メタデータ
| 項目 |
値 |
| Designation |
P/2018 A5 (PANSTARRS) |
| Type |
P |
| Perihelion (tp_cal, UTC) |
2017-09-23T19:44:28.916160Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:40Z |
| Obs used |
36 |
| NEO |
- |
| M1 |
17.700 |
| K1 |
4.500 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2017-12-11.0000000 |
| e |
0.52304780 |
| q (au) |
2.693821 |
| a (au) |
5.647990 |
| i (deg) |
23.577029 |
| Ω (om, deg) |
87.829721 |
| ω (w, deg) |
359.679511 |
| M (ma, deg) |
5.740433 |
等級
散乱 + 全体線形
$$
M_a = (17.815 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
17.815 |
| n |
2.000 |
| gf |
1.000 |
| gb |
-1.000 |
| k |
0.999 |
| δ90 |
1.000 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
19:37:24.35 |
-28:38:59.2 |
HIP 96566 |
11.76 |
| 2026-03-26 12:00 |
19:37:33.44 |
-28:39:24.3 |
HIP 96566 |
10.46 |
| 2026-03-27 00:00 |
19:37:42.42 |
-28:39:49.7 |
HIP 96566 |
9.41 |
| 2026-03-27 12:00 |
19:37:51.28 |
-28:40:15.5 |
HIP 96566 |
8.71 |
| 2026-03-28 00:00 |
19:38:00.04 |
-28:40:41.7 |
HIP 96566 |
8.42 |
| 2026-03-28 12:00 |
19:38:08.68 |
-28:41:08.3 |
HIP 96566 |
8.56 |
| 2026-03-29 00:00 |
19:38:17.20 |
-28:41:35.2 |
HIP 96566 |
9.11 |
| 2026-03-29 12:00 |
19:38:25.62 |
-28:42:02.5 |
HIP 96644 |
8.75 |
| 2026-03-30 00:00 |
19:38:33.91 |
-28:42:30.2 |
HIP 96644 |
7.80 |
| 2026-03-30 12:00 |
19:38:42.10 |
-28:42:58.2 |
HIP 96644 |
7.23 |
| 2026-03-31 00:00 |
19:38:50.16 |
-28:43:26.7 |
HIP 96644 |
7.14 |
| 2026-03-31 12:00 |
19:38:58.11 |
-28:43:55.5 |
HIP 96644 |
7.50 |
| 2026-04-01 00:00 |
19:39:05.94 |
-28:44:24.7 |
HIP 96644 |
8.26 |
| 2026-04-01 12:00 |
19:39:13.66 |
-28:44:54.3 |
HIP 96644 |
9.30 |
| 2026-04-02 00:00 |
19:39:21.26 |
-28:45:24.2 |
HIP 96644 |
10.52 |
| 2026-04-02 12:00 |
19:39:28.73 |
-28:45:54.6 |
HIP 96644 |
11.86 |
| 2026-04-03 00:00 |
19:39:36.09 |
-28:46:25.3 |
HIP 96644 |
13.28 |
| 2026-04-03 12:00 |
19:39:43.33 |
-28:46:56.4 |
HIP 96644 |
14.74 |
| 2026-04-04 00:00 |
19:39:50.45 |
-28:47:28.0 |
HIP 96644 |
16.22 |
| 2026-04-04 12:00 |
19:39:57.45 |
-28:47:59.8 |
HIP 96644 |
17.72 |
| 2026-04-05 00:00 |
19:40:04.33 |
-28:48:32.1 |
HIP 96644 |
19.22 |
| 2026-04-05 12:00 |
19:40:11.09 |
-28:49:04.8 |
HIP 96644 |
20.72 |
| 2026-04-06 00:00 |
19:40:17.72 |
-28:49:37.9 |
HIP 96899 |
20.44 |
| 2026-04-06 12:00 |
19:40:24.23 |
-28:50:11.3 |
HIP 96899 |
18.98 |
| 2026-04-07 00:00 |
19:40:30.62 |
-28:50:45.2 |
HIP 96899 |
17.56 |
| 2026-04-07 12:00 |
19:40:36.88 |
-28:51:19.4 |
HIP 96899 |
16.19 |
| 2026-04-08 00:00 |
19:40:43.02 |
-28:51:54.1 |
HIP 96899 |
14.87 |
| 2026-04-08 12:00 |
19:40:49.03 |
-28:52:29.1 |
HIP 96899 |
13.60 |
| 2026-04-09 00:00 |
19:40:54.92 |
-28:53:04.6 |
HIP 96899 |
12.39 |
| 2026-04-09 12:00 |
19:41:00.68 |
-28:53:40.4 |
HIP 96899 |
11.27 |
| 2026-04-10 00:00 |
19:41:06.32 |
-28:54:16.6 |
HIP 96899 |
10.24 |
| 2026-04-10 12:00 |
19:41:11.82 |
-28:54:53.3 |
HIP 96899 |
9.33 |
| 2026-04-11 00:00 |
19:41:17.20 |
-28:55:30.3 |
HIP 96899 |
8.57 |
| 2026-04-11 12:00 |
19:41:22.45 |
-28:56:07.7 |
HIP 96899 |
7.98 |
| 2026-04-12 00:00 |
19:41:27.57 |
-28:56:45.6 |
HIP 96899 |
7.60 |
| 2026-04-12 12:00 |
19:41:32.56 |
-28:57:23.8 |
HIP 96899 |
7.45 |
| 2026-04-13 00:00 |
19:41:37.43 |
-28:58:02.4 |
HIP 96899 |
7.52 |
| 2026-04-13 12:00 |
19:41:42.16 |
-28:58:41.5 |
HIP 96899 |
7.81 |
| 2026-04-14 00:00 |
19:41:46.76 |
-28:59:20.9 |
HIP 96899 |
8.29 |
| 2026-04-14 12:00 |
19:41:51.22 |
-29:00:00.8 |
HIP 96899 |
8.90 |
| 2026-04-15 00:00 |
19:41:55.56 |
-29:00:41.0 |
HIP 96899 |
9.63 |
| 2026-04-15 12:00 |
19:41:59.76 |
-29:01:21.7 |
HIP 96899 |
10.44 |
| 2026-04-16 00:00 |
19:42:03.83 |
-29:02:02.7 |
HIP 96899 |
11.30 |