Comet Archive

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C/1999 F1 (Catalina)

メタデータ

項目 値
Designation C/1999 F1 (Catalina)
Type C
Perihelion (tp_cal, UTC) 2002-02-13T15:27:28.321920Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:29:57Z
Obs used 166
NEO -
M1 5.900
K1 7.500
PC 0.030
オスキュレーティング軌道要素
項目 値
Epoch (epoch_cal, TDB) 2001-05-25.0000000
e 0.99912952
q (au) 5.787019
a (au) 6648.103893
i (deg) 92.035388
Ω (om, deg) 20.023133
ω (w, deg) 255.157504
M (ma, deg) 359.999519

等級

C/1999 F1 (Catalina) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (0.773 + 5.058\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目 値
H0 0.773
n 5.058
gf 0.998
gb -0.548
k 1.000
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
1999-03-13 2002-01-17 +0.3101 -0.124
2002-02-15 2005-08-28 -0.2025 -0.528

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 00:08:03.88 +35:10:33.9 HIP 689 15.34
2026-02-03 12:00 00:08:05.86 +35:10:28.1 HIP 689 15.12
2026-02-04 00:00 00:08:07.86 +35:10:22.7 HIP 689 14.91
2026-02-04 12:00 00:08:09.88 +35:10:17.4 HIP 689 14.71
2026-02-05 00:00 00:08:11.92 +35:10:12.4 HIP 689 14.53
2026-02-05 12:00 00:08:13.98 +35:10:07.6 HIP 689 14.36
2026-02-06 00:00 00:08:16.05 +35:10:03.0 HIP 689 14.20
2026-02-06 12:00 00:08:18.15 +35:09:58.7 HIP 689 14.06
2026-02-07 00:00 00:08:20.27 +35:09:54.6 HIP 689 13.94
2026-02-07 12:00 00:08:22.40 +35:09:50.7 HIP 689 13.83
2026-02-08 00:00 00:08:24.55 +35:09:47.1 HIP 689 13.74
2026-02-08 12:00 00:08:26.72 +35:09:43.7 HIP 689 13.66
2026-02-09 00:00 00:08:28.91 +35:09:40.6 HIP 689 13.61
2026-02-09 12:00 00:08:31.12 +35:09:37.6 HIP 689 13.57
2026-02-10 00:00 00:08:33.35 +35:09:35.0 HIP 689 13.55
2026-02-10 12:00 00:08:35.59 +35:09:32.5 HIP 689 13.55
2026-02-11 00:00 00:08:37.85 +35:09:30.3 HIP 689 13.57
2026-02-11 12:00 00:08:40.12 +35:09:28.3 HIP 689 13.61
2026-02-12 00:00 00:08:42.42 +35:09:26.6 HIP 689 13.68
2026-02-12 12:00 00:08:44.73 +35:09:25.1 HIP 689 13.76
2026-02-13 00:00 00:08:47.06 +35:09:23.8 HIP 689 13.86
2026-02-13 12:00 00:08:49.40 +35:09:22.8 HIP 689 13.99
2026-02-14 00:00 00:08:51.76 +35:09:22.0 HIP 689 14.13
2026-02-14 12:00 00:08:54.14 +35:09:21.4 HIP 689 14.29
2026-02-15 00:00 00:08:56.53 +35:09:21.1 HIP 689 14.48
2026-02-15 12:00 00:08:58.94 +35:09:21.0 HIP 689 14.68
2026-02-16 00:00 00:09:01.36 +35:09:21.2 HIP 689 14.90
2026-02-16 12:00 00:09:03.80 +35:09:21.6 HIP 689 15.14
2026-02-17 00:00 00:09:06.26 +35:09:22.2 HIP 689 15.39
2026-02-17 12:00 00:09:08.73 +35:09:23.1 HIP 689 15.67
2026-02-18 00:00 00:09:11.21 +35:09:24.2 HIP 689 15.95
2026-02-18 12:00 00:09:13.71 +35:09:25.5 HIP 689 16.26
2026-02-19 00:00 00:09:16.22 +35:09:27.1 HIP 689 16.58
2026-02-19 12:00 00:09:18.75 +35:09:28.9 HIP 689 16.91
2026-02-20 00:00 00:09:21.29 +35:09:31.0 HIP 689 17.26
2026-02-20 12:00 00:09:23.84 +35:09:33.2 HIP 689 17.62
2026-02-21 00:00 00:09:26.41 +35:09:35.8 HIP 689 18.00
2026-02-21 12:00 00:09:28.99 +35:09:38.5 HIP 689 18.39
2026-02-22 00:00 00:09:31.58 +35:09:41.5 HIP 689 18.78
2026-02-22 12:00 00:09:34.19 +35:09:44.8 HIP 689 19.19
2026-02-23 00:00 00:09:36.81 +35:09:48.2 HIP 689 19.61
2026-02-23 12:00 00:09:39.44 +35:09:51.9 HIP 689 20.04
2026-02-24 00:00 00:09:42.08 +35:09:55.9 HIP 689 20.48