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
$$
M_a = (7.933 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
7.933 |
| n |
6.000 |
| gf |
0.999 |
| gb |
-1.000 |
| k |
0.801 |
| δ90 |
9.160 |
| 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) |
| 2026-06-01 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 |
| 2026-06-02 12:00 |
07:37:54.93 |
+55:20:32.0 |
HIP 37178 |
8.94 |
| 2026-06-03 00:00 |
07:38:04.23 |
+55:19:06.2 |
HIP 37178 |
7.13 |
| 2026-06-03 12:00 |
07:38:13.59 |
+55:17:40.7 |
HIP 37178 |
5.42 |
| 2026-06-04 00:00 |
07:38:23.00 |
+55:16:15.6 |
HIP 37178 |
3.94 |
| 2026-06-04 12:00 |
07:38:32.46 |
+55:14:50.8 |
HIP 37178 |
3.07 |
| 2026-06-05 00:00 |
07:38:41.97 |
+55:13:26.4 |
HIP 37178 |
3.31 |
| 2026-06-05 12:00 |
07:38:51.54 |
+55:12:02.3 |
HIP 37178 |
4.50 |
| 2026-06-06 00:00 |
07:39:01.15 |
+55:10:38.6 |
HIP 37178 |
6.11 |
| 2026-06-06 12:00 |
07:39:10.82 |
+55:09:15.2 |
HIP 37178 |
7.88 |
| 2026-06-07 00:00 |
07:39:20.53 |
+55:07:52.2 |
HIP 37178 |
9.72 |
| 2026-06-07 12:00 |
07:39:30.29 |
+55:06:29.6 |
HIP 37178 |
11.61 |
| 2026-06-08 00:00 |
07:39:40.10 |
+55:05:07.3 |
HIP 37178 |
13.52 |
| 2026-06-08 12:00 |
07:39:49.96 |
+55:03:45.3 |
HIP 37178 |
15.45 |
| 2026-06-09 00:00 |
07:39:59.87 |
+55:02:23.7 |
HIP 37178 |
17.39 |
| 2026-06-09 12:00 |
07:40:09.82 |
+55:01:02.5 |
HIP 37449 |
18.31 |
| 2026-06-10 00:00 |
07:40:19.82 |
+54:59:41.7 |
HIP 37449 |
16.42 |
| 2026-06-10 12:00 |
07:40:29.86 |
+54:58:21.2 |
HIP 37449 |
14.56 |
| 2026-06-11 00:00 |
07:40:39.94 |
+54:57:01.1 |
HIP 37449 |
12.73 |
| 2026-06-11 12:00 |
07:40:50.07 |
+54:55:41.3 |
HIP 37449 |
10.96 |
| 2026-06-12 00:00 |
07:41:00.24 |
+54:54:21.9 |
HIP 37449 |
9.27 |
| 2026-06-12 12:00 |
07:41:10.45 |
+54:53:02.9 |
HIP 37449 |
7.72 |
| 2026-06-13 00:00 |
07:41:20.71 |
+54:51:44.3 |
HIP 37449 |
6.41 |
| 2026-06-13 12:00 |
07:41:31.00 |
+54:50:26.0 |
HIP 37501 |
5.10 |
| 2026-06-14 00:00 |
07:41:41.33 |
+54:49:08.1 |
HIP 37501 |
3.33 |
| 2026-06-14 12:00 |
07:41:51.71 |
+54:47:50.6 |
HIP 37501 |
1.97 |
| 2026-06-15 00:00 |
07:42:02.12 |
+54:46:33.5 |
HIP 37501 |
2.14 |
| 2026-06-15 12:00 |
07:42:12.57 |
+54:45:16.8 |
HIP 37501 |
3.62 |
| 2026-06-16 00:00 |
07:42:23.05 |
+54:44:00.4 |
HIP 37501 |
5.43 |
| 2026-06-16 12:00 |
07:42:33.57 |
+54:42:44.5 |
HIP 37501 |
7.33 |
| 2026-06-17 00:00 |
07:42:44.12 |
+54:41:28.9 |
HIP 37501 |
9.26 |
| 2026-06-17 12:00 |
07:42:54.71 |
+54:40:13.7 |
HIP 37501 |
11.22 |
| 2026-06-18 00:00 |
07:43:05.33 |
+54:38:58.9 |
HIP 37501 |
13.18 |
| 2026-06-18 12:00 |
07:43:15.99 |
+54:37:44.5 |
HIP 37501 |
15.14 |
| 2026-06-19 00:00 |
07:43:26.68 |
+54:36:30.5 |
HIP 37501 |
17.11 |
| 2026-06-19 12:00 |
07:43:37.39 |
+54:35:16.8 |
HIP 37501 |
19.09 |
| 2026-06-20 00:00 |
07:43:48.14 |
+54:34:03.6 |
HIP 37501 |
21.06 |
| 2026-06-20 12:00 |
07:43:58.92 |
+54:32:50.8 |
HIP 37501 |
23.04 |
| 2026-06-21 00:00 |
07:44:09.72 |
+54:31:38.4 |
HIP 37501 |
25.01 |
| 2026-06-21 12:00 |
07:44:20.56 |
+54:30:26.3 |
HIP 37860 |
24.02 |
| 2026-06-22 00:00 |
07:44:31.42 |
+54:29:14.7 |
HIP 37860 |
22.23 |