C/2021 A6 (PANSTARRS)
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) |
| 2026-02-03 00:00 |
15:37:06.30 |
+49:49:44.3 |
HIP 76540 |
17.16 |
| 2026-02-03 12:00 |
15:37:13.65 |
+49:52:01.8 |
HIP 76540 |
14.57 |
| 2026-02-04 00:00 |
15:37:20.89 |
+49:54:19.8 |
HIP 76540 |
12.00 |
| 2026-02-04 12:00 |
15:37:28.03 |
+49:56:38.1 |
HIP 76540 |
9.42 |
| 2026-02-05 00:00 |
15:37:35.05 |
+49:58:56.7 |
HIP 76540 |
6.85 |
| 2026-02-05 12:00 |
15:37:41.97 |
+50:01:15.6 |
HIP 76540 |
4.29 |
| 2026-02-06 00:00 |
15:37:48.77 |
+50:03:34.8 |
HIP 76540 |
1.75 |
| 2026-02-06 12:00 |
15:37:55.46 |
+50:05:54.3 |
HIP 76540 |
0.94 |
| 2026-02-07 00:00 |
15:38:02.05 |
+50:08:14.2 |
HIP 76540 |
3.44 |
| 2026-02-07 12:00 |
15:38:08.52 |
+50:10:34.3 |
HIP 76540 |
5.98 |
| 2026-02-08 00:00 |
15:38:14.87 |
+50:12:54.6 |
HIP 76540 |
8.53 |
| 2026-02-08 12:00 |
15:38:21.12 |
+50:15:15.3 |
HIP 76594 |
10.36 |
| 2026-02-09 00:00 |
15:38:27.25 |
+50:17:36.2 |
HIP 76594 |
7.88 |
| 2026-02-09 12:00 |
15:38:33.27 |
+50:19:57.4 |
HIP 76594 |
5.45 |
| 2026-02-10 00:00 |
15:38:39.17 |
+50:22:18.8 |
HIP 76594 |
3.19 |
| 2026-02-10 12:00 |
15:38:44.96 |
+50:24:40.4 |
HIP 76594 |
1.86 |
| 2026-02-11 00:00 |
15:38:50.63 |
+50:27:02.2 |
HIP 76594 |
3.09 |
| 2026-02-11 12:00 |
15:38:56.18 |
+50:29:24.3 |
HIP 76594 |
5.32 |
| 2026-02-12 00:00 |
15:39:01.62 |
+50:31:46.5 |
HIP 76594 |
7.72 |
| 2026-02-12 12:00 |
15:39:06.95 |
+50:34:09.0 |
HIP 76594 |
10.18 |
| 2026-02-13 00:00 |
15:39:12.15 |
+50:36:31.6 |
HIP 76594 |
12.66 |
| 2026-02-13 12:00 |
15:39:17.24 |
+50:38:54.4 |
HIP 76594 |
15.14 |
| 2026-02-14 00:00 |
15:39:22.21 |
+50:41:17.3 |
HIP 76594 |
17.62 |
| 2026-02-14 12:00 |
15:39:27.07 |
+50:43:40.4 |
HIP 76594 |
20.11 |
| 2026-02-15 00:00 |
15:39:31.80 |
+50:46:03.7 |
HIP 76594 |
22.59 |
| 2026-02-15 12:00 |
15:39:36.41 |
+50:48:27.1 |
HIP 76594 |
25.07 |
| 2026-02-16 00:00 |
15:39:40.91 |
+50:50:50.5 |
HIP 76594 |
27.55 |
| 2026-02-16 12:00 |
15:39:45.28 |
+50:53:14.1 |
HIP 76923 |
29.75 |
| 2026-02-17 00:00 |
15:39:49.54 |
+50:55:37.8 |
HIP 76923 |
27.93 |
| 2026-02-17 12:00 |
15:39:53.67 |
+50:58:01.6 |
HIP 76923 |
26.25 |
| 2026-02-18 00:00 |
15:39:57.69 |
+51:00:25.5 |
HIP 76923 |
24.72 |
| 2026-02-18 12:00 |
15:40:01.58 |
+51:02:49.4 |
HIP 76923 |
23.37 |
| 2026-02-19 00:00 |
15:40:05.35 |
+51:05:13.4 |
HIP 76923 |
22.23 |
| 2026-02-19 12:00 |
15:40:09.00 |
+51:07:37.4 |
HIP 76923 |
21.35 |
| 2026-02-20 00:00 |
15:40:12.53 |
+51:10:01.4 |
HIP 76923 |
20.74 |
| 2026-02-20 12:00 |
15:40:15.93 |
+51:12:25.5 |
HIP 76923 |
20.43 |
| 2026-02-21 00:00 |
15:40:19.21 |
+51:14:49.5 |
HIP 76923 |
20.43 |
| 2026-02-21 12:00 |
15:40:22.37 |
+51:17:13.6 |
HIP 76923 |
20.75 |
| 2026-02-22 00:00 |
15:40:25.41 |
+51:19:37.7 |
HIP 76624 |
20.50 |
| 2026-02-22 12:00 |
15:40:28.33 |
+51:22:01.7 |
HIP 76624 |
19.21 |
| 2026-02-23 00:00 |
15:40:31.12 |
+51:24:25.7 |
HIP 76624 |
18.15 |
| 2026-02-23 12:00 |
15:40:33.79 |
+51:26:49.6 |
HIP 76624 |
17.34 |
| 2026-02-24 00:00 |
15:40:36.33 |
+51:29:13.5 |
HIP 76624 |
16.84 |