メタデータ
| 項目 |
値 |
| Designation |
C/2013 G2 (McNaught) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2012-12-06T08:24:02.825280Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:32Z |
| Obs used |
111 |
| NEO |
- |
| M1 |
13.700 |
| 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) |
2013-05-24.0000000 |
| e |
1.00017667 |
| q (au) |
2.154122 |
| a (au) |
-12193.190355 |
| i (deg) |
96.001965 |
| Ω (om, deg) |
274.112530 |
| ω (w, deg) |
293.912193 |
| M (ma, deg) |
0.000123 |
等級
散乱 + 全体線形
$$
M_a = (11.810 + 2.787\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
11.810 |
| n |
2.787 |
| gf |
1.000 |
| gb |
-0.500 |
| k |
1.000 |
| 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
天体暦
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-06-01 00:00 |
17:21:32.63 |
+60:21:00.9 |
HIP 85144 |
28.93 |
| 2026-06-01 12:00 |
17:21:24.72 |
+60:21:16.3 |
HIP 85144 |
29.35 |
| 2026-06-02 00:00 |
17:21:16.80 |
+60:21:31.2 |
HIP 85144 |
29.81 |
| 2026-06-02 12:00 |
17:21:08.86 |
+60:21:45.6 |
HIP 85144 |
30.30 |
| 2026-06-03 00:00 |
17:21:00.91 |
+60:21:59.4 |
HIP 85144 |
30.82 |
| 2026-06-03 12:00 |
17:20:52.96 |
+60:22:12.8 |
HIP 85144 |
31.37 |
| 2026-06-04 00:00 |
17:20:44.99 |
+60:22:25.6 |
HIP 85144 |
31.95 |
| 2026-06-04 12:00 |
17:20:37.01 |
+60:22:37.9 |
HIP 85144 |
32.56 |
| 2026-06-05 00:00 |
17:20:29.02 |
+60:22:49.6 |
HIP 85144 |
33.20 |
| 2026-06-05 12:00 |
17:20:21.03 |
+60:23:00.9 |
HIP 84496 |
33.28 |
| 2026-06-06 00:00 |
17:20:13.02 |
+60:23:11.6 |
HIP 84496 |
32.35 |
| 2026-06-06 12:00 |
17:20:05.01 |
+60:23:21.8 |
HIP 84496 |
31.42 |
| 2026-06-07 00:00 |
17:19:56.99 |
+60:23:31.5 |
HIP 84496 |
30.51 |
| 2026-06-07 12:00 |
17:19:48.97 |
+60:23:40.7 |
HIP 84496 |
29.60 |
| 2026-06-08 00:00 |
17:19:40.94 |
+60:23:49.3 |
HIP 84496 |
28.70 |
| 2026-06-08 12:00 |
17:19:32.91 |
+60:23:57.4 |
HIP 84496 |
27.82 |
| 2026-06-09 00:00 |
17:19:24.87 |
+60:24:05.0 |
HIP 84496 |
26.95 |
| 2026-06-09 12:00 |
17:19:16.83 |
+60:24:12.1 |
HIP 84496 |
26.09 |
| 2026-06-10 00:00 |
17:19:08.79 |
+60:24:18.6 |
HIP 84496 |
25.25 |
| 2026-06-10 12:00 |
17:19:00.74 |
+60:24:24.6 |
HIP 84496 |
24.42 |
| 2026-06-11 00:00 |
17:18:52.70 |
+60:24:30.1 |
HIP 84496 |
23.62 |
| 2026-06-11 12:00 |
17:18:44.65 |
+60:24:35.0 |
HIP 84496 |
22.83 |
| 2026-06-12 00:00 |
17:18:36.60 |
+60:24:39.5 |
HIP 84496 |
22.07 |
| 2026-06-12 12:00 |
17:18:28.56 |
+60:24:43.4 |
HIP 84496 |
21.33 |
| 2026-06-13 00:00 |
17:18:20.51 |
+60:24:46.7 |
HIP 84496 |
20.62 |
| 2026-06-13 12:00 |
17:18:12.47 |
+60:24:49.6 |
HIP 84496 |
19.95 |
| 2026-06-14 00:00 |
17:18:04.43 |
+60:24:51.9 |
HIP 84496 |
19.30 |
| 2026-06-14 12:00 |
17:17:56.40 |
+60:24:53.7 |
HIP 84496 |
18.70 |
| 2026-06-15 00:00 |
17:17:48.37 |
+60:24:54.9 |
HIP 84496 |
18.13 |
| 2026-06-15 12:00 |
17:17:40.34 |
+60:24:55.7 |
HIP 84496 |
17.61 |
| 2026-06-16 00:00 |
17:17:32.32 |
+60:24:55.9 |
HIP 84496 |
17.15 |
| 2026-06-16 12:00 |
17:17:24.31 |
+60:24:55.5 |
HIP 84496 |
16.73 |
| 2026-06-17 00:00 |
17:17:16.30 |
+60:24:54.7 |
HIP 84496 |
16.37 |
| 2026-06-17 12:00 |
17:17:08.31 |
+60:24:53.3 |
HIP 84496 |
16.07 |
| 2026-06-18 00:00 |
17:17:00.32 |
+60:24:51.4 |
HIP 84496 |
15.84 |
| 2026-06-18 12:00 |
17:16:52.34 |
+60:24:49.0 |
HIP 84496 |
15.67 |
| 2026-06-19 00:00 |
17:16:44.37 |
+60:24:46.1 |
HIP 84496 |
15.58 |
| 2026-06-19 12:00 |
17:16:36.41 |
+60:24:42.6 |
HIP 84496 |
15.55 |
| 2026-06-20 00:00 |
17:16:28.46 |
+60:24:38.7 |
HIP 84496 |
15.59 |
| 2026-06-20 12:00 |
17:16:20.53 |
+60:24:34.2 |
HIP 84496 |
15.70 |
| 2026-06-21 00:00 |
17:16:12.61 |
+60:24:29.2 |
HIP 84496 |
15.88 |
| 2026-06-21 12:00 |
17:16:04.70 |
+60:24:23.6 |
HIP 84496 |
16.13 |
| 2026-06-22 00:00 |
17:15:56.81 |
+60:24:17.6 |
HIP 84496 |
16.44 |