メタデータ
| 項目 |
値 |
| Designation |
C/2015 X5 (PANSTARRS) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2017-12-31T00:50:40.139520Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:20Z |
| Obs used |
227 |
| NEO |
- |
| M1 |
6.600 |
| K1 |
10.500 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2017-07-11.0000000 |
| e |
1.00304318 |
| q (au) |
6.801746 |
| a (au) |
-2235.080422 |
| i (deg) |
124.284533 |
| Ω (om, deg) |
122.311473 |
| ω (w, deg) |
27.750506 |
| M (ma, deg) |
-0.001614 |
等級
散乱 + 全体線形
$$
M_a = (6.073 + 3.992\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
6.073 |
| n |
3.992 |
| gf |
0.977 |
| gb |
-0.739 |
| k |
1.000 |
| δ90 |
9.974 |
| 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
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 2015-12-06 |
2017-12-23 |
+1.9144 |
-1.449 |
| 2018-01-05 |
2020-02-14 |
-8.6346 |
+7.072 |
log10 r = log10(太陽距離/AU)、Δ = 地球距離(AU)
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
21:36:58.83 |
+25:07:00.0 |
HIP 106746 |
15.00 |
| 2026-06-01 12:00 |
21:36:56.19 |
+25:07:31.4 |
HIP 106746 |
14.78 |
| 2026-06-02 00:00 |
21:36:53.49 |
+25:08:02.5 |
HIP 106746 |
14.60 |
| 2026-06-02 12:00 |
21:36:50.74 |
+25:08:33.2 |
HIP 106746 |
14.47 |
| 2026-06-03 00:00 |
21:36:47.94 |
+25:09:03.6 |
HIP 106746 |
14.40 |
| 2026-06-03 12:00 |
21:36:45.08 |
+25:09:33.7 |
HIP 106746 |
14.39 |
| 2026-06-04 00:00 |
21:36:42.17 |
+25:10:03.4 |
HIP 106746 |
14.44 |
| 2026-06-04 12:00 |
21:36:39.21 |
+25:10:32.8 |
HIP 106746 |
14.55 |
| 2026-06-05 00:00 |
21:36:36.20 |
+25:11:01.8 |
HIP 106746 |
14.71 |
| 2026-06-05 12:00 |
21:36:33.13 |
+25:11:30.4 |
HIP 106746 |
14.94 |
| 2026-06-06 00:00 |
21:36:30.00 |
+25:11:58.7 |
HIP 106746 |
15.22 |
| 2026-06-06 12:00 |
21:36:26.83 |
+25:12:26.6 |
HIP 106746 |
15.55 |
| 2026-06-07 00:00 |
21:36:23.60 |
+25:12:54.1 |
HIP 106746 |
15.94 |
| 2026-06-07 12:00 |
21:36:20.32 |
+25:13:21.3 |
HIP 106746 |
16.37 |
| 2026-06-08 00:00 |
21:36:16.99 |
+25:13:48.1 |
HIP 106746 |
16.86 |
| 2026-06-08 12:00 |
21:36:13.61 |
+25:14:14.5 |
HIP 106746 |
17.39 |
| 2026-06-09 00:00 |
21:36:10.17 |
+25:14:40.5 |
HIP 106746 |
17.95 |
| 2026-06-09 12:00 |
21:36:06.68 |
+25:15:06.1 |
HIP 106746 |
18.56 |
| 2026-06-10 00:00 |
21:36:03.14 |
+25:15:31.4 |
HIP 106746 |
19.20 |
| 2026-06-10 12:00 |
21:35:59.55 |
+25:15:56.2 |
HIP 106746 |
19.88 |
| 2026-06-11 00:00 |
21:35:55.90 |
+25:16:20.6 |
HIP 106746 |
20.59 |
| 2026-06-11 12:00 |
21:35:52.21 |
+25:16:44.7 |
HIP 106746 |
21.32 |
| 2026-06-12 00:00 |
21:35:48.46 |
+25:17:08.3 |
HIP 106746 |
22.09 |
| 2026-06-12 12:00 |
21:35:44.67 |
+25:17:31.5 |
HIP 106746 |
22.87 |
| 2026-06-13 00:00 |
21:35:40.82 |
+25:17:54.3 |
HIP 106746 |
23.68 |
| 2026-06-13 12:00 |
21:35:36.92 |
+25:18:16.6 |
HIP 106746 |
24.52 |
| 2026-06-14 00:00 |
21:35:32.97 |
+25:18:38.5 |
HIP 106746 |
25.37 |
| 2026-06-14 12:00 |
21:35:28.97 |
+25:19:00.1 |
HIP 106746 |
26.24 |
| 2026-06-15 00:00 |
21:35:24.92 |
+25:19:21.1 |
HIP 106746 |
27.13 |
| 2026-06-15 12:00 |
21:35:20.83 |
+25:19:41.8 |
HIP 106746 |
28.04 |
| 2026-06-16 00:00 |
21:35:16.68 |
+25:20:02.0 |
HIP 106746 |
28.97 |
| 2026-06-16 12:00 |
21:35:12.48 |
+25:20:21.7 |
HIP 106746 |
29.91 |
| 2026-06-17 00:00 |
21:35:08.24 |
+25:20:41.0 |
HIP 106746 |
30.86 |
| 2026-06-17 12:00 |
21:35:03.94 |
+25:20:59.9 |
HIP 106746 |
31.83 |
| 2026-06-18 00:00 |
21:34:59.60 |
+25:21:18.3 |
HIP 106569 |
32.75 |
| 2026-06-18 12:00 |
21:34:55.21 |
+25:21:36.2 |
HIP 106569 |
32.43 |
| 2026-06-19 00:00 |
21:34:50.77 |
+25:21:53.7 |
HIP 106569 |
32.16 |
| 2026-06-19 12:00 |
21:34:46.28 |
+25:22:10.7 |
HIP 106569 |
31.93 |
| 2026-06-20 00:00 |
21:34:41.75 |
+25:22:27.3 |
HIP 106569 |
31.73 |
| 2026-06-20 12:00 |
21:34:37.17 |
+25:22:43.4 |
HIP 106569 |
31.59 |
| 2026-06-21 00:00 |
21:34:32.55 |
+25:22:59.0 |
HIP 106569 |
31.48 |
| 2026-06-21 12:00 |
21:34:27.88 |
+25:23:14.1 |
HIP 106569 |
31.42 |
| 2026-06-22 00:00 |
21:34:23.16 |
+25:23:28.8 |
HIP 106569 |
31.41 |