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
$$
M_a = (6.183 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
6.183 |
| n |
6.000 |
| gf |
0.935 |
| gb |
-0.981 |
| k |
1.000 |
| δ90 |
7.598 |
| 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 |
17:19:43.46 |
-11:41:29.4 |
HIP 84729 |
19.49 |
| 2026-09-20 12:00 |
17:19:50.69 |
-11:42:15.9 |
HIP 84729 |
19.63 |
| 2026-09-21 00:00 |
17:19:58.04 |
-11:43:02.4 |
HIP 84729 |
19.98 |
| 2026-09-21 12:00 |
17:20:05.50 |
-11:43:48.9 |
HIP 84729 |
20.52 |
| 2026-09-22 00:00 |
17:20:13.07 |
-11:44:35.4 |
HIP 84928 |
20.80 |
| 2026-09-22 12:00 |
17:20:20.75 |
-11:45:21.8 |
HIP 84928 |
18.84 |
| 2026-09-23 00:00 |
17:20:28.54 |
-11:46:08.1 |
HIP 84928 |
16.86 |
| 2026-09-23 12:00 |
17:20:36.44 |
-11:46:54.5 |
HIP 84928 |
14.89 |
| 2026-09-24 00:00 |
17:20:44.45 |
-11:47:40.8 |
HIP 84928 |
12.93 |
| 2026-09-24 12:00 |
17:20:52.57 |
-11:48:27.0 |
HIP 84928 |
11.02 |
| 2026-09-25 00:00 |
17:21:00.80 |
-11:49:13.2 |
HIP 84928 |
9.18 |
| 2026-09-25 12:00 |
17:21:09.14 |
-11:49:59.3 |
HIP 84928 |
7.51 |
| 2026-09-26 00:00 |
17:21:17.59 |
-11:50:45.3 |
HIP 84928 |
6.15 |
| 2026-09-26 12:00 |
17:21:26.14 |
-11:51:31.3 |
HIP 84928 |
5.40 |
| 2026-09-27 00:00 |
17:21:34.80 |
-11:52:17.2 |
HIP 84928 |
5.53 |
| 2026-09-27 12:00 |
17:21:43.56 |
-11:53:03.1 |
HIP 84928 |
6.51 |
| 2026-09-28 00:00 |
17:21:52.43 |
-11:53:48.9 |
HIP 84928 |
8.06 |
| 2026-09-28 12:00 |
17:22:01.41 |
-11:54:34.6 |
HIP 84928 |
9.93 |
| 2026-09-29 00:00 |
17:22:10.49 |
-11:55:20.2 |
HIP 84928 |
11.99 |
| 2026-09-29 12:00 |
17:22:19.68 |
-11:56:05.7 |
HIP 84928 |
14.16 |
| 2026-09-30 00:00 |
17:22:28.97 |
-11:56:51.2 |
HIP 84928 |
16.41 |
| 2026-09-30 12:00 |
17:22:38.36 |
-11:57:36.6 |
HIP 84928 |
18.73 |
| 2026-10-01 00:00 |
17:22:47.86 |
-11:58:21.8 |
HIP 84928 |
21.09 |
| 2026-10-01 12:00 |
17:22:57.46 |
-11:59:07.0 |
HIP 85151 |
23.34 |
| 2026-10-02 00:00 |
17:23:07.16 |
-11:59:52.1 |
HIP 85151 |
22.37 |
| 2026-10-02 12:00 |
17:23:16.97 |
-12:00:37.1 |
HIP 85151 |
21.64 |
| 2026-10-03 00:00 |
17:23:26.87 |
-12:01:21.9 |
HIP 85151 |
21.16 |
| 2026-10-03 12:00 |
17:23:36.88 |
-12:02:06.7 |
HIP 85151 |
20.98 |
| 2026-10-04 00:00 |
17:23:46.99 |
-12:02:51.4 |
HIP 85151 |
21.10 |
| 2026-10-04 12:00 |
17:23:57.20 |
-12:03:35.9 |
HIP 85151 |
21.53 |
| 2026-10-05 00:00 |
17:24:07.51 |
-12:04:20.3 |
HIP 85151 |
22.25 |
| 2026-10-05 12:00 |
17:24:17.92 |
-12:05:04.6 |
HIP 85151 |
23.26 |
| 2026-10-06 00:00 |
17:24:28.42 |
-12:05:48.8 |
HIP 85151 |
24.51 |
| 2026-10-06 12:00 |
17:24:39.03 |
-12:06:32.8 |
HIP 85151 |
25.99 |
| 2026-10-07 00:00 |
17:24:49.74 |
-12:07:16.7 |
HIP 85151 |
27.66 |
| 2026-10-07 12:00 |
17:25:00.54 |
-12:08:00.5 |
HIP 85151 |
29.49 |
| 2026-10-08 00:00 |
17:25:11.44 |
-12:08:44.1 |
HIP 85151 |
31.47 |
| 2026-10-08 12:00 |
17:25:22.43 |
-12:09:27.6 |
HIP 85397 |
32.34 |
| 2026-10-09 00:00 |
17:25:33.52 |
-12:10:10.9 |
HIP 85397 |
29.85 |
| 2026-10-09 12:00 |
17:25:44.71 |
-12:10:54.1 |
HIP 85397 |
27.40 |
| 2026-10-10 00:00 |
17:25:55.99 |
-12:11:37.2 |
HIP 85397 |
25.03 |
| 2026-10-10 12:00 |
17:26:07.37 |
-12:12:20.0 |
HIP 85397 |
22.75 |
| 2026-10-11 00:00 |
17:26:18.84 |
-12:13:02.8 |
HIP 85397 |
20.61 |