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
$$ M_a = (10.942 + 5.266\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
モデル定数
| 項目 | 値 |
|---|---|
| H0 | 10.942 |
| n | 5.266 |
| gf | 0.997 |
| gb | -0.921 |
| k | 0.944 |
| δ90 | 9.998 |
| 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 | +0.1403 | +0.148 |
| 2023-09-18 | 2024-05-28 | -0.5521 | -1.485 |
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) |
|---|---|---|---|---|
| 2026-09-20 00:00 | 08:48:33.39 | -27:44:52.8 | HIP 43149 | 16.27 |
| 2026-09-20 12:00 | 08:48:39.76 | -27:46:28.1 | HIP 43149 | 17.65 |
| 2026-09-21 00:00 | 08:48:46.06 | -27:48:03.8 | HIP 43149 | 19.15 |
| 2026-09-21 12:00 | 08:48:52.29 | -27:49:40.0 | HIP 43149 | 20.74 |
| 2026-09-22 00:00 | 08:48:58.46 | -27:51:16.6 | HIP 43149 | 22.41 |
| 2026-09-22 12:00 | 08:49:04.56 | -27:52:53.6 | HIP 43409 | 21.91 |
| 2026-09-23 00:00 | 08:49:10.59 | -27:54:30.9 | HIP 43409 | 21.59 |
| 2026-09-23 12:00 | 08:49:16.56 | -27:56:08.7 | HIP 43334 | 20.04 |
| 2026-09-24 00:00 | 08:49:22.46 | -27:57:46.8 | HIP 43334 | 18.12 |
| 2026-09-24 12:00 | 08:49:28.29 | -27:59:25.4 | HIP 43334 | 16.23 |
| 2026-09-25 00:00 | 08:49:34.05 | -28:01:04.3 | HIP 43334 | 14.40 |
| 2026-09-25 12:00 | 08:49:39.74 | -28:02:43.5 | HIP 43334 | 12.64 |
| 2026-09-26 00:00 | 08:49:45.36 | -28:04:23.2 | HIP 43334 | 10.99 |
| 2026-09-26 12:00 | 08:49:50.91 | -28:06:03.2 | HIP 43334 | 9.49 |
| 2026-09-27 00:00 | 08:49:56.39 | -28:07:43.5 | HIP 43334 | 8.23 |
| 2026-09-27 12:00 | 08:50:01.80 | -28:09:24.2 | HIP 43334 | 7.33 |
| 2026-09-28 00:00 | 08:50:07.14 | -28:11:05.3 | HIP 43334 | 6.92 |
| 2026-09-28 12:00 | 08:50:12.40 | -28:12:46.6 | HIP 43334 | 7.09 |
| 2026-09-29 00:00 | 08:50:17.59 | -28:14:28.4 | HIP 43334 | 7.80 |
| 2026-09-29 12:00 | 08:50:22.71 | -28:16:10.4 | HIP 43404 | 7.33 |
| 2026-09-30 00:00 | 08:50:27.76 | -28:17:52.8 | HIP 43404 | 5.53 |
| 2026-09-30 12:00 | 08:50:32.73 | -28:19:35.4 | HIP 43404 | 3.94 |
| 2026-10-01 00:00 | 08:50:37.62 | -28:21:18.4 | HIP 43404 | 2.94 |
| 2026-10-01 12:00 | 08:50:42.44 | -28:23:01.7 | HIP 43404 | 3.14 |
| 2026-10-02 00:00 | 08:50:47.19 | -28:24:45.3 | HIP 43404 | 4.37 |
| 2026-10-02 12:00 | 08:50:51.86 | -28:26:29.2 | HIP 43404 | 6.03 |
| 2026-10-03 00:00 | 08:50:56.45 | -28:28:13.4 | HIP 43404 | 7.85 |
| 2026-10-03 12:00 | 08:51:00.97 | -28:29:57.9 | HIP 43404 | 9.73 |
| 2026-10-04 00:00 | 08:51:05.41 | -28:31:42.6 | HIP 43394 | 10.99 |
| 2026-10-04 12:00 | 08:51:09.77 | -28:33:27.6 | HIP 43394 | 11.16 |
| 2026-10-05 00:00 | 08:51:14.05 | -28:35:12.9 | HIP 43394 | 11.65 |
| 2026-10-05 12:00 | 08:51:18.25 | -28:36:58.4 | HIP 43394 | 12.42 |
| 2026-10-06 00:00 | 08:51:22.37 | -28:38:44.2 | HIP 43394 | 13.43 |
| 2026-10-06 12:00 | 08:51:26.41 | -28:40:30.3 | HIP 43394 | 14.62 |
| 2026-10-07 00:00 | 08:51:30.38 | -28:42:16.5 | HIP 43394 | 15.95 |
| 2026-10-07 12:00 | 08:51:34.26 | -28:44:03.0 | HIP 43394 | 17.39 |
| 2026-10-08 00:00 | 08:51:38.05 | -28:45:49.7 | HIP 43389 | 18.13 |
| 2026-10-08 12:00 | 08:51:41.77 | -28:47:36.7 | HIP 43389 | 18.43 |
| 2026-10-09 00:00 | 08:51:45.40 | -28:49:23.8 | HIP 43389 | 18.91 |
| 2026-10-09 12:00 | 08:51:48.95 | -28:51:11.2 | HIP 43389 | 19.55 |
| 2026-10-10 00:00 | 08:51:52.42 | -28:52:58.7 | HIP 43389 | 20.34 |
| 2026-10-10 12:00 | 08:51:55.80 | -28:54:46.4 | HIP 43389 | 21.27 |
| 2026-10-11 00:00 | 08:51:59.10 | -28:56:34.3 | HIP 43389 | 22.30 |