メタデータ
| 項目 |
値 |
| Designation |
C/2019 Q4 (Borisov) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2019-12-08T13:16:05.885760Z |
| Orbit solution date (soln_date, UTC) |
2024-06-24T15:49:04Z |
| Obs used |
964 |
| NEO |
- |
| M1 |
13.800 |
| K1 |
4.500 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2019-08-30T01:03:19.872000Z |
| Discovery magnitude (MPC) |
17.80 R |
| 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) |
2020-01-05.0000000 |
| e |
3.35647578 |
| q (au) |
2.006521 |
| a (au) |
-0.851492 |
| i (deg) |
44.052642 |
| Ω (om, deg) |
308.147729 |
| ω (w, deg) |
209.123686 |
| M (ma, deg) |
34.429470 |
等級
散乱 + 全体線形
$$
M_a = (14.853 + 2.256\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
14.853 |
| n |
2.256 |
| gf |
1.000 |
| gb |
-0.706 |
| 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 |
| 2018-12-13 |
2019-12-08 |
+1.5408 |
-0.661 |
| 2019-12-08 |
2020-03-05 |
+1.5873 |
-0.696 |
| 2020-03-05 |
2020-09-30 |
+12.2394 |
-6.131 |
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 |
17:56:20.04 |
-53:53:40.6 |
HIP 87793 |
18.87 |
| 2026-09-20 12:00 |
17:56:20.26 |
-53:53:20.8 |
HIP 87793 |
18.55 |
| 2026-09-21 00:00 |
17:56:20.51 |
-53:53:01.1 |
HIP 87793 |
18.23 |
| 2026-09-21 12:00 |
17:56:20.79 |
-53:52:41.4 |
HIP 87793 |
17.91 |
| 2026-09-22 00:00 |
17:56:21.11 |
-53:52:21.7 |
HIP 87793 |
17.59 |
| 2026-09-22 12:00 |
17:56:21.46 |
-53:52:02.0 |
HIP 87793 |
17.27 |
| 2026-09-23 00:00 |
17:56:21.85 |
-53:51:42.4 |
HIP 87793 |
16.96 |
| 2026-09-23 12:00 |
17:56:22.28 |
-53:51:22.7 |
HIP 87793 |
16.64 |
| 2026-09-24 00:00 |
17:56:22.74 |
-53:51:03.1 |
HIP 87793 |
16.33 |
| 2026-09-24 12:00 |
17:56:23.23 |
-53:50:43.5 |
HIP 87793 |
16.02 |
| 2026-09-25 00:00 |
17:56:23.76 |
-53:50:23.9 |
HIP 87793 |
15.71 |
| 2026-09-25 12:00 |
17:56:24.32 |
-53:50:04.3 |
HIP 87793 |
15.41 |
| 2026-09-26 00:00 |
17:56:24.92 |
-53:49:44.8 |
HIP 87793 |
15.11 |
| 2026-09-26 12:00 |
17:56:25.55 |
-53:49:25.3 |
HIP 87793 |
14.81 |
| 2026-09-27 00:00 |
17:56:26.22 |
-53:49:05.8 |
HIP 87793 |
14.51 |
| 2026-09-27 12:00 |
17:56:26.92 |
-53:48:46.3 |
HIP 87793 |
14.22 |
| 2026-09-28 00:00 |
17:56:27.66 |
-53:48:26.9 |
HIP 87793 |
13.93 |
| 2026-09-28 12:00 |
17:56:28.43 |
-53:48:07.5 |
HIP 87793 |
13.65 |
| 2026-09-29 00:00 |
17:56:29.23 |
-53:47:48.1 |
HIP 87793 |
13.37 |
| 2026-09-29 12:00 |
17:56:30.07 |
-53:47:28.8 |
HIP 87793 |
13.10 |
| 2026-09-30 00:00 |
17:56:30.94 |
-53:47:09.4 |
HIP 87793 |
12.83 |
| 2026-09-30 12:00 |
17:56:31.85 |
-53:46:50.2 |
HIP 87793 |
12.56 |
| 2026-10-01 00:00 |
17:56:32.79 |
-53:46:30.9 |
HIP 87793 |
12.31 |
| 2026-10-01 12:00 |
17:56:33.76 |
-53:46:11.7 |
HIP 87793 |
12.06 |
| 2026-10-02 00:00 |
17:56:34.77 |
-53:45:52.5 |
HIP 87793 |
11.82 |
| 2026-10-02 12:00 |
17:56:35.81 |
-53:45:33.4 |
HIP 87793 |
11.59 |
| 2026-10-03 00:00 |
17:56:36.88 |
-53:45:14.3 |
HIP 87793 |
11.36 |
| 2026-10-03 12:00 |
17:56:37.99 |
-53:44:55.3 |
HIP 87793 |
11.15 |
| 2026-10-04 00:00 |
17:56:39.13 |
-53:44:36.3 |
HIP 87793 |
10.94 |
| 2026-10-04 12:00 |
17:56:40.31 |
-53:44:17.3 |
HIP 87793 |
10.75 |
| 2026-10-05 00:00 |
17:56:41.52 |
-53:43:58.4 |
HIP 87793 |
10.57 |
| 2026-10-05 12:00 |
17:56:42.76 |
-53:43:39.5 |
HIP 87793 |
10.40 |
| 2026-10-06 00:00 |
17:56:44.03 |
-53:43:20.7 |
HIP 87793 |
10.25 |
| 2026-10-06 12:00 |
17:56:45.34 |
-53:43:01.9 |
HIP 87793 |
10.11 |
| 2026-10-07 00:00 |
17:56:46.68 |
-53:42:43.2 |
HIP 87793 |
9.98 |
| 2026-10-07 12:00 |
17:56:48.06 |
-53:42:24.5 |
HIP 87793 |
9.88 |
| 2026-10-08 00:00 |
17:56:49.47 |
-53:42:05.9 |
HIP 87793 |
9.79 |
| 2026-10-08 12:00 |
17:56:50.91 |
-53:41:47.3 |
HIP 87793 |
9.71 |
| 2026-10-09 00:00 |
17:56:52.38 |
-53:41:28.8 |
HIP 87793 |
9.66 |
| 2026-10-09 12:00 |
17:56:53.89 |
-53:41:10.3 |
HIP 87793 |
9.62 |
| 2026-10-10 00:00 |
17:56:55.42 |
-53:40:51.9 |
HIP 87793 |
9.61 |
| 2026-10-10 12:00 |
17:56:56.99 |
-53:40:33.6 |
HIP 87793 |
9.61 |
| 2026-10-11 00:00 |
17:56:58.60 |
-53:40:15.3 |
HIP 87793 |
9.63 |