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) |
| 2026-03-26 00:00 |
07:30:43.65 |
+59:12:20.1 |
HIP 36525 |
12.47 |
| 2026-03-26 12:00 |
07:30:38.50 |
+59:10:34.9 |
HIP 36525 |
14.28 |
| 2026-03-27 00:00 |
07:30:33.50 |
+59:08:49.5 |
HIP 36525 |
16.10 |
| 2026-03-27 12:00 |
07:30:28.65 |
+59:07:03.9 |
HIP 36525 |
17.93 |
| 2026-03-28 00:00 |
07:30:23.95 |
+59:05:18.2 |
HIP 36525 |
19.77 |
| 2026-03-28 12:00 |
07:30:19.39 |
+59:03:32.4 |
HIP 36656 |
20.85 |
| 2026-03-29 00:00 |
07:30:14.98 |
+59:01:46.3 |
HIP 36656 |
20.21 |
| 2026-03-29 12:00 |
07:30:10.72 |
+59:00:00.2 |
HIP 36656 |
19.71 |
| 2026-03-30 00:00 |
07:30:06.60 |
+58:58:13.8 |
HIP 36656 |
19.36 |
| 2026-03-30 12:00 |
07:30:02.63 |
+58:56:27.4 |
HIP 36656 |
19.16 |
| 2026-03-31 00:00 |
07:29:58.81 |
+58:54:40.8 |
HIP 36656 |
19.12 |
| 2026-03-31 12:00 |
07:29:55.13 |
+58:52:54.1 |
HIP 36656 |
19.24 |
| 2026-04-01 00:00 |
07:29:51.59 |
+58:51:07.3 |
HIP 36656 |
19.52 |
| 2026-04-01 12:00 |
07:29:48.20 |
+58:49:20.4 |
HIP 36656 |
19.95 |
| 2026-04-02 00:00 |
07:29:44.95 |
+58:47:33.4 |
HIP 36656 |
20.51 |
| 2026-04-02 12:00 |
07:29:41.84 |
+58:45:46.3 |
HIP 36656 |
21.20 |
| 2026-04-03 00:00 |
07:29:38.87 |
+58:43:59.0 |
HIP 36656 |
22.01 |
| 2026-04-03 12:00 |
07:29:36.05 |
+58:42:11.7 |
HIP 36656 |
22.91 |
| 2026-04-04 00:00 |
07:29:33.37 |
+58:40:24.4 |
HIP 36656 |
23.91 |
| 2026-04-04 12:00 |
07:29:30.83 |
+58:38:36.9 |
HIP 36656 |
24.98 |
| 2026-04-05 00:00 |
07:29:28.42 |
+58:36:49.4 |
HIP 36488 |
24.84 |
| 2026-04-05 12:00 |
07:29:26.16 |
+58:35:01.8 |
HIP 36488 |
23.25 |
| 2026-04-06 00:00 |
07:29:24.04 |
+58:33:14.2 |
HIP 36488 |
21.68 |
| 2026-04-06 12:00 |
07:29:22.06 |
+58:31:26.5 |
HIP 36488 |
20.15 |
| 2026-04-07 00:00 |
07:29:20.21 |
+58:29:38.8 |
HIP 36488 |
18.66 |
| 2026-04-07 12:00 |
07:29:18.50 |
+58:27:51.0 |
HIP 36488 |
17.22 |
| 2026-04-08 00:00 |
07:29:16.93 |
+58:26:03.2 |
HIP 36488 |
15.85 |
| 2026-04-08 12:00 |
07:29:15.50 |
+58:24:15.3 |
HIP 36488 |
14.56 |
| 2026-04-09 00:00 |
07:29:14.20 |
+58:22:27.5 |
HIP 36488 |
13.37 |
| 2026-04-09 12:00 |
07:29:13.04 |
+58:20:39.6 |
HIP 36488 |
12.33 |
| 2026-04-10 00:00 |
07:29:12.02 |
+58:18:51.7 |
HIP 36488 |
11.46 |
| 2026-04-10 12:00 |
07:29:11.12 |
+58:17:03.8 |
HIP 36344 |
9.76 |
| 2026-04-11 00:00 |
07:29:10.37 |
+58:15:15.9 |
HIP 36344 |
8.02 |
| 2026-04-11 12:00 |
07:29:09.74 |
+58:13:28.0 |
HIP 36344 |
6.32 |
| 2026-04-12 00:00 |
07:29:09.25 |
+58:11:40.1 |
HIP 36344 |
4.71 |
| 2026-04-12 12:00 |
07:29:08.89 |
+58:09:52.3 |
HIP 36344 |
3.30 |
| 2026-04-13 00:00 |
07:29:08.66 |
+58:08:04.4 |
HIP 36344 |
2.48 |
| 2026-04-13 12:00 |
07:29:08.57 |
+58:06:16.6 |
HIP 36344 |
2.83 |
| 2026-04-14 00:00 |
07:29:08.60 |
+58:04:28.8 |
HIP 36344 |
4.05 |
| 2026-04-14 12:00 |
07:29:08.77 |
+58:02:41.0 |
HIP 36344 |
5.59 |
| 2026-04-15 00:00 |
07:29:09.06 |
+58:00:53.3 |
HIP 36344 |
7.26 |
| 2026-04-15 12:00 |
07:29:09.49 |
+57:59:05.6 |
HIP 36344 |
8.98 |
| 2026-04-16 00:00 |
07:29:10.04 |
+57:57:18.0 |
HIP 36344 |
10.73 |