Comet Archive

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C/2009 G1 (STEREO)

メタデータ

項目
Designation C/2009 G1 (STEREO)
Type C
Perihelion (tp_cal, UTC) 2009-04-16T12:08:09.119040Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:31:30Z
Obs used 119
NEO -
M1 9.100
K1 17.250
PC 0.030
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 2009-05-09.0000000
e 0.99767848
q (au) 1.128742
a (au) 486.208569
i (deg) 108.310256
Ω (om, deg) 120.634994
ω (w, deg) 175.444080
M (ma, deg) 0.002068

等級

C/2009 G1 (STEREO) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (9.287 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 9.287
n 2.000
gf 1.000
gb -1.000
k 0.965
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 08:20:05.92 -05:10:33.5 HIP 40859 9.63
2026-02-03 12:00 08:20:02.58 -05:10:16.6 HIP 40859 10.17
2026-02-04 00:00 08:19:59.24 -05:09:59.4 HIP 40859 10.75
2026-02-04 12:00 08:19:55.92 -05:09:42.1 HIP 40859 11.37
2026-02-05 00:00 08:19:52.60 -05:09:24.7 HIP 40859 12.03
2026-02-05 12:00 08:19:49.28 -05:09:07.1 HIP 40859 12.71
2026-02-06 00:00 08:19:45.98 -05:08:49.3 HIP 40859 13.42
2026-02-06 12:00 08:19:42.68 -05:08:31.4 HIP 40859 14.14
2026-02-07 00:00 08:19:39.39 -05:08:13.3 HIP 40859 14.89
2026-02-07 12:00 08:19:36.10 -05:07:55.0 HIP 40859 15.64
2026-02-08 00:00 08:19:32.83 -05:07:36.6 HIP 40859 16.41
2026-02-08 12:00 08:19:29.57 -05:07:18.0 HIP 40859 17.19
2026-02-09 00:00 08:19:26.31 -05:06:59.3 HIP 40859 17.98
2026-02-09 12:00 08:19:23.06 -05:06:40.4 HIP 40859 18.77
2026-02-10 00:00 08:19:19.83 -05:06:21.4 HIP 40859 19.57
2026-02-10 12:00 08:19:16.60 -05:06:02.3 HIP 40859 20.38
2026-02-11 00:00 08:19:13.38 -05:05:43.0 HIP 40859 21.19
2026-02-11 12:00 08:19:10.18 -05:05:23.5 HIP 40859 22.00
2026-02-12 00:00 08:19:06.98 -05:05:03.9 HIP 40859 22.82
2026-02-12 12:00 08:19:03.80 -05:04:44.2 HIP 40859 23.64
2026-02-13 00:00 08:19:00.63 -05:04:24.3 HIP 40859 24.46
2026-02-13 12:00 08:18:57.46 -05:04:04.3 HIP 40859 25.28
2026-02-14 00:00 08:18:54.31 -05:03:44.1 HIP 40859 26.11
2026-02-14 12:00 08:18:51.18 -05:03:23.8 HIP 40859 26.93
2026-02-15 00:00 08:18:48.05 -05:03:03.4 HIP 40859 27.76
2026-02-15 12:00 08:18:44.94 -05:02:42.8 HIP 40859 28.59
2026-02-16 00:00 08:18:41.84 -05:02:22.1 HIP 40592 29.18
2026-02-16 12:00 08:18:38.75 -05:02:01.3 HIP 40592 28.86
2026-02-17 00:00 08:18:35.67 -05:01:40.3 HIP 40592 28.56
2026-02-17 12:00 08:18:32.61 -05:01:19.3 HIP 40592 28.29
2026-02-18 00:00 08:18:29.57 -05:00:58.1 HIP 40592 28.05
2026-02-18 12:00 08:18:26.53 -05:00:36.7 HIP 40592 27.84
2026-02-19 00:00 08:18:23.52 -05:00:15.3 HIP 40592 27.65
2026-02-19 12:00 08:18:20.51 -04:59:53.7 HIP 40592 27.49
2026-02-20 00:00 08:18:17.52 -04:59:32.1 HIP 40592 27.36
2026-02-20 12:00 08:18:14.55 -04:59:10.3 HIP 40592 27.25
2026-02-21 00:00 08:18:11.59 -04:58:48.4 HIP 40592 27.18
2026-02-21 12:00 08:18:08.65 -04:58:26.3 HIP 40592 27.13
2026-02-22 00:00 08:18:05.72 -04:58:04.2 HIP 40592 27.11
2026-02-22 12:00 08:18:02.81 -04:57:42.0 HIP 40592 27.12
2026-02-23 00:00 08:17:59.92 -04:57:19.6 HIP 40592 27.16
2026-02-23 12:00 08:17:57.04 -04:56:57.2 HIP 40592 27.22
2026-02-24 00:00 08:17:54.18 -04:56:34.7 HIP 40592 27.31