メタデータ
| 項目 |
値 |
| Designation |
C/2015 G2 (MASTER) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2015-05-23T18:53:55.887360Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:33:09Z |
| Obs used |
562 |
| NEO |
- |
| M1 |
12.000 |
| K1 |
6.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2015-08-16.0000000 |
| e |
1.00039511 |
| q (au) |
0.779858 |
| a (au) |
-1973.798171 |
| i (deg) |
147.562721 |
| Ω (om, deg) |
110.058840 |
| ω (w, deg) |
257.458784 |
| M (ma, deg) |
0.000947 |
等級
散乱 + 全体線形
$$
M_a = (11.448 + 3.318\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
11.448 |
| n |
3.318 |
| gf |
1.000 |
| gb |
-0.627 |
| k |
0.956 |
| 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
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 2015-03-30 |
2015-04-10 |
-18.6339 |
+0.055 |
| 2015-04-10 |
2015-04-24 |
-23.7310 |
-0.653 |
| 2015-04-24 |
2015-05-23 |
+8.8729 |
-1.009 |
| 2015-05-23 |
2016-02-07 |
+2.0675 |
-1.196 |
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 |
03:07:31.49 |
+44:44:27.7 |
HIP 14668 |
22.10 |
| 2026-06-01 12:00 |
03:07:36.48 |
+44:44:52.1 |
HIP 14668 |
21.13 |
| 2026-06-02 00:00 |
03:07:41.45 |
+44:45:16.7 |
HIP 14668 |
20.16 |
| 2026-06-02 12:00 |
03:07:46.40 |
+44:45:41.5 |
HIP 14668 |
19.20 |
| 2026-06-03 00:00 |
03:07:51.34 |
+44:46:06.4 |
HIP 14668 |
18.24 |
| 2026-06-03 12:00 |
03:07:56.26 |
+44:46:31.5 |
HIP 14668 |
17.28 |
| 2026-06-04 00:00 |
03:08:01.16 |
+44:46:56.8 |
HIP 14668 |
16.33 |
| 2026-06-04 12:00 |
03:08:06.04 |
+44:47:22.2 |
HIP 14668 |
15.38 |
| 2026-06-05 00:00 |
03:08:10.91 |
+44:47:47.7 |
HIP 14668 |
14.43 |
| 2026-06-05 12:00 |
03:08:15.76 |
+44:48:13.4 |
HIP 14668 |
13.49 |
| 2026-06-06 00:00 |
03:08:20.59 |
+44:48:39.3 |
HIP 14668 |
12.56 |
| 2026-06-06 12:00 |
03:08:25.40 |
+44:49:05.3 |
HIP 14668 |
11.63 |
| 2026-06-07 00:00 |
03:08:30.19 |
+44:49:31.5 |
HIP 14668 |
10.72 |
| 2026-06-07 12:00 |
03:08:34.96 |
+44:49:57.8 |
HIP 14668 |
9.81 |
| 2026-06-08 00:00 |
03:08:39.71 |
+44:50:24.2 |
HIP 14668 |
8.91 |
| 2026-06-08 12:00 |
03:08:44.44 |
+44:50:50.8 |
HIP 14668 |
8.03 |
| 2026-06-09 00:00 |
03:08:49.15 |
+44:51:17.6 |
HIP 14668 |
7.18 |
| 2026-06-09 12:00 |
03:08:53.84 |
+44:51:44.5 |
HIP 14668 |
6.35 |
| 2026-06-10 00:00 |
03:08:58.50 |
+44:52:11.5 |
HIP 14668 |
5.56 |
| 2026-06-10 12:00 |
03:09:03.15 |
+44:52:38.7 |
HIP 14668 |
4.84 |
| 2026-06-11 00:00 |
03:09:07.77 |
+44:53:06.0 |
HIP 14668 |
4.20 |
| 2026-06-11 12:00 |
03:09:12.37 |
+44:53:33.5 |
HIP 14668 |
3.70 |
| 2026-06-12 00:00 |
03:09:16.95 |
+44:54:01.0 |
HIP 14668 |
3.39 |
| 2026-06-12 12:00 |
03:09:21.50 |
+44:54:28.8 |
HIP 14668 |
3.33 |
| 2026-06-13 00:00 |
03:09:26.04 |
+44:54:56.6 |
HIP 14668 |
3.53 |
| 2026-06-13 12:00 |
03:09:30.54 |
+44:55:24.6 |
HIP 14668 |
3.94 |
| 2026-06-14 00:00 |
03:09:35.03 |
+44:55:52.7 |
HIP 14668 |
4.51 |
| 2026-06-14 12:00 |
03:09:39.49 |
+44:56:20.9 |
HIP 14668 |
5.18 |
| 2026-06-15 00:00 |
03:09:43.92 |
+44:56:49.3 |
HIP 14668 |
5.92 |
| 2026-06-15 12:00 |
03:09:48.33 |
+44:57:17.8 |
HIP 14668 |
6.70 |
| 2026-06-16 00:00 |
03:09:52.71 |
+44:57:46.4 |
HIP 14668 |
7.51 |
| 2026-06-16 12:00 |
03:09:57.07 |
+44:58:15.1 |
HIP 14668 |
8.34 |
| 2026-06-17 00:00 |
03:10:01.40 |
+44:58:43.9 |
HIP 14668 |
9.18 |
| 2026-06-17 12:00 |
03:10:05.71 |
+44:59:12.9 |
HIP 14668 |
10.04 |
| 2026-06-18 00:00 |
03:10:09.98 |
+44:59:42.0 |
HIP 14668 |
10.89 |
| 2026-06-18 12:00 |
03:10:14.23 |
+45:00:11.1 |
HIP 14811 |
10.66 |
| 2026-06-19 00:00 |
03:10:18.46 |
+45:00:40.4 |
HIP 14811 |
9.88 |
| 2026-06-19 12:00 |
03:10:22.65 |
+45:01:09.8 |
HIP 14811 |
9.13 |
| 2026-06-20 00:00 |
03:10:26.82 |
+45:01:39.3 |
HIP 14811 |
8.40 |
| 2026-06-20 12:00 |
03:10:30.96 |
+45:02:09.0 |
HIP 14811 |
7.72 |
| 2026-06-21 00:00 |
03:10:35.07 |
+45:02:38.7 |
HIP 14811 |
7.09 |
| 2026-06-21 12:00 |
03:10:39.15 |
+45:03:08.5 |
HIP 14811 |
6.52 |
| 2026-06-22 00:00 |
03:10:43.20 |
+45:03:38.4 |
HIP 14811 |
6.03 |