HIP 41278 | 20.17 |
| 2026-02-17 12:00 | 08:26:16.00 | -34:06:57.8 | HIP 41278 | 19.28 |
| 2026-02-18 00:00 | 08:26:01.23 | -34:05:15.1 | HIP 41278 | 19.02 |
| 2026-02-18 12:00 | 08:25:46.54 | -34:03:31.3 | HIP 41278 | 19.43 |
| 2026-02-19 00:00 | 08:25:31.93 | -34:01:46.3 | HIP 41278 | 20.46 |
| 2026-02-19 12:00 | 08:25:17.40 | -34:00:00.1 | HIP 41278 | 22.01 |
| 2026-02-20 00:00 | 08:25:02.96 | -33:58:12.9 | HIP 41278 | 24.00 |
| 2026-02-20 12:00 | 08:24:48.60 | -33:56:24.5 | HIP 41324 | 26.25 |
| 2026-02-21 00:00 | 08:24:34.33 | -33:54:35.0 | HIP 41041 | 25.21 |
| 2026-02-21 12:00 | 08:24:20.15 | -33:52:44.5 | HIP 41041 | 22.42 |
| 2026-02-22 00:00 | 08:24:06.06 | -33:50:52.8 | HIP 41041 | 19.86 |
| 2026-02-22 12:00 | 08:23:52.06 | -33:49:00.1 | HIP 41041 | 17.64 |
| 2026-02-23 00:00 | 08:23:38.16 | -33:47:06.4 | HIP 41041 | 15.89 |
| 2026-02-23 12:00 | 08:23:24.34 | -33:45:11.6 | HIP 41041 | 14.78 |
| 2026-02-24 00:00 | 08:23:10.62 | -33:43:15.9 | HIP 41041 | 14.45 |