メタデータ
| 項目 |
値 |
| Designation |
C/2020 K2 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2020-08-04T17:10:46.476480Z |
| Orbit solution date (soln_date, UTC) |
2021-07-01T22:12:49Z |
| Obs used |
87 |
| NEO |
- |
| M1 |
7.000 |
| K1 |
9.250 |
| PC |
0.030 |
| Discovery observation (MPC, UTC) |
2020-05-21T13:39:44.841600Z |
| Discovery magnitude (MPC) |
20.56 w |
| Discovery observatory (MPC) |
F52 · Pan-STARRS 2, Haleakala |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2020-07-25.0000000 |
| e |
1.00129323 |
| q (au) |
8.878219 |
| a (au) |
-6865.139277 |
| i (deg) |
91.035953 |
| Ω (om, deg) |
288.338902 |
| ω (w, deg) |
67.272622 |
| M (ma, deg) |
-0.000019 |
等級
散乱 + 全体線形
$$
M_a = (7.947 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
7.947 |
| n |
6.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.800 |
| δ90 |
9.994 |
| 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) |
| 2026-05-12 00:00 |
07:32:16.63 |
+56:27:03.5 |
HIP 36916 |
25.78 |
| 2026-05-12 12:00 |
07:32:22.89 |
+56:25:24.6 |
HIP 36916 |
24.83 |
| 2026-05-13 00:00 |
07:32:29.24 |
+56:23:46.0 |
HIP 36916 |
23.97 |
| 2026-05-13 12:00 |
07:32:35.67 |
+56:22:07.6 |
HIP 36916 |
23.22 |
| 2026-05-14 00:00 |
07:32:42.19 |
+56:20:29.4 |
HIP 36916 |
22.59 |
| 2026-05-14 12:00 |
07:32:48.80 |
+56:18:51.6 |
HIP 36916 |
22.08 |
| 2026-05-15 00:00 |
07:32:55.49 |
+56:17:14.0 |
HIP 36916 |
21.71 |
| 2026-05-15 12:00 |
07:33:02.26 |
+56:15:36.7 |
HIP 36916 |
21.48 |
| 2026-05-16 00:00 |
07:33:09.12 |
+56:13:59.6 |
HIP 36916 |
21.40 |
| 2026-05-16 12:00 |
07:33:16.06 |
+56:12:22.8 |
HIP 36916 |
21.47 |
| 2026-05-17 00:00 |
07:33:23.08 |
+56:10:46.3 |
HIP 36958 |
21.06 |
| 2026-05-17 12:00 |
07:33:30.18 |
+56:09:10.1 |
HIP 36958 |
19.92 |
| 2026-05-18 00:00 |
07:33:37.36 |
+56:07:34.1 |
HIP 36958 |
18.88 |
| 2026-05-18 12:00 |
07:33:44.62 |
+56:05:58.5 |
HIP 36958 |
17.97 |
| 2026-05-19 00:00 |
07:33:51.95 |
+56:04:23.1 |
HIP 36958 |
17.21 |
| 2026-05-19 12:00 |
07:33:59.37 |
+56:02:48.0 |
HIP 36958 |
16.62 |
| 2026-05-20 00:00 |
07:34:06.86 |
+56:01:13.2 |
HIP 36958 |
16.21 |
| 2026-05-20 12:00 |
07:34:14.42 |
+55:59:38.7 |
HIP 36958 |
16.00 |
| 2026-05-21 00:00 |
07:34:22.06 |
+55:58:04.5 |
HIP 36958 |
16.01 |
| 2026-05-21 12:00 |
07:34:29.78 |
+55:56:30.6 |
HIP 36958 |
16.23 |
| 2026-05-22 00:00 |
07:34:37.57 |
+55:54:57.0 |
HIP 36958 |
16.65 |
| 2026-05-22 12:00 |
07:34:45.42 |
+55:53:23.7 |
HIP 36958 |
17.26 |
| 2026-05-23 00:00 |
07:34:53.36 |
+55:51:50.7 |
HIP 37046 |
17.26 |
| 2026-05-23 12:00 |
07:35:01.36 |
+55:50:18.1 |
HIP 37046 |
15.67 |
| 2026-05-24 00:00 |
07:35:09.43 |
+55:48:45.7 |
HIP 37046 |
14.15 |
| 2026-05-24 12:00 |
07:35:17.56 |
+55:47:13.6 |
HIP 37046 |
12.73 |
| 2026-05-25 00:00 |
07:35:25.77 |
+55:45:41.9 |
HIP 37046 |
11.44 |
| 2026-05-25 12:00 |
07:35:34.04 |
+55:44:10.5 |
HIP 37046 |
10.34 |
| 2026-05-26 00:00 |
07:35:42.38 |
+55:42:39.4 |
HIP 37046 |
9.48 |
| 2026-05-26 12:00 |
07:35:50.79 |
+55:41:08.6 |
HIP 37046 |
8.95 |
| 2026-05-27 00:00 |
07:35:59.26 |
+55:39:38.1 |
HIP 37046 |
8.80 |
| 2026-05-27 12:00 |
07:36:07.79 |
+55:38:08.0 |
HIP 37046 |
9.06 |
| 2026-05-28 00:00 |
07:36:16.39 |
+55:36:38.2 |
HIP 37046 |
9.69 |
| 2026-05-28 12:00 |
07:36:25.05 |
+55:35:08.7 |
HIP 37046 |
10.63 |
| 2026-05-29 00:00 |
07:36:33.77 |
+55:33:39.5 |
HIP 37046 |
11.80 |
| 2026-05-29 12:00 |
07:36:42.56 |
+55:32:10.7 |
HIP 37046 |
13.15 |
| 2026-05-30 00:00 |
07:36:51.40 |
+55:30:42.2 |
HIP 37046 |
14.62 |
| 2026-05-30 12:00 |
07:37:00.30 |
+55:29:14.0 |
HIP 37046 |
16.18 |
| 2026-05-31 00:00 |
07:37:09.26 |
+55:27:46.1 |
HIP 37046 |
17.82 |
| 2026-05-31 12:00 |
07:37:18.28 |
+55:26:18.6 |
HIP 37178 |
16.50 |
| 2026-06-01 00:00 |
07:37:27.36 |
+55:24:51.5 |
HIP 37178 |
14.59 |
| 2026-06-01 12:00 |
07:37:36.50 |
+55:23:24.6 |
HIP 37178 |
12.69 |
| 2026-06-02 00:00 |
07:37:45.69 |
+55:21:58.1 |
HIP 37178 |
10.80 |