C/2008 C1 (Chen-Gao)

メタデータ

項目
Designation C/2008 C1 (Chen-Gao)
Type C
Perihelion (tp_cal, UTC) 2008-04-16T20:25:39.135360Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:31:16Z
Obs used 754
NEO -
M1 13.800
K1 5.250
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2008-03-06.0000000
e 1.00000066
q (au) 1.262346
a (au) -1909647.271764
i (deg) 61.784520
Ω (om, deg) 307.782377
ω (w, deg) 180.928392
M (ma, deg) -0.000000

等級

C/2008 C1 (Chen-Gao) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (12.986 + 2.066\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 12.986
n 2.066
gf 0.999
gb -0.998
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
2008-01-30 2008-04-16 +12.3117 -3.108

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)
2026-05-12 00:00 20:24:45.87 -37:40:55.3 HIP 100584 15.47
2026-05-12 12:00 20:24:44.79 -37:41:10.7 HIP 100584 15.50
2026-05-13 00:00 20:24:43.67 -37:41:26.2 HIP 100584 15.54
2026-05-13 12:00 20:24:42.52 -37:41:41.7 HIP 100584 15.58
2026-05-14 00:00 20:24:41.34 -37:41:57.3 HIP 100584 15.62
2026-05-14 12:00 20:24:40.13 -37:42:12.9 HIP 100584 15.67
2026-05-15 00:00 20:24:38.89 -37:42:28.6 HIP 100584 15.72
2026-05-15 12:00 20:24:37.61 -37:42:44.3 HIP 100584 15.78
2026-05-16 00:00 20:24:36.30 -37:43:00.1 HIP 100584 15.84
2026-05-16 12:00 20:24:34.96 -37:43:15.9 HIP 100584 15.91
2026-05-17 00:00 20:24:33.59 -37:43:31.7 HIP 100584 15.98
2026-05-17 12:00 20:24:32.19 -37:43:47.6 HIP 100584 16.06
2026-05-18 00:00 20:24:30.76 -37:44:03.5 HIP 100584 16.15
2026-05-18 12:00 20:24:29.29 -37:44:19.5 HIP 100584 16.24
2026-05-19 00:00 20:24:27.79 -37:44:35.5 HIP 100584 16.34
2026-05-19 12:00 20:24:26.27 -37:44:51.5 HIP 100584 16.45
2026-05-20 00:00 20:24:24.71 -37:45:07.6 HIP 100584 16.56
2026-05-20 12:00 20:24:23.12 -37:45:23.7 HIP 100584 16.68
2026-05-21 00:00 20:24:21.50 -37:45:39.8 HIP 100584 16.81
2026-05-21 12:00 20:24:19.85 -37:45:56.0 HIP 100584 16.95
2026-05-22 00:00 20:24:18.17 -37:46:12.1 HIP 100584 17.09
2026-05-22 12:00 20:24:16.46 -37:46:28.3 HIP 100584 17.24
2026-05-23 00:00 20:24:14.72 -37:46:44.6 HIP 100584 17.40
2026-05-23 12:00 20:24:12.95 -37:47:00.8 HIP 100584 17.57
2026-05-24 00:00 20:24:11.15 -37:47:17.1 HIP 100584 17.75
2026-05-24 12:00 20:24:09.33 -37:47:33.3 HIP 100584 17.93
2026-05-25 00:00 20:24:07.47 -37:47:49.6 HIP 100584 18.13
2026-05-25 12:00 20:24:05.58 -37:48:06.0 HIP 100584 18.33
2026-05-26 00:00 20:24:03.66 -37:48:22.3 HIP 100584 18.54
2026-05-26 12:00 20:24:01.72 -37:48:38.6 HIP 100584 18.76
2026-05-27 00:00 20:23:59.74 -37:48:55.0 HIP 100584 18.99
2026-05-27 12:00 20:23:57.74 -37:49:11.4 HIP 100584 19.23
2026-05-28 00:00 20:23:55.71 -37:49:27.7 HIP 100584 19.48
2026-05-28 12:00 20:23:53.65 -37:49:44.1 HIP 100584 19.73
2026-05-29 00:00 20:23:51.56 -37:50:00.5 HIP 100584 20.00
2026-05-29 12:00 20:23:49.44 -37:50:16.9 HIP 100584 20.27
2026-05-30 00:00 20:23:47.30 -37:50:33.3 HIP 100584 20.55
2026-05-30 12:00 20:23:45.12 -37:50:49.7 HIP 100584 20.84
2026-05-31 00:00 20:23:42.92 -37:51:06.1 HIP 100584 21.14
2026-05-31 12:00 20:23:40.70 -37:51:22.5 HIP 100584 21.45
2026-06-01 00:00 20:23:38.44 -37:51:38.9 HIP 100584 21.77
2026-06-01 12:00 20:23:36.16 -37:51:55.2 HIP 100584 22.09
2026-06-02 00:00 20:23:33.85 -37:52:11.6 HIP 100433 22.05