C/2025 J1 (Borisov)
メタデータ
| 項目 | 値 |
|---|---|
| Designation | C/2025 J1 (Borisov) |
| Type | C |
| Perihelion (tp_cal, UTC) | 2026-06-11T19:27:31.694400Z |
| Orbit solution date (soln_date, UTC) | 2026-05-08T13:42:11Z |
| Obs used | 889 |
| NEO | - |
| M1 | 8.200 |
| K1 | 10.750 |
| 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) | 2025-11-22.0000000 |
| e | 0.99712989 |
| q (au) | 3.580304 |
| a (au) | 1247.446063 |
| i (deg) | 95.444637 |
| Ω (om, deg) | 273.976289 |
| ω (w, deg) | 166.624168 |
| M (ma, deg) | 359.995485 |
等級
散乱 + 全体線形
$$ M_a = (9.267 + 5.775\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$
モデル定数
| 項目 | 値 |
|---|---|
| H0 | 9.267 |
| n | 5.775 |
| gf | 0.998 |
| gb | -0.822 |
| 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 | +3.9232 | -2.670 |
| 2025-10-22 | 2026-05-05 | -12.6493 | +7.390 |
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) |
|---|---|---|---|---|
| 2026-05-12 00:00 | 05:40:14.97 | +39:31:45.3 | HIP 26763 | 11.67 |
| 2026-05-12 12:00 | 05:40:43.18 | +39:25:46.0 | HIP 26763 | 13.10 |
| 2026-05-13 00:00 | 05:41:11.41 | +39:19:47.9 | HIP 26746 | 16.77 |
| 2026-05-13 12:00 | 05:41:39.66 | +39:13:51.0 | HIP 26746 | 13.22 |
| 2026-05-14 00:00 | 05:42:07.93 | +39:07:55.3 | HIP 26746 | 14.12 |
| 2026-05-14 12:00 | 05:42:36.22 | +39:02:00.8 | HIP 26789 | 15.85 |
| 2026-05-15 00:00 | 05:43:04.53 | +38:56:07.4 | HIP 26789 | 19.53 |
| 2026-05-15 12:00 | 05:43:32.85 | +38:50:15.1 | HIP 27154 | 22.95 |
| 2026-05-16 00:00 | 05:44:01.19 | +38:44:24.0 | HIP 27112 | 18.11 |
| 2026-05-16 12:00 | 05:44:29.54 | +38:38:34.0 | HIP 27112 | 10.16 |
| 2026-05-17 00:00 | 05:44:57.90 | +38:32:45.1 | HIP 27112 | 2.84 |
| 2026-05-17 12:00 | 05:45:26.28 | +38:26:57.3 | HIP 27112 | 6.47 |
| 2026-05-18 00:00 | 05:45:54.66 | +38:21:10.5 | HIP 27112 | 14.30 |
| 2026-05-18 12:00 | 05:46:23.06 | +38:15:24.8 | HIP 27300 | 12.99 |
| 2026-05-19 00:00 | 05:46:51.46 | +38:09:40.1 | HIP 27300 | 5.13 |
| 2026-05-19 12:00 | 05:47:19.87 | +38:03:56.5 | HIP 27300 | 3.49 |
| 2026-05-20 00:00 | 05:47:48.29 | +37:58:13.9 | HIP 27300 | 11.23 |
| 2026-05-20 12:00 | 05:48:16.71 | +37:52:32.3 | HIP 27300 | 19.18 |
| 2026-05-21 00:00 | 05:48:45.13 | +37:46:51.6 | HIP 27300 | 27.14 |
| 2026-05-21 12:00 | 05:49:13.56 | +37:41:12.0 | HIP 27639 | 31.44 |
| 2026-05-22 00:00 | 05:49:41.99 | +37:35:33.2 | HIP 27639 | 23.47 |
| 2026-05-22 12:00 | 05:50:10.42 | +37:29:55.5 | HIP 27639 | 15.52 |
| 2026-05-23 00:00 | 05:50:38.85 | +37:24:18.6 | HIP 27639 | 7.59 |
| 2026-05-23 12:00 | 05:51:07.28 | +37:18:42.7 | HIP 27639 | 1.04 |
| 2026-05-24 00:00 | 05:51:35.71 | +37:13:07.7 | HIP 27639 | 8.43 |
| 2026-05-24 12:00 | 05:52:04.13 | +37:07:33.6 | HIP 27639 | 16.35 |
| 2026-05-25 00:00 | 05:52:32.55 | +37:02:00.3 | HIP 27844 | 21.46 |
| 2026-05-25 12:00 | 05:53:00.97 | +36:56:27.9 | HIP 27844 | 24.50 |
| 2026-05-26 00:00 | 05:53:29.38 | +36:50:56.4 | HIP 28005 | 28.10 |
| 2026-05-26 12:00 | 05:53:57.78 | +36:45:25.7 | HIP 28043 | 24.95 |
| 2026-05-27 00:00 | 05:54:26.18 | +36:39:55.8 | HIP 28043 | 23.41 |
| 2026-05-27 12:00 | 05:54:54.57 | +36:34:26.7 | HIP 27954 | 19.54 |
| 2026-05-28 00:00 | 05:55:22.95 | +36:28:58.5 | HIP 27954 | 15.37 |
| 2026-05-28 12:00 | 05:55:51.32 | +36:23:31.0 | HIP 27954 | 14.70 |
| 2026-05-29 00:00 | 05:56:19.68 | +36:18:04.2 | HIP 27954 | 17.92 |
| 2026-05-29 12:00 | 05:56:48.03 | +36:12:38.3 | HIP 28280 | 23.26 |
| 2026-05-30 00:00 | 05:57:16.38 | +36:07:13.1 | HIP 28194 | 20.76 |
| 2026-05-30 12:00 | 05:57:44.70 | +36:01:48.6 | HIP 28194 | 15.50 |
| 2026-05-31 00:00 | 05:58:13.02 | +35:56:24.8 | HIP 28194 | 13.19 |
| 2026-05-31 12:00 | 05:58:41.32 | +35:51:01.8 | HIP 28194 | 15.23 |
| 2026-06-01 00:00 | 05:59:09.61 | +35:45:39.4 | HIP 28388 | 18.70 |
| 2026-06-01 12:00 | 05:59:37.89 | +35:40:17.8 | HIP 28388 | 22.49 |
| 2026-06-02 00:00 | 06:00:06.15 | +35:34:56.8 | HIP 28506 | 22.81 |