メタデータ
| 項目 |
値 |
| Designation |
C/2020 F5 (MASTER) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2021-03-22T10:15:53.521920Z |
| Orbit solution date (soln_date, UTC) |
2024-10-31T13:12:14Z |
| Obs used |
1861 |
| NEO |
- |
| M1 |
7.200 |
| K1 |
7.750 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2022-03-27.0000000 |
| e |
0.99509246 |
| q (au) |
4.324799 |
| a (au) |
881.256429 |
| i (deg) |
52.256923 |
| Ω (om, deg) |
350.527461 |
| ω (w, deg) |
310.997698 |
| M (ma, deg) |
0.013924 |
等級
散乱 + 全体線形
$$
M_a = (5.786 + 3.334\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
5.786 |
| n |
3.334 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
1.000 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-09-20 00:00 |
01:18:30.84 |
+61:10:22.8 |
HIP 6303 |
17.78 |
| 2026-09-20 12:00 |
01:18:17.46 |
+61:10:57.2 |
HIP 6303 |
19.45 |
| 2026-09-21 00:00 |
01:18:04.00 |
+61:11:30.5 |
HIP 6303 |
21.13 |
| 2026-09-21 12:00 |
01:17:50.49 |
+61:12:02.9 |
HIP 6303 |
22.83 |
| 2026-09-22 00:00 |
01:17:36.91 |
+61:12:34.3 |
HIP 6303 |
24.53 |
| 2026-09-22 12:00 |
01:17:23.26 |
+61:13:04.7 |
HIP 5829 |
25.35 |
| 2026-09-23 00:00 |
01:17:09.55 |
+61:13:34.1 |
HIP 5829 |
24.47 |
| 2026-09-23 12:00 |
01:16:55.78 |
+61:14:02.6 |
HIP 5829 |
23.67 |
| 2026-09-24 00:00 |
01:16:41.96 |
+61:14:30.0 |
HIP 5829 |
22.95 |
| 2026-09-24 12:00 |
01:16:28.07 |
+61:14:56.5 |
HIP 5829 |
22.33 |
| 2026-09-25 00:00 |
01:16:14.13 |
+61:15:22.0 |
HIP 5829 |
21.81 |
| 2026-09-25 12:00 |
01:16:00.14 |
+61:15:46.5 |
HIP 5829 |
21.40 |
| 2026-09-26 00:00 |
01:15:46.09 |
+61:16:09.9 |
HIP 5829 |
21.12 |
| 2026-09-26 12:00 |
01:15:31.99 |
+61:16:32.4 |
HIP 5658 |
20.88 |
| 2026-09-27 00:00 |
01:15:17.84 |
+61:16:53.9 |
HIP 5658 |
19.28 |
| 2026-09-27 12:00 |
01:15:03.64 |
+61:17:14.4 |
HIP 5658 |
17.70 |
| 2026-09-28 00:00 |
01:14:49.39 |
+61:17:33.8 |
HIP 5658 |
16.14 |
| 2026-09-28 12:00 |
01:14:35.10 |
+61:17:52.3 |
HIP 5658 |
14.61 |
| 2026-09-29 00:00 |
01:14:20.77 |
+61:18:09.7 |
HIP 5658 |
13.12 |
| 2026-09-29 12:00 |
01:14:06.39 |
+61:18:26.2 |
HIP 5658 |
11.69 |
| 2026-09-30 00:00 |
01:13:51.97 |
+61:18:41.6 |
HIP 5658 |
10.35 |
| 2026-09-30 12:00 |
01:13:37.51 |
+61:18:56.0 |
HIP 5658 |
9.14 |
| 2026-10-01 00:00 |
01:13:23.02 |
+61:19:09.4 |
HIP 5658 |
8.11 |
| 2026-10-01 12:00 |
01:13:08.48 |
+61:19:21.8 |
HIP 5658 |
7.34 |
| 2026-10-02 00:00 |
01:12:53.92 |
+61:19:33.2 |
HIP 5658 |
6.92 |
| 2026-10-02 12:00 |
01:12:39.32 |
+61:19:43.6 |
HIP 5658 |
6.93 |
| 2026-10-03 00:00 |
01:12:24.68 |
+61:19:52.9 |
HIP 5658 |
7.35 |
| 2026-10-03 12:00 |
01:12:10.02 |
+61:20:01.2 |
HIP 5658 |
8.13 |
| 2026-10-04 00:00 |
01:11:55.33 |
+61:20:08.5 |
HIP 5658 |
9.18 |
| 2026-10-04 12:00 |
01:11:40.62 |
+61:20:14.8 |
HIP 5658 |
10.41 |
| 2026-10-05 00:00 |
01:11:25.88 |
+61:20:20.0 |
HIP 5658 |
11.77 |
| 2026-10-05 12:00 |
01:11:11.11 |
+61:20:24.3 |
HIP 5658 |
13.22 |
| 2026-10-06 00:00 |
01:10:56.33 |
+61:20:27.5 |
HIP 5658 |
14.74 |
| 2026-10-06 12:00 |
01:10:41.52 |
+61:20:29.6 |
HIP 5445 |
14.22 |
| 2026-10-07 00:00 |
01:10:26.70 |
+61:20:30.8 |
HIP 5391 |
12.93 |
| 2026-10-07 12:00 |
01:10:11.87 |
+61:20:30.9 |
HIP 5391 |
11.55 |
| 2026-10-08 00:00 |
01:09:57.01 |
+61:20:30.0 |
HIP 5391 |
10.31 |
| 2026-10-08 12:00 |
01:09:42.15 |
+61:20:28.1 |
HIP 5391 |
9.26 |
| 2026-10-09 00:00 |
01:09:27.28 |
+61:20:25.2 |
HIP 5391 |
8.48 |
| 2026-10-09 12:00 |
01:09:12.39 |
+61:20:21.3 |
HIP 5391 |
8.03 |
| 2026-10-10 00:00 |
01:08:57.51 |
+61:20:16.3 |
HIP 5391 |
7.98 |
| 2026-10-10 12:00 |
01:08:42.61 |
+61:20:10.3 |
HIP 5391 |
8.34 |
| 2026-10-11 00:00 |
01:08:27.71 |
+61:20:03.3 |
HIP 5391 |
9.06 |