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) |
| 2026-07-29 00:00 |
21:26:52.70 |
+25:17:05.6 |
HIP 106080 |
33.59 |
| 2026-07-29 12:00 |
21:26:45.66 |
+25:16:39.3 |
HIP 106080 |
35.24 |
| 2026-07-30 00:00 |
21:26:38.61 |
+25:16:12.4 |
HIP 105660 |
34.27 |
| 2026-07-30 12:00 |
21:26:31.54 |
+25:15:44.9 |
HIP 105660 |
32.72 |
| 2026-07-31 00:00 |
21:26:24.47 |
+25:15:16.8 |
HIP 105660 |
31.17 |
| 2026-07-31 12:00 |
21:26:17.38 |
+25:14:48.2 |
HIP 105660 |
29.64 |
| 2026-08-01 00:00 |
21:26:10.28 |
+25:14:19.0 |
HIP 105660 |
28.12 |
| 2026-08-01 12:00 |
21:26:03.17 |
+25:13:49.2 |
HIP 105660 |
26.63 |
| 2026-08-02 00:00 |
21:25:56.06 |
+25:13:18.9 |
HIP 105660 |
25.15 |
| 2026-08-02 12:00 |
21:25:48.93 |
+25:12:48.0 |
HIP 105660 |
23.71 |
| 2026-08-03 00:00 |
21:25:41.79 |
+25:12:16.5 |
HIP 105660 |
22.30 |
| 2026-08-03 12:00 |
21:25:34.65 |
+25:11:44.5 |
HIP 105660 |
20.93 |
| 2026-08-04 00:00 |
21:25:27.50 |
+25:11:11.9 |
HIP 105660 |
19.62 |
| 2026-08-04 12:00 |
21:25:20.34 |
+25:10:38.7 |
HIP 105660 |
18.37 |
| 2026-08-05 00:00 |
21:25:13.17 |
+25:10:04.9 |
HIP 105660 |
17.21 |
| 2026-08-05 12:00 |
21:25:06.00 |
+25:09:30.6 |
HIP 105660 |
16.15 |
| 2026-08-06 00:00 |
21:24:58.83 |
+25:08:55.8 |
HIP 105660 |
15.21 |
| 2026-08-06 12:00 |
21:24:51.65 |
+25:08:20.3 |
HIP 105660 |
14.43 |
| 2026-08-07 00:00 |
21:24:44.46 |
+25:07:44.3 |
HIP 105660 |
13.83 |
| 2026-08-07 12:00 |
21:24:37.27 |
+25:07:07.8 |
HIP 105660 |
13.43 |
| 2026-08-08 00:00 |
21:24:30.08 |
+25:06:30.7 |
HIP 105660 |
13.26 |
| 2026-08-08 12:00 |
21:24:22.89 |
+25:05:53.0 |
HIP 105660 |
13.33 |
| 2026-08-09 00:00 |
21:24:15.69 |
+25:05:14.7 |
HIP 105660 |
13.63 |
| 2026-08-09 12:00 |
21:24:08.49 |
+25:04:36.0 |
HIP 105660 |
14.15 |
| 2026-08-10 00:00 |
21:24:01.29 |
+25:03:56.6 |
HIP 105660 |
14.87 |
| 2026-08-10 12:00 |
21:23:54.10 |
+25:03:16.7 |
HIP 105660 |
15.76 |
| 2026-08-11 00:00 |
21:23:46.90 |
+25:02:36.3 |
HIP 105660 |
16.79 |
| 2026-08-11 12:00 |
21:23:39.70 |
+25:01:55.3 |
HIP 105528 |
17.17 |
| 2026-08-12 00:00 |
21:23:32.51 |
+25:01:13.7 |
HIP 105528 |
15.61 |
| 2026-08-12 12:00 |
21:23:25.31 |
+25:00:31.7 |
HIP 105528 |
14.10 |
| 2026-08-13 00:00 |
21:23:18.12 |
+24:59:49.0 |
HIP 105528 |
12.66 |
| 2026-08-13 12:00 |
21:23:10.94 |
+24:59:05.9 |
HIP 105528 |
11.32 |
| 2026-08-14 00:00 |
21:23:03.75 |
+24:58:22.1 |
HIP 105528 |
10.12 |
| 2026-08-14 12:00 |
21:22:56.58 |
+24:57:37.9 |
HIP 105528 |
9.12 |
| 2026-08-15 00:00 |
21:22:49.40 |
+24:56:53.1 |
HIP 105528 |
8.39 |
| 2026-08-15 12:00 |
21:22:42.24 |
+24:56:07.8 |
HIP 105528 |
8.01 |
| 2026-08-16 00:00 |
21:22:35.08 |
+24:55:22.0 |
HIP 105510 |
7.27 |
| 2026-08-16 12:00 |
21:22:27.92 |
+24:54:35.6 |
HIP 105510 |
6.84 |
| 2026-08-17 00:00 |
21:22:20.78 |
+24:53:48.8 |
HIP 105510 |
6.88 |
| 2026-08-17 12:00 |
21:22:13.64 |
+24:53:01.4 |
HIP 105510 |
7.38 |
| 2026-08-18 00:00 |
21:22:06.51 |
+24:52:13.4 |
HIP 105510 |
8.26 |
| 2026-08-18 12:00 |
21:21:59.39 |
+24:51:25.0 |
HIP 105510 |
9.42 |
| 2026-08-19 00:00 |
21:21:52.28 |
+24:50:36.1 |
HIP 105482 |
10.26 |