メタデータ
| 項目 |
値 |
| Designation |
C/2021 A6 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2021-05-04T03:17:13.050240Z |
| Orbit solution date (soln_date, UTC) |
2024-08-02T01:42:19Z |
| Obs used |
167 |
| NEO |
- |
| M1 |
5.100 |
| K1 |
12.250 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-01-08T14:28:45.120000Z |
| Discovery magnitude (MPC) |
20.89 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) |
2022-03-24.0000000 |
| e |
0.99923094 |
| q (au) |
7.928456 |
| a (au) |
10309.304354 |
| i (deg) |
75.612049 |
| Ω (om, deg) |
164.079307 |
| ω (w, deg) |
351.692611 |
| M (ma, deg) |
0.000305 |
等級
散乱 + 全体線形
$$
M_a = (5.230 + 4.625\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
5.230 |
| n |
4.625 |
| gf |
0.981 |
| gb |
-0.874 |
| k |
1.000 |
| δ90 |
9.949 |
| 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 |
15:25:47.06 |
+55:46:02.4 |
HIP 75470 |
11.28 |
| 2026-05-12 12:00 |
15:25:36.18 |
+55:46:27.5 |
HIP 75470 |
10.88 |
| 2026-05-13 00:00 |
15:25:25.30 |
+55:46:51.4 |
HIP 75470 |
10.69 |
| 2026-05-13 12:00 |
15:25:14.42 |
+55:47:14.1 |
HIP 75470 |
10.71 |
| 2026-05-14 00:00 |
15:25:03.54 |
+55:47:35.7 |
HIP 75470 |
10.94 |
| 2026-05-14 12:00 |
15:24:52.66 |
+55:47:56.1 |
HIP 75470 |
11.37 |
| 2026-05-15 00:00 |
15:24:41.78 |
+55:48:15.2 |
HIP 75470 |
11.97 |
| 2026-05-15 12:00 |
15:24:30.91 |
+55:48:33.2 |
HIP 75470 |
12.71 |
| 2026-05-16 00:00 |
15:24:20.04 |
+55:48:50.0 |
HIP 75470 |
13.58 |
| 2026-05-16 12:00 |
15:24:09.18 |
+55:49:05.6 |
HIP 75470 |
14.54 |
| 2026-05-17 00:00 |
15:23:58.33 |
+55:49:20.0 |
HIP 75470 |
15.59 |
| 2026-05-17 12:00 |
15:23:47.49 |
+55:49:33.2 |
HIP 75205 |
16.24 |
| 2026-05-18 00:00 |
15:23:36.66 |
+55:49:45.2 |
HIP 75205 |
15.05 |
| 2026-05-18 12:00 |
15:23:25.84 |
+55:49:56.1 |
HIP 75205 |
13.92 |
| 2026-05-19 00:00 |
15:23:15.04 |
+55:50:05.8 |
HIP 75205 |
12.86 |
| 2026-05-19 12:00 |
15:23:04.26 |
+55:50:14.2 |
HIP 75205 |
11.89 |
| 2026-05-20 00:00 |
15:22:53.49 |
+55:50:21.5 |
HIP 75205 |
11.03 |
| 2026-05-20 12:00 |
15:22:42.75 |
+55:50:27.7 |
HIP 75205 |
10.31 |
| 2026-05-21 00:00 |
15:22:32.02 |
+55:50:32.6 |
HIP 75205 |
9.75 |
| 2026-05-21 12:00 |
15:22:21.32 |
+55:50:36.4 |
HIP 75205 |
9.39 |
| 2026-05-22 00:00 |
15:22:10.64 |
+55:50:39.0 |
HIP 75205 |
9.24 |
| 2026-05-22 12:00 |
15:22:00.00 |
+55:50:40.5 |
HIP 75205 |
9.31 |
| 2026-05-23 00:00 |
15:21:49.37 |
+55:50:40.8 |
HIP 75205 |
9.60 |
| 2026-05-23 12:00 |
15:21:38.77 |
+55:50:39.9 |
HIP 75205 |
10.09 |
| 2026-05-24 00:00 |
15:21:28.20 |
+55:50:37.9 |
HIP 75205 |
10.74 |
| 2026-05-24 12:00 |
15:21:17.66 |
+55:50:34.7 |
HIP 75205 |
11.53 |
| 2026-05-25 00:00 |
15:21:07.16 |
+55:50:30.4 |
HIP 75205 |
12.44 |
| 2026-05-25 12:00 |
15:20:56.68 |
+55:50:24.9 |
HIP 75205 |
13.42 |
| 2026-05-26 00:00 |
15:20:46.24 |
+55:50:18.3 |
HIP 75205 |
14.48 |
| 2026-05-26 12:00 |
15:20:35.84 |
+55:50:10.5 |
HIP 75205 |
15.59 |
| 2026-05-27 00:00 |
15:20:25.48 |
+55:50:01.6 |
HIP 75205 |
16.74 |
| 2026-05-27 12:00 |
15:20:15.15 |
+55:49:51.6 |
HIP 75205 |
17.92 |
| 2026-05-28 00:00 |
15:20:04.86 |
+55:49:40.5 |
HIP 75205 |
19.13 |
| 2026-05-28 12:00 |
15:19:54.62 |
+55:49:28.2 |
HIP 75205 |
20.36 |
| 2026-05-29 00:00 |
15:19:44.41 |
+55:49:14.9 |
HIP 75205 |
21.60 |
| 2026-05-29 12:00 |
15:19:34.25 |
+55:49:00.4 |
HIP 75205 |
22.86 |
| 2026-05-30 00:00 |
15:19:24.13 |
+55:48:44.8 |
HIP 75205 |
24.13 |
| 2026-05-30 12:00 |
15:19:14.06 |
+55:48:28.0 |
HIP 75205 |
25.41 |
| 2026-05-31 00:00 |
15:19:04.04 |
+55:48:10.2 |
HIP 75205 |
26.69 |
| 2026-05-31 12:00 |
15:18:54.06 |
+55:47:51.3 |
HIP 75205 |
27.98 |
| 2026-06-01 00:00 |
15:18:44.13 |
+55:47:31.3 |
HIP 75205 |
29.27 |
| 2026-06-01 12:00 |
15:18:34.26 |
+55:47:10.2 |
HIP 75205 |
30.56 |
| 2026-06-02 00:00 |
15:18:24.43 |
+55:46:48.0 |
HIP 75205 |
31.86 |