メタデータ
| 項目 |
値 |
| Designation |
C/2007 K3 (Siding Spring) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2008-04-21T17:04:30.377280Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:31:08Z |
| Obs used |
94 |
| NEO |
- |
| M1 |
13.300 |
| K1 |
13.000 |
| PC |
- |
オスキュレーティング軌道要素
| 項目 |
値 |
| Epoch (epoch_cal, TDB) |
2008-02-09.0000000 |
| e |
1.00124061 |
| q (au) |
2.050740 |
| a (au) |
-1653.004343 |
| i (deg) |
16.300560 |
| Ω (om, deg) |
263.252666 |
| ω (w, deg) |
23.593153 |
| M (ma, deg) |
-0.001066 |
等級
散乱 + 全体線形
$$
M_a = (15.558 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
モデル定数
| 項目 |
値 |
| H0 |
15.558 |
| n |
2.000 |
| gf |
0.992 |
| gb |
-0.528 |
| 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
残差 (区間線形)
$$\epsilon = a \log_{10} r_{\mathrm{au}} + b$$
| 開始日 (UTC) |
終了日 (UTC) |
a |
b |
| 2007-04-18 |
2007-07-18 |
-5.6572 |
+2.028 |
| 2008-06-09 |
2008-09-30 |
+25.5806 |
-9.587 |
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) |
| 2026-03-26 00:00 |
05:07:41.90 |
+23:57:57.6 |
HIP 23900 |
18.82 |
| 2026-03-26 12:00 |
05:07:43.10 |
+23:57:57.5 |
HIP 23900 |
18.74 |
| 2026-03-27 00:00 |
05:07:44.33 |
+23:57:57.4 |
HIP 23900 |
18.66 |
| 2026-03-27 12:00 |
05:07:45.59 |
+23:57:57.3 |
HIP 23900 |
18.59 |
| 2026-03-28 00:00 |
05:07:46.87 |
+23:57:57.3 |
HIP 23900 |
18.51 |
| 2026-03-28 12:00 |
05:07:48.19 |
+23:57:57.3 |
HIP 23900 |
18.44 |
| 2026-03-29 00:00 |
05:07:49.53 |
+23:57:57.4 |
HIP 23900 |
18.37 |
| 2026-03-29 12:00 |
05:07:50.90 |
+23:57:57.5 |
HIP 23900 |
18.31 |
| 2026-03-30 00:00 |
05:07:52.29 |
+23:57:57.6 |
HIP 23900 |
18.25 |
| 2026-03-30 12:00 |
05:07:53.71 |
+23:57:57.7 |
HIP 23900 |
18.19 |
| 2026-03-31 00:00 |
05:07:55.16 |
+23:57:57.9 |
HIP 23900 |
18.14 |
| 2026-03-31 12:00 |
05:07:56.64 |
+23:57:58.2 |
HIP 23900 |
18.09 |
| 2026-04-01 00:00 |
05:07:58.14 |
+23:57:58.4 |
HIP 23900 |
18.04 |
| 2026-04-01 12:00 |
05:07:59.67 |
+23:57:58.8 |
HIP 23900 |
18.00 |
| 2026-04-02 00:00 |
05:08:01.23 |
+23:57:59.1 |
HIP 23900 |
17.97 |
| 2026-04-02 12:00 |
05:08:02.81 |
+23:57:59.5 |
HIP 23900 |
17.94 |
| 2026-04-03 00:00 |
05:08:04.42 |
+23:57:59.9 |
HIP 23900 |
17.92 |
| 2026-04-03 12:00 |
05:08:06.06 |
+23:58:00.3 |
HIP 23900 |
17.91 |
| 2026-04-04 00:00 |
05:08:07.72 |
+23:58:00.8 |
HIP 23900 |
17.90 |
| 2026-04-04 12:00 |
05:08:09.41 |
+23:58:01.3 |
HIP 23900 |
17.90 |
| 2026-04-05 00:00 |
05:08:11.12 |
+23:58:01.9 |
HIP 23900 |
17.91 |
| 2026-04-05 12:00 |
05:08:12.86 |
+23:58:02.5 |
HIP 23900 |
17.93 |
| 2026-04-06 00:00 |
05:08:14.63 |
+23:58:03.1 |
HIP 23900 |
17.95 |
| 2026-04-06 12:00 |
05:08:16.42 |
+23:58:03.8 |
HIP 23900 |
17.99 |
| 2026-04-07 00:00 |
05:08:18.24 |
+23:58:04.5 |
HIP 23900 |
18.03 |
| 2026-04-07 12:00 |
05:08:20.08 |
+23:58:05.2 |
HIP 23900 |
18.09 |
| 2026-04-08 00:00 |
05:08:21.94 |
+23:58:06.0 |
HIP 23900 |
18.15 |
| 2026-04-08 12:00 |
05:08:23.84 |
+23:58:06.8 |
HIP 23900 |
18.23 |
| 2026-04-09 00:00 |
05:08:25.75 |
+23:58:07.6 |
HIP 23900 |
18.31 |
| 2026-04-09 12:00 |
05:08:27.69 |
+23:58:08.4 |
HIP 23900 |
18.41 |
| 2026-04-10 00:00 |
05:08:29.66 |
+23:58:09.3 |
HIP 23900 |
18.52 |
| 2026-04-10 12:00 |
05:08:31.65 |
+23:58:10.3 |
HIP 23900 |
18.64 |
| 2026-04-11 00:00 |
05:08:33.67 |
+23:58:11.2 |
HIP 23900 |
18.77 |
| 2026-04-11 12:00 |
05:08:35.71 |
+23:58:12.2 |
HIP 23900 |
18.91 |
| 2026-04-12 00:00 |
05:08:37.77 |
+23:58:13.3 |
HIP 23900 |
19.06 |
| 2026-04-12 12:00 |
05:08:39.86 |
+23:58:14.3 |
HIP 23900 |
19.23 |
| 2026-04-13 00:00 |
05:08:41.97 |
+23:58:15.4 |
HIP 23900 |
19.41 |
| 2026-04-13 12:00 |
05:08:44.10 |
+23:58:16.5 |
HIP 23900 |
19.60 |
| 2026-04-14 00:00 |
05:08:46.26 |
+23:58:17.7 |
HIP 23900 |
19.80 |
| 2026-04-14 12:00 |
05:08:48.44 |
+23:58:18.9 |
HIP 23900 |
20.02 |
| 2026-04-15 00:00 |
05:08:50.64 |
+23:58:20.1 |
HIP 23900 |
20.24 |
| 2026-04-15 12:00 |
05:08:52.87 |
+23:58:21.3 |
HIP 23900 |
20.48 |
| 2026-04-16 00:00 |
05:08:55.12 |
+23:58:22.6 |
HIP 23900 |
20.73 |