Comet Archive

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C/2004 X2 (LINEAR)

メタデータ

項目
Designation C/2004 X2 (LINEAR)
Type C
Perihelion (tp_cal, UTC) 2004-08-24T08:00:06.079680Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:30:45Z
Obs used 252
NEO -
M1 12.900
K1 4.500
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2005-01-15.0000000
e 0.99737720
q (au) 3.793087
a (au) 1446.194953
i (deg) 72.117890
Ω (om, deg) 307.341187
ω (w, deg) 162.215319
M (ma, deg) 0.002575

等級

C/2004 X2 (LINEAR) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (15.808 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 15.808
n 2.000
gf 0.998
gb -0.783
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

天体暦

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-02-03 00:00 20:10:48.08 -70:35:18.7 HIP 99776 19.36
2026-02-03 12:00 20:10:56.68 -70:35:17.7 HIP 99776 18.67
2026-02-04 00:00 20:11:05.27 -70:35:17.0 HIP 99776 17.98
2026-02-04 12:00 20:11:13.83 -70:35:16.5 HIP 99776 17.30
2026-02-05 00:00 20:11:22.38 -70:35:16.4 HIP 99776 16.61
2026-02-05 12:00 20:11:30.91 -70:35:16.5 HIP 99776 15.93
2026-02-06 00:00 20:11:39.42 -70:35:16.9 HIP 99776 15.25
2026-02-06 12:00 20:11:47.91 -70:35:17.6 HIP 99776 14.58
2026-02-07 00:00 20:11:56.38 -70:35:18.5 HIP 99776 13.91
2026-02-07 12:00 20:12:04.82 -70:35:19.8 HIP 99776 13.24
2026-02-08 00:00 20:12:13.25 -70:35:21.3 HIP 99776 12.58
2026-02-08 12:00 20:12:21.65 -70:35:23.1 HIP 99776 11.91
2026-02-09 00:00 20:12:30.03 -70:35:25.2 HIP 99776 11.26
2026-02-09 12:00 20:12:38.39 -70:35:27.5 HIP 99776 10.61
2026-02-10 00:00 20:12:46.72 -70:35:30.1 HIP 99776 9.96
2026-02-10 12:00 20:12:55.03 -70:35:33.1 HIP 99776 9.32
2026-02-11 00:00 20:13:03.31 -70:35:36.2 HIP 99776 8.69
2026-02-11 12:00 20:13:11.57 -70:35:39.7 HIP 99776 8.06
2026-02-12 00:00 20:13:19.80 -70:35:43.4 HIP 99776 7.45
2026-02-12 12:00 20:13:28.00 -70:35:47.5 HIP 99776 6.85
2026-02-13 00:00 20:13:36.18 -70:35:51.8 HIP 99776 6.27
2026-02-13 12:00 20:13:44.33 -70:35:56.3 HIP 99776 5.70
2026-02-14 00:00 20:13:52.46 -70:36:01.2 HIP 99776 5.17
2026-02-14 12:00 20:14:00.55 -70:36:06.3 HIP 99776 4.67
2026-02-15 00:00 20:14:08.61 -70:36:11.7 HIP 99776 4.21
2026-02-15 12:00 20:14:16.65 -70:36:17.4 HIP 99776 3.82
2026-02-16 00:00 20:14:24.65 -70:36:23.4 HIP 99776 3.50
2026-02-16 12:00 20:14:32.63 -70:36:29.6 HIP 99776 3.30
2026-02-17 00:00 20:14:40.57 -70:36:36.1 HIP 99776 3.21
2026-02-17 12:00 20:14:48.48 -70:36:42.9 HIP 99776 3.26
2026-02-18 00:00 20:14:56.36 -70:36:49.9 HIP 99776 3.43
2026-02-18 12:00 20:15:04.20 -70:36:57.2 HIP 99776 3.71
2026-02-19 00:00 20:15:12.01 -70:37:04.8 HIP 99776 4.08
2026-02-19 12:00 20:15:19.79 -70:37:12.7 HIP 99776 4.50
2026-02-20 00:00 20:15:27.53 -70:37:20.9 HIP 99776 4.98
2026-02-20 12:00 20:15:35.24 -70:37:29.3 HIP 99776 5.48
2026-02-21 00:00 20:15:42.91 -70:37:38.0 HIP 99776 6.01
2026-02-21 12:00 20:15:50.55 -70:37:46.9 HIP 99776 6.56
2026-02-22 00:00 20:15:58.15 -70:37:56.1 HIP 99776 7.12
2026-02-22 12:00 20:16:05.71 -70:38:05.6 HIP 99776 7.69
2026-02-23 00:00 20:16:13.23 -70:38:15.4 HIP 99776 8.27
2026-02-23 12:00 20:16:20.72 -70:38:25.4 HIP 99776 8.85
2026-02-24 00:00 20:16:28.17 -70:38:35.7 HIP 99776 9.43