C/2025 J1 (Borisov)
メタデータ
| 項目 | 値 |
|---|---|
| Designation | C/2025 J1 (Borisov) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2026-06-11T19:27:02.733120Z |
| Orbit solution date (soln_date, UTC) | 2026-07-06T12:12:24Z |
| Obs used | 908 |
| NEO | - |
| M1 | 8.400 |
| K1 | 10.500 |
| PC | 0.030 |
| Discovery observation (MPC, UTC) | 2025-05-02T23:26:46.752000Z |
| Discovery magnitude (MPC) | 19.30 G |
| Discovery observatory (MPC) | L51 · MARGO, Nauchnyi |
オスキュレーティング軌道要素
| 項目 | 値 |
|---|---|
| Epoch (epoch_cal, TDB) | 2025-11-23.0000000 |
| e | 0.99713314 |
| q (au) | 3.580304 |
| a (au) | 1248.859286 |
| i (deg) | 95.444631 |
| Ω (om, deg) | 273.976296 |
| ω (w, deg) | 166.624134 |
| M (ma, deg) | 359.995515 |
等級
散乱 + 全体線形
$$ M_a = (9.260 + 5.836\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
モデル定数
| 項目 | 値 |
|---|---|
| H0 | 9.260 |
| n | 5.836 |
| gf | 1.000 |
| gb | -0.832 |
| 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 |
|---|---|---|---|
| 2025-04-29 | 2025-10-22 | +3.9386 | -2.677 |
| 2025-10-22 | 2026-05-05 | -12.9890 | +7.599 |
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) |
|---|---|---|---|---|
| 2026-07-29 00:00 | 06:49:10.35 | +25:55:48.6 | HIP 32663 | 22.53 |
| 2026-07-29 12:00 | 06:49:32.11 | +25:50:40.5 | HIP 32873 | 20.05 |
| 2026-07-30 00:00 | 06:49:53.76 | +25:45:32.0 | HIP 32874 | 15.01 |
| 2026-07-30 12:00 | 06:50:15.32 | +25:40:23.1 | HIP 32874 | 11.44 |
| 2026-07-31 00:00 | 06:50:36.77 | +25:35:13.9 | HIP 32874 | 11.70 |
| 2026-07-31 12:00 | 06:50:58.12 | +25:30:04.2 | HIP 32874 | 15.59 |
| 2026-08-01 00:00 | 06:51:19.37 | +25:24:54.2 | HIP 32964 | 17.26 |
| 2026-08-01 12:00 | 06:51:40.51 | +25:19:43.8 | HIP 32942 | 16.85 |
| 2026-08-02 00:00 | 06:52:01.55 | +25:14:33.0 | HIP 32942 | 12.35 |
| 2026-08-02 12:00 | 06:52:22.48 | +25:09:21.7 | HIP 32942 | 10.94 |
| 2026-08-03 00:00 | 06:52:43.31 | +25:04:10.1 | HIP 33011 | 6.07 |
| 2026-08-03 12:00 | 06:53:04.03 | +24:58:58.0 | HIP 33011 | 4.38 |
| 2026-08-04 00:00 | 06:53:24.64 | +24:53:45.4 | HIP 33011 | 9.97 |
| 2026-08-04 12:00 | 06:53:45.14 | +24:48:32.5 | HIP 33011 | 16.65 |
| 2026-08-05 00:00 | 06:54:05.52 | +24:43:19.1 | HIP 33011 | 23.50 |
| 2026-08-05 12:00 | 06:54:25.80 | +24:38:05.2 | HIP 33212 | 23.66 |
| 2026-08-06 00:00 | 06:54:45.97 | +24:32:50.9 | HIP 33212 | 18.11 |
| 2026-08-06 12:00 | 06:55:06.02 | +24:27:36.1 | HIP 33212 | 13.90 |
| 2026-08-07 00:00 | 06:55:25.96 | +24:22:20.8 | HIP 33212 | 12.42 |
| 2026-08-07 12:00 | 06:55:45.78 | +24:17:05.0 | HIP 33397 | 14.10 |
| 2026-08-08 00:00 | 06:56:05.49 | +24:11:48.8 | HIP 33397 | 11.33 |
| 2026-08-08 12:00 | 06:56:25.08 | +24:06:32.0 | HIP 33397 | 12.43 |
| 2026-08-09 00:00 | 06:56:44.55 | +24:01:14.8 | HIP 33300 | 15.40 |
| 2026-08-09 12:00 | 06:57:03.90 | +23:55:57.0 | HIP 33300 | 20.32 |
| 2026-08-10 00:00 | 06:57:23.13 | +23:50:38.7 | HIP 33300 | 26.13 |
| 2026-08-10 12:00 | 06:57:42.23 | +23:45:19.9 | HIP 33300 | 32.35 |
| 2026-08-11 00:00 | 06:58:01.22 | +23:40:00.6 | HIP 33300 | 38.78 |
| 2026-08-11 12:00 | 06:58:20.07 | +23:34:40.7 | HIP 33757 | 33.22 |
| 2026-08-12 00:00 | 06:58:38.81 | +23:29:20.3 | HIP 33757 | 28.04 |
| 2026-08-12 12:00 | 06:58:57.41 | +23:23:59.3 | HIP 33757 | 23.76 |
| 2026-08-13 00:00 | 06:59:15.89 | +23:18:37.8 | HIP 33757 | 20.90 |
| 2026-08-13 12:00 | 06:59:34.24 | +23:13:15.7 | HIP 33757 | 20.10 |
| 2026-08-14 00:00 | 06:59:52.45 | +23:07:53.0 | HIP 33757 | 21.56 |
| 2026-08-14 12:00 | 07:00:10.54 | +23:02:29.7 | HIP 33757 | 24.88 |
| 2026-08-15 00:00 | 07:00:28.49 | +22:57:05.9 | HIP 33757 | 29.44 |
| 2026-08-15 12:00 | 07:00:46.31 | +22:51:41.4 | HIP 33757 | 34.75 |
| 2026-08-16 00:00 | 07:01:03.99 | +22:46:16.4 | HIP 33999 | 36.78 |
| 2026-08-16 12:00 | 07:01:21.53 | +22:40:50.8 | HIP 33999 | 30.46 |
| 2026-08-17 00:00 | 07:01:38.94 | +22:35:24.5 | HIP 33999 | 24.38 |
| 2026-08-17 12:00 | 07:01:56.21 | +22:29:57.6 | HIP 33999 | 18.82 |
| 2026-08-18 00:00 | 07:02:13.34 | +22:24:30.1 | HIP 33999 | 14.33 |
| 2026-08-18 12:00 | 07:02:30.33 | +22:19:02.0 | HIP 33999 | 12.18 |
| 2026-08-19 00:00 | 07:02:47.18 | +22:13:33.2 | HIP 33962 | 6.40 |