メタデータ
| 項目 |
値 |
| Designation |
C/2007 Q3 (Siding Spring) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2009-10-07T06:29:51.262080Z |
| Orbit solution date (soln_date, UTC) |
2025-07-07T14:12:19Z |
| Obs used |
1341 |
| NEO |
- |
| M1 |
8.800 |
| K1 |
5.500 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2009-08-20.0000000 |
| e |
1.00023766 |
| q (au) |
2.251688 |
| a (au) |
-9474.438449 |
| i (deg) |
65.650492 |
| Ω (om, deg) |
149.412684 |
| ω (w, deg) |
2.092860 |
| M (ma, deg) |
-0.000052 |
等級
散乱 + 全体線形
$$
M_a = (7.715 + 2.602\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
7.715 |
| n |
2.602 |
| gf |
0.999 |
| gb |
-0.644 |
| k |
0.990 |
| 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 |
| 2007-08-25 |
2009-03-15 |
+1.0261 |
-1.390 |
| 2009-03-15 |
2009-05-10 |
+22.4756 |
-12.601 |
| 2009-05-10 |
2009-10-03 |
-25.2024 |
+8.557 |
| 2009-10-10 |
2010-02-28 |
+8.7989 |
-3.980 |
| 2010-02-28 |
2010-06-04 |
+2.9606 |
-2.284 |
| 2010-06-04 |
2010-10-30 |
+3.8990 |
-2.293 |
| 2010-10-30 |
2011-09-25 |
+6.2804 |
-3.627 |
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) |
| 2026-09-20 00:00 |
20:45:04.12 |
+08:09:25.6 |
HIP 102472 |
13.97 |
| 2026-09-20 12:00 |
20:45:02.09 |
+08:08:58.2 |
HIP 102472 |
14.61 |
| 2026-09-21 00:00 |
20:45:00.08 |
+08:08:30.8 |
HIP 102472 |
15.25 |
| 2026-09-21 12:00 |
20:44:58.09 |
+08:08:03.3 |
HIP 102472 |
15.90 |
| 2026-09-22 00:00 |
20:44:56.13 |
+08:07:35.7 |
HIP 102472 |
16.53 |
| 2026-09-22 12:00 |
20:44:54.19 |
+08:07:08.2 |
HIP 102472 |
17.17 |
| 2026-09-23 00:00 |
20:44:52.27 |
+08:06:40.6 |
HIP 102472 |
17.80 |
| 2026-09-23 12:00 |
20:44:50.38 |
+08:06:13.0 |
HIP 102472 |
18.43 |
| 2026-09-24 00:00 |
20:44:48.51 |
+08:05:45.3 |
HIP 102472 |
19.06 |
| 2026-09-24 12:00 |
20:44:46.66 |
+08:05:17.6 |
HIP 102472 |
19.69 |
| 2026-09-25 00:00 |
20:44:44.83 |
+08:04:49.9 |
HIP 102472 |
20.31 |
| 2026-09-25 12:00 |
20:44:43.03 |
+08:04:22.2 |
HIP 102472 |
20.92 |
| 2026-09-26 00:00 |
20:44:41.25 |
+08:03:54.5 |
HIP 102472 |
21.54 |
| 2026-09-26 12:00 |
20:44:39.50 |
+08:03:26.7 |
HIP 102472 |
22.15 |
| 2026-09-27 00:00 |
20:44:37.77 |
+08:02:58.9 |
HIP 102472 |
22.76 |
| 2026-09-27 12:00 |
20:44:36.07 |
+08:02:31.1 |
HIP 102472 |
23.36 |
| 2026-09-28 00:00 |
20:44:34.39 |
+08:02:03.3 |
HIP 102472 |
23.96 |
| 2026-09-28 12:00 |
20:44:32.73 |
+08:01:35.5 |
HIP 102472 |
24.56 |
| 2026-09-29 00:00 |
20:44:31.10 |
+08:01:07.6 |
HIP 102472 |
25.15 |
| 2026-09-29 12:00 |
20:44:29.49 |
+08:00:39.8 |
HIP 102472 |
25.74 |
| 2026-09-30 00:00 |
20:44:27.91 |
+08:00:12.0 |
HIP 102472 |
26.32 |
| 2026-09-30 12:00 |
20:44:26.35 |
+07:59:44.1 |
HIP 102472 |
26.90 |
| 2026-10-01 00:00 |
20:44:24.82 |
+07:59:16.3 |
HIP 102472 |
27.48 |
| 2026-10-01 12:00 |
20:44:23.31 |
+07:58:48.4 |
HIP 102472 |
28.05 |
| 2026-10-02 00:00 |
20:44:21.83 |
+07:58:20.6 |
HIP 102472 |
28.62 |
| 2026-10-02 12:00 |
20:44:20.37 |
+07:57:52.7 |
HIP 102472 |
29.18 |
| 2026-10-03 00:00 |
20:44:18.94 |
+07:57:24.9 |
HIP 102472 |
29.74 |
| 2026-10-03 12:00 |
20:44:17.54 |
+07:56:57.0 |
HIP 102472 |
30.30 |
| 2026-10-04 00:00 |
20:44:16.16 |
+07:56:29.2 |
HIP 102472 |
30.85 |
| 2026-10-04 12:00 |
20:44:14.80 |
+07:56:01.4 |
HIP 102472 |
31.39 |
| 2026-10-05 00:00 |
20:44:13.47 |
+07:55:33.6 |
HIP 102472 |
31.94 |
| 2026-10-05 12:00 |
20:44:12.17 |
+07:55:05.8 |
HIP 102472 |
32.47 |
| 2026-10-06 00:00 |
20:44:10.90 |
+07:54:38.0 |
HIP 102472 |
33.01 |
| 2026-10-06 12:00 |
20:44:09.65 |
+07:54:10.3 |
HIP 102472 |
33.54 |
| 2026-10-07 00:00 |
20:44:08.43 |
+07:53:42.6 |
HIP 102472 |
34.06 |
| 2026-10-07 12:00 |
20:44:07.23 |
+07:53:14.9 |
HIP 102472 |
34.58 |
| 2026-10-08 00:00 |
20:44:06.06 |
+07:52:47.2 |
HIP 102472 |
35.10 |
| 2026-10-08 12:00 |
20:44:04.92 |
+07:52:19.5 |
HIP 102472 |
35.61 |
| 2026-10-09 00:00 |
20:44:03.81 |
+07:51:51.9 |
HIP 102472 |
36.11 |
| 2026-10-09 12:00 |
20:44:02.72 |
+07:51:24.3 |
HIP 102472 |
36.62 |
| 2026-10-10 00:00 |
20:44:01.66 |
+07:50:56.8 |
HIP 102472 |
37.11 |
| 2026-10-10 12:00 |
20:44:00.63 |
+07:50:29.3 |
HIP 102472 |
37.61 |
| 2026-10-11 00:00 |
20:43:59.62 |
+07:50:01.8 |
HIP 102472 |
38.09 |