メタデータ
| 項目 |
値 |
| Designation |
C/2012 H2 (McNaught) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2012-05-03T17:33:48.790080Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:07Z |
| Obs used |
40 |
| NEO |
- |
| M1 |
15.700 |
| K1 |
10.000 |
| PC |
0.030 |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2012-05-18.0000000 |
| e |
0.89360944 |
| q (au) |
1.716772 |
| a (au) |
16.136509 |
| i (deg) |
92.835585 |
| Ω (om, deg) |
184.135948 |
| ω (w, deg) |
295.901982 |
| M (ma, deg) |
0.216949 |
等級
散乱 + 全体線形
$$
M_a = (15.847 + 4.598\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
15.847 |
| n |
4.598 |
| gf |
1.000 |
| gb |
-0.576 |
| k |
0.800 |
| 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) |
| 2026-03-26 00:00 |
20:16:45.02 |
+66:42:32.4 |
HIP 100017 |
9.74 |
| 2026-03-26 12:00 |
20:16:51.52 |
+66:43:36.7 |
HIP 100017 |
8.49 |
| 2026-03-27 00:00 |
20:16:57.94 |
+66:44:41.2 |
HIP 100017 |
7.25 |
| 2026-03-27 12:00 |
20:17:04.26 |
+66:45:45.9 |
HIP 100017 |
6.00 |
| 2026-03-28 00:00 |
20:17:10.51 |
+66:46:50.9 |
HIP 100017 |
4.76 |
| 2026-03-28 12:00 |
20:17:16.66 |
+66:47:56.1 |
HIP 100017 |
3.52 |
| 2026-03-29 00:00 |
20:17:22.72 |
+66:49:01.6 |
HIP 100017 |
2.29 |
| 2026-03-29 12:00 |
20:17:28.70 |
+66:50:07.3 |
HIP 100017 |
1.07 |
| 2026-03-30 00:00 |
20:17:34.58 |
+66:51:13.2 |
HIP 100017 |
0.39 |
| 2026-03-30 12:00 |
20:17:40.38 |
+66:52:19.3 |
HIP 100017 |
1.49 |
| 2026-03-31 00:00 |
20:17:46.09 |
+66:53:25.6 |
HIP 100017 |
2.71 |
| 2026-03-31 12:00 |
20:17:51.70 |
+66:54:32.2 |
HIP 100017 |
3.94 |
| 2026-04-01 00:00 |
20:17:57.23 |
+66:55:39.0 |
HIP 100017 |
5.18 |
| 2026-04-01 12:00 |
20:18:02.67 |
+66:56:45.9 |
HIP 100017 |
6.41 |
| 2026-04-02 00:00 |
20:18:08.01 |
+66:57:53.1 |
HIP 100017 |
7.64 |
| 2026-04-02 12:00 |
20:18:13.26 |
+66:59:00.5 |
HIP 100017 |
8.87 |
| 2026-04-03 00:00 |
20:18:18.42 |
+67:00:08.0 |
HIP 100017 |
10.11 |
| 2026-04-03 12:00 |
20:18:23.48 |
+67:01:15.8 |
HIP 100017 |
11.34 |
| 2026-04-04 00:00 |
20:18:28.46 |
+67:02:23.7 |
HIP 100017 |
12.56 |
| 2026-04-04 12:00 |
20:18:33.34 |
+67:03:31.8 |
HIP 100017 |
13.79 |
| 2026-04-05 00:00 |
20:18:38.12 |
+67:04:40.1 |
HIP 100017 |
15.02 |
| 2026-04-05 12:00 |
20:18:42.81 |
+67:05:48.5 |
HIP 100017 |
16.24 |
| 2026-04-06 00:00 |
20:18:47.41 |
+67:06:57.1 |
HIP 100017 |
17.47 |
| 2026-04-06 12:00 |
20:18:51.91 |
+67:08:05.9 |
HIP 100017 |
18.69 |
| 2026-04-07 00:00 |
20:18:56.31 |
+67:09:14.8 |
HIP 100017 |
19.91 |
| 2026-04-07 12:00 |
20:19:00.62 |
+67:10:23.9 |
HIP 100017 |
21.13 |
| 2026-04-08 00:00 |
20:19:04.83 |
+67:11:33.1 |
HIP 100017 |
22.35 |
| 2026-04-08 12:00 |
20:19:08.94 |
+67:12:42.5 |
HIP 100017 |
23.57 |
| 2026-04-09 00:00 |
20:19:12.96 |
+67:13:52.0 |
HIP 100017 |
24.79 |
| 2026-04-09 12:00 |
20:19:16.88 |
+67:15:01.7 |
HIP 100017 |
26.00 |
| 2026-04-10 00:00 |
20:19:20.69 |
+67:16:11.4 |
HIP 100017 |
27.21 |
| 2026-04-10 12:00 |
20:19:24.42 |
+67:17:21.3 |
HIP 100017 |
28.43 |
| 2026-04-11 00:00 |
20:19:28.04 |
+67:18:31.4 |
HIP 100017 |
29.64 |
| 2026-04-11 12:00 |
20:19:31.56 |
+67:19:41.5 |
HIP 100017 |
30.85 |
| 2026-04-12 00:00 |
20:19:34.98 |
+67:20:51.7 |
HIP 100017 |
32.05 |
| 2026-04-12 12:00 |
20:19:38.30 |
+67:22:02.1 |
HIP 100017 |
33.26 |
| 2026-04-13 00:00 |
20:19:41.52 |
+67:23:12.5 |
HIP 100017 |
34.46 |
| 2026-04-13 12:00 |
20:19:44.64 |
+67:24:23.1 |
HIP 99791 |
35.51 |
| 2026-04-14 00:00 |
20:19:47.65 |
+67:25:33.7 |
HIP 99791 |
35.03 |
| 2026-04-14 12:00 |
20:19:50.57 |
+67:26:44.4 |
HIP 99791 |
34.58 |
| 2026-04-15 00:00 |
20:19:53.38 |
+67:27:55.2 |
HIP 99791 |
34.15 |
| 2026-04-15 12:00 |
20:19:56.09 |
+67:29:06.1 |
HIP 99791 |
33.75 |
| 2026-04-16 00:00 |
20:19:58.69 |
+67:30:17.0 |
HIP 99791 |
33.39 |