Comet Archive

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C/2004 Q2 (Machholz)

メタデータ

項目
Designation C/2004 Q2 (Machholz)
Type C
Perihelion (tp_cal, UTC) 2005-01-24T21:52:04.915200Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:30:43Z
Obs used 3612
NEO -
M1 11.200
K1 4.500
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2005-03-30.0000000
e 0.99950132
q (au) 1.205042
a (au) 2416.445814
i (deg) 38.588949
Ω (om, deg) 93.622895
ω (w, deg) 19.504703
M (ma, deg) 0.000532

等級

C/2004 Q2 (Machholz) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (4.612 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 4.612
n 6.000
gf 0.800
gb -0.921
k 0.988
δ90 1.000
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
2004-08-28 2005-01-24 -4.3508 +1.375
2005-01-24 2006-09-09 -1.9949 +0.688

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)
2026-02-03 00:00 18:19:22.96 -23:29:18.8 HIP 89741 26.32
2026-02-03 12:00 18:19:25.46 -23:29:18.7 HIP 89741 26.48
2026-02-04 00:00 18:19:27.93 -23:29:18.6 HIP 89741 26.65
2026-02-04 12:00 18:19:30.39 -23:29:18.5 HIP 89741 26.83
2026-02-05 00:00 18:19:32.83 -23:29:18.5 HIP 89741 27.02
2026-02-05 12:00 18:19:35.25 -23:29:18.4 HIP 89741 27.22
2026-02-06 00:00 18:19:37.65 -23:29:18.3 HIP 89741 27.42
2026-02-06 12:00 18:19:40.04 -23:29:18.2 HIP 89741 27.64
2026-02-07 00:00 18:19:42.41 -23:29:18.2 HIP 89741 27.86
2026-02-07 12:00 18:19:44.76 -23:29:18.1 HIP 89741 28.09
2026-02-08 00:00 18:19:47.10 -23:29:18.1 HIP 89741 28.32
2026-02-08 12:00 18:19:49.41 -23:29:18.1 HIP 89741 28.57
2026-02-09 00:00 18:19:51.71 -23:29:18.0 HIP 89741 28.81
2026-02-09 12:00 18:19:53.99 -23:29:18.0 HIP 89741 29.07
2026-02-10 00:00 18:19:56.24 -23:29:18.0 HIP 89741 29.32
2026-02-10 12:00 18:19:58.48 -23:29:18.0 HIP 89741 29.59
2026-02-11 00:00 18:20:00.71 -23:29:18.0 HIP 89915 29.69
2026-02-11 12:00 18:20:02.91 -23:29:18.0 HIP 89915 29.49
2026-02-12 00:00 18:20:05.09 -23:29:18.0 HIP 89915 29.31
2026-02-12 12:00 18:20:07.25 -23:29:18.1 HIP 89915 29.13
2026-02-13 00:00 18:20:09.39 -23:29:18.1 HIP 89915 28.96
2026-02-13 12:00 18:20:11.52 -23:29:18.2 HIP 89915 28.80
2026-02-14 00:00 18:20:13.62 -23:29:18.2 HIP 89915 28.65
2026-02-14 12:00 18:20:15.70 -23:29:18.3 HIP 89915 28.51
2026-02-15 00:00 18:20:17.76 -23:29:18.3 HIP 89915 28.37
2026-02-15 12:00 18:20:19.80 -23:29:18.4 HIP 89915 28.24
2026-02-16 00:00 18:20:21.82 -23:29:18.5 HIP 89915 28.13
2026-02-16 12:00 18:20:23.82 -23:29:18.6 HIP 89915 28.02
2026-02-17 00:00 18:20:25.80 -23:29:18.7 HIP 89915 27.91
2026-02-17 12:00 18:20:27.75 -23:29:18.8 HIP 89915 27.82
2026-02-18 00:00 18:20:29.69 -23:29:19.0 HIP 89915 27.73
2026-02-18 12:00 18:20:31.60 -23:29:19.1 HIP 89915 27.65
2026-02-19 00:00 18:20:33.49 -23:29:19.2 HIP 89915 27.58
2026-02-19 12:00 18:20:35.36 -23:29:19.4 HIP 89915 27.52
2026-02-20 00:00 18:20:37.21 -23:29:19.6 HIP 89915 27.46
2026-02-20 12:00 18:20:39.03 -23:29:19.8 HIP 89915 27.41
2026-02-21 00:00 18:20:40.84 -23:29:19.9 HIP 89915 27.36
2026-02-21 12:00 18:20:42.62 -23:29:20.1 HIP 89915 27.33
2026-02-22 00:00 18:20:44.37 -23:29:20.4 HIP 89915 27.29
2026-02-22 12:00 18:20:46.11 -23:29:20.6 HIP 89915 27.27
2026-02-23 00:00 18:20:47.82 -23:29:20.8 HIP 89915 27.25
2026-02-23 12:00 18:20:49.51 -23:29:21.0 HIP 89915 27.23
2026-02-24 00:00 18:20:51.18 -23:29:21.3 HIP 89915 27.23