C/2007 Q3 (Siding Spring)

メタデータ

項目
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
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

C/2007 Q3 (Siding Spring) · Magnitude (Full range)

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
H0 7.715
n 2.602
gf 1.000
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)
2026-03-26 00:00 20:54:11.53 +08:05:22.7 HIP 103185 6.15
2026-03-26 12:00 20:54:13.64 +08:05:45.6 HIP 103185 5.62
2026-03-27 00:00 20:54:15.72 +08:06:08.5 HIP 103185 5.12
2026-03-27 12:00 20:54:17.78 +08:06:31.5 HIP 103185 4.65
2026-03-28 00:00 20:54:19.82 +08:06:54.5 HIP 103185 4.23
2026-03-28 12:00 20:54:21.83 +08:07:17.5 HIP 103185 3.87
2026-03-29 00:00 20:54:23.82 +08:07:40.5 HIP 103185 3.57
2026-03-29 12:00 20:54:25.79 +08:08:03.5 HIP 103185 3.37
2026-03-30 00:00 20:54:27.73 +08:08:26.5 HIP 103185 3.27
2026-03-30 12:00 20:54:29.65 +08:08:49.6 HIP 103185 3.28
2026-03-31 00:00 20:54:31.55 +08:09:12.6 HIP 103185 3.40
2026-03-31 12:00 20:54:33.43 +08:09:35.7 HIP 103185 3.61
2026-04-01 00:00 20:54:35.27 +08:09:58.8 HIP 103185 3.89
2026-04-01 12:00 20:54:37.10 +08:10:21.9 HIP 103185 4.24
2026-04-02 00:00 20:54:38.90 +08:10:45.0 HIP 103185 4.63
2026-04-02 12:00 20:54:40.68 +08:11:08.0 HIP 103185 5.05
2026-04-03 00:00 20:54:42.43 +08:11:31.1 HIP 103185 5.50
2026-04-03 12:00 20:54:44.16 +08:11:54.2 HIP 103185 5.96
2026-04-04 00:00 20:54:45.86 +08:12:17.3 HIP 103185 6.44
2026-04-04 12:00 20:54:47.54 +08:12:40.4 HIP 103185 6.92
2026-04-05 00:00 20:54:49.20 +08:13:03.5 HIP 103185 7.41
2026-04-05 12:00 20:54:50.83 +08:13:26.6 HIP 103185 7.91
2026-04-06 00:00 20:54:52.43 +08:13:49.6 HIP 103185 8.40
2026-04-06 12:00 20:54:54.01 +08:14:12.7 HIP 103185 8.90
2026-04-07 00:00 20:54:55.57 +08:14:35.8 HIP 103185 9.40
2026-04-07 12:00 20:54:57.10 +08:14:58.8 HIP 103185 9.89
2026-04-08 00:00 20:54:58.60 +08:15:21.8 HIP 103185 10.39
2026-04-08 12:00 20:55:00.08 +08:15:44.8 HIP 103185 10.88
2026-04-09 00:00 20:55:01.54 +08:16:07.8 HIP 103185 11.37
2026-04-09 12:00 20:55:02.96 +08:16:30.7 HIP 103185 11.85
2026-04-10 00:00 20:55:04.37 +08:16:53.7 HIP 103185 12.34
2026-04-10 12:00 20:55:05.74 +08:17:16.6 HIP 103185 12.82
2026-04-11 00:00 20:55:07.09 +08:17:39.5 HIP 103185 13.30
2026-04-11 12:00 20:55:08.42 +08:18:02.4 HIP 103185 13.77
2026-04-12 00:00 20:55:09.71 +08:18:25.2 HIP 103185 14.24
2026-04-12 12:00 20:55:10.98 +08:18:48.0 HIP 103185 14.70
2026-04-13 00:00 20:55:12.23 +08:19:10.8 HIP 103185 15.17
2026-04-13 12:00 20:55:13.45 +08:19:33.5 HIP 103185 15.62
2026-04-14 00:00 20:55:14.64 +08:19:56.2 HIP 103185 16.08
2026-04-14 12:00 20:55:15.81 +08:20:18.8 HIP 103185 16.52
2026-04-15 00:00 20:55:16.94 +08:20:41.4 HIP 103185 16.97
2026-04-15 12:00 20:55:18.06 +08:21:04.0 HIP 103185 17.41
2026-04-16 00:00 20:55:19.14 +08:21:26.6 HIP 103185 17.84