メタデータ
| 項目 |
値 |
| Designation |
P/2020 S7 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2020-11-18T00:51:10.647360Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:34:12Z |
| Obs used |
126 |
| NEO |
- |
| M1 |
14.600 |
| K1 |
10.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2020-09-16T08:31:24.960000Z |
| Discovery magnitude (MPC) |
20.80 w |
| Discovery observatory (MPC) |
F51 · Pan-STARRS 1, Haleakala |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2020-09-29.0000000 |
| e |
0.41057912 |
| q (au) |
2.961017 |
| a (au) |
5.023604 |
| i (deg) |
16.091824 |
| Ω (om, deg) |
328.018227 |
| ω (w, deg) |
40.397306 |
| M (ma, deg) |
355.620147 |
等級
散乱 + 全体線形
$$
M_a = (11.245 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
11.245 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-0.500 |
| 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) |
| 2026-03-26 00:00 |
11:53:12.99 |
-11:13:58.2 |
HIP 57869 |
16.07 |
| 2026-03-26 12:00 |
11:52:59.49 |
-11:12:49.5 |
HIP 57869 |
13.39 |
| 2026-03-27 00:00 |
11:52:46.01 |
-11:11:40.4 |
HIP 57869 |
11.18 |
| 2026-03-27 12:00 |
11:52:32.56 |
-11:10:30.9 |
HIP 57869 |
9.76 |
| 2026-03-28 00:00 |
11:52:19.14 |
-11:09:21.0 |
HIP 57869 |
9.50 |
| 2026-03-28 12:00 |
11:52:05.75 |
-11:08:10.8 |
HIP 57869 |
10.47 |
| 2026-03-29 00:00 |
11:51:52.39 |
-11:07:00.1 |
HIP 57869 |
12.38 |
| 2026-03-29 12:00 |
11:51:39.06 |
-11:05:49.2 |
HIP 57800 |
10.40 |
| 2026-03-30 00:00 |
11:51:25.77 |
-11:04:37.8 |
HIP 57800 |
9.16 |
| 2026-03-30 12:00 |
11:51:12.51 |
-11:03:26.2 |
HIP 57800 |
9.15 |
| 2026-03-31 00:00 |
11:50:59.29 |
-11:02:14.2 |
HIP 57800 |
10.38 |
| 2026-03-31 12:00 |
11:50:46.11 |
-11:01:02.0 |
HIP 57712 |
9.51 |
| 2026-04-01 00:00 |
11:50:32.98 |
-10:59:49.4 |
HIP 57712 |
6.78 |
| 2026-04-01 12:00 |
11:50:19.88 |
-10:58:36.5 |
HIP 57712 |
5.04 |
| 2026-04-02 00:00 |
11:50:06.84 |
-10:57:23.4 |
HIP 57712 |
5.34 |
| 2026-04-02 12:00 |
11:49:53.83 |
-10:56:10.0 |
HIP 57712 |
7.41 |
| 2026-04-03 00:00 |
11:49:40.88 |
-10:54:56.4 |
HIP 57712 |
10.23 |
| 2026-04-03 12:00 |
11:49:27.98 |
-10:53:42.5 |
HIP 57712 |
13.33 |
| 2026-04-04 00:00 |
11:49:15.13 |
-10:52:28.5 |
HIP 57712 |
16.53 |
| 2026-04-04 12:00 |
11:49:02.33 |
-10:51:14.2 |
HIP 57712 |
19.79 |
| 2026-04-05 00:00 |
11:48:49.58 |
-10:49:59.7 |
HIP 57712 |
23.07 |
| 2026-04-05 12:00 |
11:48:36.89 |
-10:48:45.0 |
HIP 57625 |
22.78 |
| 2026-04-06 00:00 |
11:48:24.26 |
-10:47:30.1 |
HIP 57625 |
22.45 |
| 2026-04-06 12:00 |
11:48:11.69 |
-10:46:15.1 |
HIP 57482 |
20.83 |
| 2026-04-07 00:00 |
11:47:59.18 |
-10:44:59.9 |
HIP 57482 |
19.02 |
| 2026-04-07 12:00 |
11:47:46.74 |
-10:43:44.6 |
HIP 57482 |
17.67 |
| 2026-04-08 00:00 |
11:47:34.35 |
-10:42:29.1 |
HIP 57482 |
16.88 |
| 2026-04-08 12:00 |
11:47:22.04 |
-10:41:13.6 |
HIP 57482 |
16.71 |
| 2026-04-09 00:00 |
11:47:09.79 |
-10:39:57.9 |
HIP 57482 |
17.19 |
| 2026-04-09 12:00 |
11:46:57.61 |
-10:38:42.2 |
HIP 57482 |
18.24 |
| 2026-04-10 00:00 |
11:46:45.50 |
-10:37:26.3 |
HIP 57482 |
19.78 |
| 2026-04-10 12:00 |
11:46:33.46 |
-10:36:10.4 |
HIP 57472 |
20.65 |
| 2026-04-11 00:00 |
11:46:21.49 |
-10:34:54.5 |
HIP 57472 |
20.33 |
| 2026-04-11 12:00 |
11:46:09.60 |
-10:33:38.5 |
HIP 57472 |
20.49 |
| 2026-04-12 00:00 |
11:45:57.79 |
-10:32:22.5 |
HIP 57472 |
21.12 |
| 2026-04-12 12:00 |
11:45:46.06 |
-10:31:06.5 |
HIP 57472 |
22.18 |
| 2026-04-13 00:00 |
11:45:34.40 |
-10:29:50.4 |
HIP 57472 |
23.60 |
| 2026-04-13 12:00 |
11:45:22.83 |
-10:28:34.4 |
HIP 57218 |
22.74 |
| 2026-04-14 00:00 |
11:45:11.33 |
-10:27:18.4 |
HIP 57218 |
20.79 |
| 2026-04-14 12:00 |
11:44:59.92 |
-10:26:02.5 |
HIP 57218 |
19.15 |
| 2026-04-15 00:00 |
11:44:48.60 |
-10:24:46.6 |
HIP 57218 |
17.91 |
| 2026-04-15 12:00 |
11:44:37.37 |
-10:23:30.7 |
HIP 57218 |
17.14 |
| 2026-04-16 00:00 |
11:44:26.22 |
-10:22:15.0 |
HIP 57218 |
16.90 |