メタデータ
| 項目 |
値 |
| Designation |
P/2021 A5 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2020-11-13T00:03:53.236800Z |
| Orbit solution date (soln_date, UTC) |
2025-01-14T17:42:18Z |
| Obs used |
47 |
| NEO |
- |
| M1 |
15.000 |
| K1 |
10.000 |
| PC |
- |
| Discovery observation (MPC, UTC) |
2021-01-06T07:09:10.742400Z |
| Discovery magnitude (MPC) |
21.24 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) |
2021-01-05.0000000 |
| e |
0.14092491 |
| q (au) |
2.622101 |
| a (au) |
3.052238 |
| i (deg) |
18.186098 |
| Ω (om, deg) |
328.718645 |
| ω (w, deg) |
61.512717 |
| M (ma, deg) |
9.795583 |
等級
散乱 + 全体線形
$$
M_a = (16.273 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
16.273 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-0.501 |
| k |
1.000 |
| δ90 |
10.000 |
| 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
ファインディングチャート
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-07-29 00:00 |
05:10:01.37 |
+37:49:26.1 |
HIP 24013 |
9.24 |
| 2026-07-29 12:00 |
05:11:00.00 |
+37:51:34.3 |
HIP 24013 |
18.59 |
| 2026-07-30 00:00 |
05:11:58.56 |
+37:53:41.4 |
HIP 24303 |
14.13 |
| 2026-07-30 12:00 |
05:12:57.06 |
+37:55:47.5 |
HIP 24303 |
11.19 |
| 2026-07-31 00:00 |
05:13:55.49 |
+37:57:52.6 |
HIP 24352 |
9.83 |
| 2026-07-31 12:00 |
05:14:53.86 |
+37:59:56.7 |
HIP 24437 |
14.18 |
| 2026-08-01 00:00 |
05:15:52.15 |
+38:01:59.8 |
HIP 24437 |
19.33 |
| 2026-08-01 12:00 |
05:16:50.38 |
+38:04:01.9 |
HIP 24437 |
28.58 |
| 2026-08-02 00:00 |
05:17:48.54 |
+38:06:03.1 |
HIP 24837 |
20.21 |
| 2026-08-02 12:00 |
05:18:46.62 |
+38:08:03.3 |
HIP 24837 |
8.65 |
| 2026-08-03 00:00 |
05:19:44.63 |
+38:10:02.5 |
HIP 24837 |
3.15 |
| 2026-08-03 12:00 |
05:20:42.56 |
+38:12:00.8 |
HIP 24837 |
14.58 |
| 2026-08-04 00:00 |
05:21:40.42 |
+38:13:58.2 |
HIP 24837 |
26.10 |
| 2026-08-04 12:00 |
05:22:38.20 |
+38:15:54.5 |
HIP 25260 |
25.34 |
| 2026-08-05 00:00 |
05:23:35.90 |
+38:17:50.0 |
HIP 25260 |
17.46 |
| 2026-08-05 12:00 |
05:24:33.52 |
+38:19:44.5 |
HIP 25260 |
15.18 |
| 2026-08-06 00:00 |
05:25:31.06 |
+38:21:38.1 |
HIP 25380 |
12.38 |
| 2026-08-06 12:00 |
05:26:28.51 |
+38:23:30.8 |
HIP 25380 |
12.71 |
| 2026-08-07 00:00 |
05:27:25.88 |
+38:25:22.5 |
HIP 25380 |
20.72 |
| 2026-08-07 12:00 |
05:28:23.16 |
+38:27:13.4 |
HIP 25771 |
22.91 |
| 2026-08-08 00:00 |
05:29:20.35 |
+38:29:03.3 |
HIP 25771 |
14.44 |
| 2026-08-08 12:00 |
05:30:17.46 |
+38:30:52.4 |
HIP 25771 |
12.25 |
| 2026-08-09 00:00 |
05:31:14.46 |
+38:32:40.6 |
HIP 25877 |
13.71 |
| 2026-08-09 12:00 |
05:32:11.38 |
+38:34:27.9 |
HIP 25877 |
17.61 |
| 2026-08-10 00:00 |
05:33:08.20 |
+38:36:14.3 |
HIP 26051 |
11.39 |
| 2026-08-10 12:00 |
05:34:04.92 |
+38:37:59.9 |
HIP 26051 |
11.70 |
| 2026-08-11 00:00 |
05:35:01.54 |
+38:39:44.6 |
HIP 26080 |
19.73 |
| 2026-08-11 12:00 |
05:35:58.06 |
+38:41:28.4 |
HIP 26293 |
19.97 |
| 2026-08-12 00:00 |
05:36:54.48 |
+38:43:11.5 |
HIP 26409 |
17.48 |
| 2026-08-12 12:00 |
05:37:50.80 |
+38:44:53.7 |
HIP 26409 |
16.78 |
| 2026-08-13 00:00 |
05:38:47.00 |
+38:46:35.0 |
HIP 26409 |
22.43 |
| 2026-08-13 12:00 |
05:39:43.10 |
+38:48:15.5 |
HIP 26789 |
20.70 |
| 2026-08-14 00:00 |
05:40:39.09 |
+38:49:55.3 |
HIP 26789 |
9.94 |
| 2026-08-14 12:00 |
05:41:34.97 |
+38:51:34.2 |
HIP 26789 |
3.55 |
| 2026-08-15 00:00 |
05:42:30.74 |
+38:53:12.3 |
HIP 26789 |
12.95 |
| 2026-08-15 12:00 |
05:43:26.39 |
+38:54:49.7 |
HIP 27154 |
22.98 |
| 2026-08-16 00:00 |
05:44:21.92 |
+38:56:26.2 |
HIP 27154 |
12.06 |
| 2026-08-16 12:00 |
05:45:17.34 |
+38:58:02.0 |
HIP 27154 |
1.19 |
| 2026-08-17 00:00 |
05:46:12.64 |
+38:59:37.0 |
HIP 27228 |
4.90 |
| 2026-08-17 12:00 |
05:47:07.82 |
+39:01:11.3 |
HIP 27327 |
2.86 |
| 2026-08-18 00:00 |
05:48:02.87 |
+39:02:44.8 |
HIP 27327 |
8.96 |
| 2026-08-18 12:00 |
05:48:57.81 |
+39:04:17.5 |
HIP 27483 |
7.02 |
| 2026-08-19 00:00 |
05:49:52.61 |
+39:05:49.6 |
HIP 27483 |
9.60 |