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
$$
M_a = (11.343 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
11.343 |
| n |
6.000 |
| gf |
0.984 |
| gb |
-0.955 |
| k |
1.000 |
| δ90 |
6.701 |
| 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 |
12:16:12.54 |
-12:16:25.4 |
HIP 59839 |
15.19 |
| 2026-09-20 12:00 |
12:16:29.69 |
-12:18:22.9 |
HIP 59839 |
17.56 |
| 2026-09-21 00:00 |
12:16:46.85 |
-12:20:20.6 |
HIP 59839 |
20.71 |
| 2026-09-21 12:00 |
12:17:04.03 |
-12:22:18.7 |
HIP 59839 |
24.35 |
| 2026-09-22 00:00 |
12:17:21.21 |
-12:24:17.1 |
HIP 59839 |
28.29 |
| 2026-09-22 12:00 |
12:17:38.41 |
-12:26:15.9 |
HIP 59839 |
32.41 |
| 2026-09-23 00:00 |
12:17:55.62 |
-12:28:14.9 |
HIP 59839 |
36.67 |
| 2026-09-23 12:00 |
12:18:12.84 |
-12:30:14.2 |
HIP 59839 |
41.02 |
| 2026-09-24 00:00 |
12:18:30.07 |
-12:32:13.8 |
HIP 60213 |
39.26 |
| 2026-09-24 12:00 |
12:18:47.30 |
-12:34:13.8 |
HIP 60213 |
34.62 |
| 2026-09-25 00:00 |
12:19:04.55 |
-12:36:14.0 |
HIP 60213 |
29.97 |
| 2026-09-25 12:00 |
12:19:21.80 |
-12:38:14.5 |
HIP 60213 |
25.32 |
| 2026-09-26 00:00 |
12:19:39.06 |
-12:40:15.3 |
HIP 60213 |
20.68 |
| 2026-09-26 12:00 |
12:19:56.33 |
-12:42:16.3 |
HIP 60213 |
16.05 |
| 2026-09-27 00:00 |
12:20:13.61 |
-12:44:17.7 |
HIP 60213 |
11.44 |
| 2026-09-27 12:00 |
12:20:30.89 |
-12:46:19.3 |
HIP 60213 |
6.92 |
| 2026-09-28 00:00 |
12:20:48.17 |
-12:48:21.2 |
HIP 60213 |
2.93 |
| 2026-09-28 12:00 |
12:21:05.46 |
-12:50:23.4 |
HIP 60213 |
3.61 |
| 2026-09-29 00:00 |
12:21:22.76 |
-12:52:25.9 |
HIP 60213 |
7.83 |
| 2026-09-29 12:00 |
12:21:40.06 |
-12:54:28.6 |
HIP 60213 |
12.39 |
| 2026-09-30 00:00 |
12:21:57.36 |
-12:56:31.6 |
HIP 60372 |
15.75 |
| 2026-09-30 12:00 |
12:22:14.67 |
-12:58:34.8 |
HIP 60372 |
11.29 |
| 2026-10-01 00:00 |
12:22:31.98 |
-13:00:38.3 |
HIP 60372 |
7.15 |
| 2026-10-01 12:00 |
12:22:49.29 |
-13:02:42.1 |
HIP 60372 |
4.31 |
| 2026-10-02 00:00 |
12:23:06.60 |
-13:04:46.1 |
HIP 60372 |
5.49 |
| 2026-10-02 12:00 |
12:23:23.91 |
-13:06:50.3 |
HIP 60372 |
9.26 |
| 2026-10-03 00:00 |
12:23:41.22 |
-13:08:54.8 |
HIP 60372 |
13.62 |
| 2026-10-03 12:00 |
12:23:58.53 |
-13:10:59.6 |
HIP 60372 |
18.15 |
| 2026-10-04 00:00 |
12:24:15.85 |
-13:13:04.6 |
HIP 60620 |
18.72 |
| 2026-10-04 12:00 |
12:24:33.15 |
-13:15:09.8 |
HIP 60620 |
14.03 |
| 2026-10-05 00:00 |
12:24:50.46 |
-13:17:15.2 |
HIP 60620 |
9.36 |
| 2026-10-05 12:00 |
12:25:07.77 |
-13:19:20.9 |
HIP 60620 |
4.75 |
| 2026-10-06 00:00 |
12:25:25.07 |
-13:21:26.8 |
HIP 60620 |
1.28 |
| 2026-10-06 12:00 |
12:25:42.37 |
-13:23:32.9 |
HIP 60620 |
5.00 |
| 2026-10-07 00:00 |
12:25:59.66 |
-13:25:39.3 |
HIP 60620 |
9.63 |
| 2026-10-07 12:00 |
12:26:16.95 |
-13:27:45.8 |
HIP 60620 |
14.30 |
| 2026-10-08 00:00 |
12:26:34.23 |
-13:29:52.6 |
HIP 60711 |
17.83 |
| 2026-10-08 12:00 |
12:26:51.51 |
-13:31:59.5 |
HIP 60711 |
16.41 |
| 2026-10-09 00:00 |
12:27:08.78 |
-13:34:06.7 |
HIP 60711 |
16.28 |
| 2026-10-09 12:00 |
12:27:26.04 |
-13:36:14.1 |
HIP 60711 |
17.46 |
| 2026-10-10 00:00 |
12:27:43.29 |
-13:38:21.6 |
HIP 60711 |
19.71 |
| 2026-10-10 12:00 |
12:28:00.53 |
-13:40:29.3 |
HIP 60711 |
22.72 |
| 2026-10-11 00:00 |
12:28:17.77 |
-13:42:37.3 |
HIP 60711 |
26.22 |