メタデータ
| 項目 |
値 |
| Designation |
C/2012 OP (Siding Spring) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2012-12-04T17:50:22.822080Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:32:19Z |
| Obs used |
100 |
| NEO |
- |
| M1 |
14.400 |
| 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) |
2013-01-23.0000000 |
| e |
0.99657940 |
| q (au) |
3.607071 |
| a (au) |
1054.514944 |
| i (deg) |
114.828786 |
| Ω (om, deg) |
267.370339 |
| ω (w, deg) |
351.435364 |
| M (ma, deg) |
0.001418 |
等級
散乱 + 全体線形
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| 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 |
08:31:18.26 |
+63:31:02.1 |
HIP 42045 |
20.36 |
| 2026-06-01 12:00 |
08:31:22.56 |
+63:30:18.2 |
HIP 42045 |
20.16 |
| 2026-06-02 00:00 |
08:31:26.91 |
+63:29:34.3 |
HIP 42045 |
19.98 |
| 2026-06-02 12:00 |
08:31:31.32 |
+63:28:50.6 |
HIP 42045 |
19.83 |
| 2026-06-03 00:00 |
08:31:35.78 |
+63:28:07.1 |
HIP 42045 |
19.72 |
| 2026-06-03 12:00 |
08:31:40.30 |
+63:27:23.7 |
HIP 42045 |
19.64 |
| 2026-06-04 00:00 |
08:31:44.87 |
+63:26:40.5 |
HIP 42045 |
19.59 |
| 2026-06-04 12:00 |
08:31:49.49 |
+63:25:57.4 |
HIP 42045 |
19.57 |
| 2026-06-05 00:00 |
08:31:54.16 |
+63:25:14.5 |
HIP 42045 |
19.59 |
| 2026-06-05 12:00 |
08:31:58.89 |
+63:24:31.7 |
HIP 42045 |
19.64 |
| 2026-06-06 00:00 |
08:32:03.66 |
+63:23:49.1 |
HIP 42045 |
19.72 |
| 2026-06-06 12:00 |
08:32:08.49 |
+63:23:06.6 |
HIP 42045 |
19.84 |
| 2026-06-07 00:00 |
08:32:13.37 |
+63:22:24.3 |
HIP 42045 |
19.98 |
| 2026-06-07 12:00 |
08:32:18.30 |
+63:21:42.2 |
HIP 42091 |
19.70 |
| 2026-06-08 00:00 |
08:32:23.27 |
+63:21:00.3 |
HIP 42091 |
18.85 |
| 2026-06-08 12:00 |
08:32:28.30 |
+63:20:18.5 |
HIP 42091 |
18.00 |
| 2026-06-09 00:00 |
08:32:33.38 |
+63:19:36.9 |
HIP 42091 |
17.15 |
| 2026-06-09 12:00 |
08:32:38.50 |
+63:18:55.5 |
HIP 42091 |
16.31 |
| 2026-06-10 00:00 |
08:32:43.67 |
+63:18:14.2 |
HIP 42091 |
15.46 |
| 2026-06-10 12:00 |
08:32:48.89 |
+63:17:33.2 |
HIP 42091 |
14.62 |
| 2026-06-11 00:00 |
08:32:54.16 |
+63:16:52.3 |
HIP 42091 |
13.79 |
| 2026-06-11 12:00 |
08:32:59.47 |
+63:16:11.6 |
HIP 42091 |
12.96 |
| 2026-06-12 00:00 |
08:33:04.83 |
+63:15:31.0 |
HIP 42091 |
12.13 |
| 2026-06-12 12:00 |
08:33:10.24 |
+63:14:50.7 |
HIP 42091 |
11.32 |
| 2026-06-13 00:00 |
08:33:15.69 |
+63:14:10.6 |
HIP 42091 |
10.51 |
| 2026-06-13 12:00 |
08:33:21.19 |
+63:13:30.6 |
HIP 42091 |
9.72 |
| 2026-06-14 00:00 |
08:33:26.73 |
+63:12:50.9 |
HIP 42091 |
8.95 |
| 2026-06-14 12:00 |
08:33:32.31 |
+63:12:11.3 |
HIP 42091 |
8.20 |
| 2026-06-15 00:00 |
08:33:37.94 |
+63:11:32.0 |
HIP 42091 |
7.48 |
| 2026-06-15 12:00 |
08:33:43.61 |
+63:10:52.8 |
HIP 42091 |
6.81 |
| 2026-06-16 00:00 |
08:33:49.33 |
+63:10:13.9 |
HIP 42091 |
6.18 |
| 2026-06-16 12:00 |
08:33:55.08 |
+63:09:35.1 |
HIP 42091 |
5.64 |
| 2026-06-17 00:00 |
08:34:00.88 |
+63:08:56.6 |
HIP 42091 |
5.19 |
| 2026-06-17 12:00 |
08:34:06.72 |
+63:08:18.3 |
HIP 42091 |
4.87 |
| 2026-06-18 00:00 |
08:34:12.60 |
+63:07:40.1 |
HIP 42091 |
4.70 |
| 2026-06-18 12:00 |
08:34:18.52 |
+63:07:02.2 |
HIP 42091 |
4.70 |
| 2026-06-19 00:00 |
08:34:24.47 |
+63:06:24.6 |
HIP 42091 |
4.88 |
| 2026-06-19 12:00 |
08:34:30.47 |
+63:05:47.1 |
HIP 42091 |
5.21 |
| 2026-06-20 00:00 |
08:34:36.50 |
+63:05:09.8 |
HIP 42091 |
5.66 |
| 2026-06-20 12:00 |
08:34:42.58 |
+63:04:32.8 |
HIP 42091 |
6.22 |
| 2026-06-21 00:00 |
08:34:48.69 |
+63:03:56.0 |
HIP 42091 |
6.85 |
| 2026-06-21 12:00 |
08:34:54.83 |
+63:03:19.4 |
HIP 42091 |
7.54 |
| 2026-06-22 00:00 |
08:35:01.02 |
+63:02:43.1 |
HIP 42091 |
8.27 |