メタデータ
| 項目 |
値 |
| Designation |
P/2020 B4 (Sheppard) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2021-11-25T07:31:50.350080Z |
| Orbit solution date (soln_date, UTC) |
2023-05-18T19:13:12Z |
| Obs used |
20 |
| NEO |
- |
| M1 |
7.600 |
| K1 |
13.750 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2020-01-26T04:22:00.480000Z |
| Discovery magnitude (MPC) |
22.50 r |
| Discovery observatory (MPC) |
807 · Cerro Tololo Observatory, La Serena |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2020-06-04.0000000 |
| e |
0.19253094 |
| q (au) |
6.438946 |
| a (au) |
7.974232 |
| i (deg) |
11.601007 |
| Ω (om, deg) |
186.003502 |
| ω (w, deg) |
342.456738 |
| M (ma, deg) |
336.394550 |
等級
散乱 + 全体線形
$$
M_a = (6.184 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
6.184 |
| n |
6.000 |
| gf |
0.935 |
| gb |
-0.981 |
| k |
1.000 |
| δ90 |
7.586 |
| 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) |
| 2026-03-26 00:00 |
17:46:49.29 |
-11:58:17.5 |
HIP 86818 |
35.94 |
| 2026-03-26 12:00 |
17:46:52.82 |
-11:57:29.5 |
HIP 86818 |
36.87 |
| 2026-03-27 00:00 |
17:46:56.22 |
-11:56:41.5 |
HIP 86818 |
37.79 |
| 2026-03-27 12:00 |
17:46:59.50 |
-11:55:53.3 |
HIP 86818 |
38.68 |
| 2026-03-28 00:00 |
17:47:02.64 |
-11:55:05.1 |
HIP 86818 |
39.56 |
| 2026-03-28 12:00 |
17:47:05.65 |
-11:54:16.8 |
HIP 86818 |
40.42 |
| 2026-03-29 00:00 |
17:47:08.53 |
-11:53:28.5 |
HIP 86818 |
41.25 |
| 2026-03-29 12:00 |
17:47:11.28 |
-11:52:40.1 |
HIP 86818 |
42.07 |
| 2026-03-30 00:00 |
17:47:13.89 |
-11:51:51.6 |
HIP 87213 |
41.45 |
| 2026-03-30 12:00 |
17:47:16.38 |
-11:51:03.1 |
HIP 87213 |
40.44 |
| 2026-03-31 00:00 |
17:47:18.74 |
-11:50:14.5 |
HIP 87213 |
39.45 |
| 2026-03-31 12:00 |
17:47:20.96 |
-11:49:25.9 |
HIP 87213 |
38.48 |
| 2026-04-01 00:00 |
17:47:23.05 |
-11:48:37.2 |
HIP 87213 |
37.54 |
| 2026-04-01 12:00 |
17:47:25.01 |
-11:47:48.5 |
HIP 87213 |
36.61 |
| 2026-04-02 00:00 |
17:47:26.84 |
-11:46:59.8 |
HIP 87213 |
35.71 |
| 2026-04-02 12:00 |
17:47:28.54 |
-11:46:11.0 |
HIP 87213 |
34.83 |
| 2026-04-03 00:00 |
17:47:30.11 |
-11:45:22.2 |
HIP 87213 |
33.97 |
| 2026-04-03 12:00 |
17:47:31.55 |
-11:44:33.4 |
HIP 87213 |
33.14 |
| 2026-04-04 00:00 |
17:47:32.85 |
-11:43:44.5 |
HIP 87213 |
32.33 |
| 2026-04-04 12:00 |
17:47:34.02 |
-11:42:55.7 |
HIP 87213 |
31.54 |
| 2026-04-05 00:00 |
17:47:35.06 |
-11:42:06.8 |
HIP 87213 |
30.79 |
| 2026-04-05 12:00 |
17:47:35.97 |
-11:41:17.9 |
HIP 87213 |
30.06 |
| 2026-04-06 00:00 |
17:47:36.75 |
-11:40:29.0 |
HIP 87213 |
29.36 |
| 2026-04-06 12:00 |
17:47:37.39 |
-11:39:40.1 |
HIP 87213 |
28.70 |
| 2026-04-07 00:00 |
17:47:37.91 |
-11:38:51.2 |
HIP 87213 |
28.06 |
| 2026-04-07 12:00 |
17:47:38.29 |
-11:38:02.3 |
HIP 87213 |
27.47 |
| 2026-04-08 00:00 |
17:47:38.54 |
-11:37:13.4 |
HIP 87213 |
26.90 |
| 2026-04-08 12:00 |
17:47:38.66 |
-11:36:24.5 |
HIP 87213 |
26.38 |
| 2026-04-09 00:00 |
17:47:38.65 |
-11:35:35.7 |
HIP 87213 |
25.90 |
| 2026-04-09 12:00 |
17:47:38.50 |
-11:34:46.9 |
HIP 87213 |
25.47 |
| 2026-04-10 00:00 |
17:47:38.23 |
-11:33:58.0 |
HIP 87213 |
25.08 |
| 2026-04-10 12:00 |
17:47:37.82 |
-11:33:09.3 |
HIP 87213 |
24.73 |
| 2026-04-11 00:00 |
17:47:37.28 |
-11:32:20.5 |
HIP 87213 |
24.44 |
| 2026-04-11 12:00 |
17:47:36.61 |
-11:31:31.8 |
HIP 87213 |
24.21 |
| 2026-04-12 00:00 |
17:47:35.81 |
-11:30:43.1 |
HIP 87213 |
24.03 |
| 2026-04-12 12:00 |
17:47:34.88 |
-11:29:54.5 |
HIP 87213 |
23.90 |
| 2026-04-13 00:00 |
17:47:33.81 |
-11:29:06.0 |
HIP 87213 |
23.84 |
| 2026-04-13 12:00 |
17:47:32.62 |
-11:28:17.4 |
HIP 87213 |
23.83 |
| 2026-04-14 00:00 |
17:47:31.30 |
-11:27:29.0 |
HIP 87213 |
23.89 |
| 2026-04-14 12:00 |
17:47:29.84 |
-11:26:40.6 |
HIP 87213 |
24.01 |
| 2026-04-15 00:00 |
17:47:28.26 |
-11:25:52.3 |
HIP 87213 |
24.20 |
| 2026-04-15 12:00 |
17:47:26.54 |
-11:25:04.0 |
HIP 87213 |
24.44 |
| 2026-04-16 00:00 |
17:47:24.70 |
-11:24:15.9 |
HIP 87213 |
24.75 |