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) |
| 2026-05-12 00:00 |
18:09:03.85 |
-54:26:27.1 |
HIP 88844 |
13.31 |
| 2026-05-12 12:00 |
18:09:00.69 |
-54:26:38.9 |
HIP 88844 |
13.21 |
| 2026-05-13 00:00 |
18:08:57.51 |
-54:26:50.7 |
HIP 88844 |
13.12 |
| 2026-05-13 12:00 |
18:08:54.30 |
-54:27:02.3 |
HIP 88801 |
12.81 |
| 2026-05-14 00:00 |
18:08:51.07 |
-54:27:13.7 |
HIP 88801 |
12.52 |
| 2026-05-14 12:00 |
18:08:47.82 |
-54:27:25.1 |
HIP 88801 |
12.23 |
| 2026-05-15 00:00 |
18:08:44.54 |
-54:27:36.3 |
HIP 88801 |
11.96 |
| 2026-05-15 12:00 |
18:08:41.23 |
-54:27:47.3 |
HIP 88801 |
11.70 |
| 2026-05-16 00:00 |
18:08:37.91 |
-54:27:58.2 |
HIP 88801 |
11.45 |
| 2026-05-16 12:00 |
18:08:34.56 |
-54:28:09.0 |
HIP 88801 |
11.22 |
| 2026-05-17 00:00 |
18:08:31.19 |
-54:28:19.6 |
HIP 88801 |
11.00 |
| 2026-05-17 12:00 |
18:08:27.80 |
-54:28:30.1 |
HIP 88802 |
10.55 |
| 2026-05-18 00:00 |
18:08:24.38 |
-54:28:40.4 |
HIP 88802 |
10.10 |
| 2026-05-18 12:00 |
18:08:20.95 |
-54:28:50.6 |
HIP 88802 |
9.65 |
| 2026-05-19 00:00 |
18:08:17.49 |
-54:29:00.7 |
HIP 88802 |
9.22 |
| 2026-05-19 12:00 |
18:08:14.01 |
-54:29:10.6 |
HIP 88802 |
8.80 |
| 2026-05-20 00:00 |
18:08:10.51 |
-54:29:20.3 |
HIP 88802 |
8.38 |
| 2026-05-20 12:00 |
18:08:06.99 |
-54:29:29.9 |
HIP 88802 |
7.99 |
| 2026-05-21 00:00 |
18:08:03.46 |
-54:29:39.4 |
HIP 88802 |
7.61 |
| 2026-05-21 12:00 |
18:07:59.90 |
-54:29:48.6 |
HIP 88802 |
7.25 |
| 2026-05-22 00:00 |
18:07:56.32 |
-54:29:57.8 |
HIP 88802 |
6.92 |
| 2026-05-22 12:00 |
18:07:52.72 |
-54:30:06.8 |
HIP 88802 |
6.62 |
| 2026-05-23 00:00 |
18:07:49.11 |
-54:30:15.6 |
HIP 88802 |
6.35 |
| 2026-05-23 12:00 |
18:07:45.47 |
-54:30:24.3 |
HIP 88802 |
6.12 |
| 2026-05-24 00:00 |
18:07:41.82 |
-54:30:32.8 |
HIP 88802 |
5.94 |
| 2026-05-24 12:00 |
18:07:38.15 |
-54:30:41.2 |
HIP 88802 |
5.80 |
| 2026-05-25 00:00 |
18:07:34.47 |
-54:30:49.4 |
HIP 88802 |
5.72 |
| 2026-05-25 12:00 |
18:07:30.76 |
-54:30:57.5 |
HIP 88802 |
5.69 |
| 2026-05-26 00:00 |
18:07:27.04 |
-54:31:05.4 |
HIP 88802 |
5.72 |
| 2026-05-26 12:00 |
18:07:23.31 |
-54:31:13.2 |
HIP 88802 |
5.80 |
| 2026-05-27 00:00 |
18:07:19.55 |
-54:31:20.8 |
HIP 88802 |
5.94 |
| 2026-05-27 12:00 |
18:07:15.78 |
-54:31:28.2 |
HIP 88802 |
6.13 |
| 2026-05-28 00:00 |
18:07:12.00 |
-54:31:35.5 |
HIP 88802 |
6.37 |
| 2026-05-28 12:00 |
18:07:08.20 |
-54:31:42.6 |
HIP 88802 |
6.65 |
| 2026-05-29 00:00 |
18:07:04.39 |
-54:31:49.5 |
HIP 88802 |
6.97 |
| 2026-05-29 12:00 |
18:07:00.56 |
-54:31:56.3 |
HIP 88802 |
7.32 |
| 2026-05-30 00:00 |
18:06:56.71 |
-54:32:02.9 |
HIP 88802 |
7.71 |
| 2026-05-30 12:00 |
18:06:52.86 |
-54:32:09.4 |
HIP 88802 |
8.11 |
| 2026-05-31 00:00 |
18:06:48.99 |
-54:32:15.7 |
HIP 88802 |
8.54 |
| 2026-05-31 12:00 |
18:06:45.10 |
-54:32:21.8 |
HIP 88802 |
8.98 |
| 2026-06-01 00:00 |
18:06:41.20 |
-54:32:27.8 |
HIP 88802 |
9.45 |
| 2026-06-01 12:00 |
18:06:37.29 |
-54:32:33.6 |
HIP 88802 |
9.92 |
| 2026-06-02 00:00 |
18:06:33.37 |
-54:32:39.3 |
HIP 88802 |
10.41 |