メタデータ
| 項目 |
値 |
| Designation |
C/2015 A2 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2015-08-30T11:44:29.256000Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:05Z |
| Obs used |
23 |
| NEO |
- |
| M1 |
14.300 |
| 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) |
2015-01-10.0000000 |
| e |
1.01374666 |
| q (au) |
5.266785 |
| a (au) |
-383.131941 |
| i (deg) |
108.899105 |
| Ω (om, deg) |
258.474274 |
| ω (w, deg) |
212.370407 |
| M (ma, deg) |
-0.030555 |
等級
散乱 + 全体線形
$$
M_a = (5.673 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
5.673 |
| n |
6.000 |
| gf |
0.982 |
| gb |
-1.000 |
| k |
1.000 |
| δ90 |
9.908 |
| 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 |
17:59:13.50 |
-47:22:27.9 |
HIP 88091 |
11.92 |
| 2026-03-26 12:00 |
17:59:12.42 |
-47:22:49.0 |
HIP 88091 |
11.62 |
| 2026-03-27 00:00 |
17:59:11.28 |
-47:23:10.1 |
HIP 88091 |
11.32 |
| 2026-03-27 12:00 |
17:59:10.06 |
-47:23:31.2 |
HIP 88091 |
11.04 |
| 2026-03-28 00:00 |
17:59:08.79 |
-47:23:52.3 |
HIP 88091 |
10.77 |
| 2026-03-28 12:00 |
17:59:07.45 |
-47:24:13.3 |
HIP 88091 |
10.51 |
| 2026-03-29 00:00 |
17:59:06.04 |
-47:24:34.3 |
HIP 88091 |
10.27 |
| 2026-03-29 12:00 |
17:59:04.56 |
-47:24:55.3 |
HIP 88091 |
10.04 |
| 2026-03-30 00:00 |
17:59:03.02 |
-47:25:16.3 |
HIP 88091 |
9.83 |
| 2026-03-30 12:00 |
17:59:01.42 |
-47:25:37.2 |
HIP 88091 |
9.65 |
| 2026-03-31 00:00 |
17:58:59.75 |
-47:25:58.1 |
HIP 88091 |
9.48 |
| 2026-03-31 12:00 |
17:58:58.01 |
-47:26:18.9 |
HIP 88091 |
9.35 |
| 2026-04-01 00:00 |
17:58:56.21 |
-47:26:39.7 |
HIP 88091 |
9.23 |
| 2026-04-01 12:00 |
17:58:54.34 |
-47:27:00.4 |
HIP 88091 |
9.15 |
| 2026-04-02 00:00 |
17:58:52.41 |
-47:27:21.1 |
HIP 88091 |
9.10 |
| 2026-04-02 12:00 |
17:58:50.41 |
-47:27:41.8 |
HIP 88091 |
9.09 |
| 2026-04-03 00:00 |
17:58:48.35 |
-47:28:02.4 |
HIP 88091 |
9.10 |
| 2026-04-03 12:00 |
17:58:46.23 |
-47:28:22.9 |
HIP 88091 |
9.16 |
| 2026-04-04 00:00 |
17:58:44.03 |
-47:28:43.4 |
HIP 88091 |
9.25 |
| 2026-04-04 12:00 |
17:58:41.78 |
-47:29:03.8 |
HIP 88091 |
9.37 |
| 2026-04-05 00:00 |
17:58:39.45 |
-47:29:24.1 |
HIP 88091 |
9.53 |
| 2026-04-05 12:00 |
17:58:37.07 |
-47:29:44.4 |
HIP 88091 |
9.73 |
| 2026-04-06 00:00 |
17:58:34.62 |
-47:30:04.7 |
HIP 88091 |
9.96 |
| 2026-04-06 12:00 |
17:58:32.10 |
-47:30:24.8 |
HIP 88091 |
10.22 |
| 2026-04-07 00:00 |
17:58:29.52 |
-47:30:44.9 |
HIP 88091 |
10.51 |
| 2026-04-07 12:00 |
17:58:26.87 |
-47:31:04.9 |
HIP 88091 |
10.84 |
| 2026-04-08 00:00 |
17:58:24.17 |
-47:31:24.8 |
HIP 88091 |
11.19 |
| 2026-04-08 12:00 |
17:58:21.39 |
-47:31:44.7 |
HIP 88091 |
11.58 |
| 2026-04-09 00:00 |
17:58:18.55 |
-47:32:04.4 |
HIP 88091 |
11.98 |
| 2026-04-09 12:00 |
17:58:15.65 |
-47:32:24.1 |
HIP 88091 |
12.42 |
| 2026-04-10 00:00 |
17:58:12.69 |
-47:32:43.7 |
HIP 88091 |
12.87 |
| 2026-04-10 12:00 |
17:58:09.66 |
-47:33:03.2 |
HIP 88091 |
13.35 |
| 2026-04-11 00:00 |
17:58:06.57 |
-47:33:22.6 |
HIP 88091 |
13.85 |
| 2026-04-11 12:00 |
17:58:03.41 |
-47:33:41.9 |
HIP 88091 |
14.37 |
| 2026-04-12 00:00 |
17:58:00.19 |
-47:34:01.2 |
HIP 88091 |
14.91 |
| 2026-04-12 12:00 |
17:57:56.91 |
-47:34:20.3 |
HIP 88091 |
15.46 |
| 2026-04-13 00:00 |
17:57:53.56 |
-47:34:39.3 |
HIP 88091 |
16.03 |
| 2026-04-13 12:00 |
17:57:50.15 |
-47:34:58.2 |
HIP 87826 |
16.36 |
| 2026-04-14 00:00 |
17:57:46.68 |
-47:35:17.0 |
HIP 87826 |
16.01 |
| 2026-04-14 12:00 |
17:57:43.15 |
-47:35:35.7 |
HIP 87826 |
15.66 |
| 2026-04-15 00:00 |
17:57:39.55 |
-47:35:54.2 |
HIP 87826 |
15.33 |
| 2026-04-15 12:00 |
17:57:35.90 |
-47:36:12.7 |
HIP 87826 |
15.02 |
| 2026-04-16 00:00 |
17:57:32.18 |
-47:36:31.0 |
HIP 87826 |
14.71 |