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C/1939 H1 (Jurlof-Achmarof-Hassel)

メタデータ

項目
Designation C/1939 H1 (Jurlof-Achmarof-Hassel)
Type C
Perihelion (tp_cal, UTC) 1939-04-10T02:44:02.135040Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:29:05Z
Obs used 14
NEO -
M1 6.000
K1 4.500
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 1939-05-07.0000000
e 0.99150316
q (au) 0.528255
a (au) 62.170794
i (deg) 138.167852
Ω (om, deg) 312.348989
ω (w, deg) 89.151721
M (ma, deg) 0.054057

等級

C/1939 H1 (Jurlof-Achmarof-Hassel) · Magnitude (Full range)

散乱 + 全体線形

$$ M_a = (5.872 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 5.872
n 2.000
gf 0.800
gb -0.500
k 0.965
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

天体暦

Date/Time (UTC) RA (J2000) Dec (J2000) Nearest HIP Dist from HIP (arcmin)
2026-02-03 00:00 03:50:30.60 -22:41:27.1 HIP 18087 20.25
2026-02-03 12:00 03:50:30.18 -22:41:14.6 HIP 18087 20.35
2026-02-04 00:00 03:50:29.77 -22:41:02.1 HIP 18087 20.45
2026-02-04 12:00 03:50:29.37 -22:40:49.5 HIP 18087 20.55
2026-02-05 00:00 03:50:28.98 -22:40:36.8 HIP 18087 20.65
2026-02-05 12:00 03:50:28.61 -22:40:24.1 HIP 18087 20.75
2026-02-06 00:00 03:50:28.25 -22:40:11.3 HIP 18087 20.84
2026-02-06 12:00 03:50:27.90 -22:39:58.4 HIP 18087 20.94
2026-02-07 00:00 03:50:27.56 -22:39:45.5 HIP 18087 21.03
2026-02-07 12:00 03:50:27.24 -22:39:32.6 HIP 18087 21.13
2026-02-08 00:00 03:50:26.92 -22:39:19.6 HIP 18087 21.22
2026-02-08 12:00 03:50:26.62 -22:39:06.6 HIP 18087 21.32
2026-02-09 00:00 03:50:26.34 -22:38:53.5 HIP 18087 21.41
2026-02-09 12:00 03:50:26.06 -22:38:40.4 HIP 18087 21.50
2026-02-10 00:00 03:50:25.80 -22:38:27.2 HIP 18087 21.59
2026-02-10 12:00 03:50:25.55 -22:38:13.9 HIP 18087 21.68
2026-02-11 00:00 03:50:25.32 -22:38:00.7 HIP 18087 21.77
2026-02-11 12:00 03:50:25.09 -22:37:47.4 HIP 18087 21.86
2026-02-12 00:00 03:50:24.88 -22:37:34.0 HIP 18087 21.95
2026-02-12 12:00 03:50:24.68 -22:37:20.6 HIP 18087 22.03
2026-02-13 00:00 03:50:24.50 -22:37:07.2 HIP 18087 22.12
2026-02-13 12:00 03:50:24.32 -22:36:53.7 HIP 18087 22.21
2026-02-14 00:00 03:50:24.16 -22:36:40.2 HIP 18087 22.29
2026-02-14 12:00 03:50:24.02 -22:36:26.6 HIP 18087 22.38
2026-02-15 00:00 03:50:23.88 -22:36:13.0 HIP 18087 22.46
2026-02-15 12:00 03:50:23.76 -22:35:59.4 HIP 18087 22.54
2026-02-16 00:00 03:50:23.65 -22:35:45.8 HIP 18087 22.63
2026-02-16 12:00 03:50:23.55 -22:35:32.1 HIP 18087 22.71
2026-02-17 00:00 03:50:23.47 -22:35:18.4 HIP 18087 22.79
2026-02-17 12:00 03:50:23.40 -22:35:04.6 HIP 18087 22.87
2026-02-18 00:00 03:50:23.34 -22:34:50.8 HIP 18087 22.95
2026-02-18 12:00 03:50:23.29 -22:34:37.0 HIP 18087 23.03
2026-02-19 00:00 03:50:23.26 -22:34:23.2 HIP 18087 23.11
2026-02-19 12:00 03:50:23.24 -22:34:09.3 HIP 18087 23.18
2026-02-20 00:00 03:50:23.23 -22:33:55.5 HIP 18087 23.26
2026-02-20 12:00 03:50:23.23 -22:33:41.6 HIP 18087 23.34
2026-02-21 00:00 03:50:23.25 -22:33:27.6 HIP 18087 23.41
2026-02-21 12:00 03:50:23.28 -22:33:13.7 HIP 18087 23.49
2026-02-22 00:00 03:50:23.32 -22:32:59.7 HIP 18087 23.56
2026-02-22 12:00 03:50:23.38 -22:32:45.7 HIP 18087 23.64
2026-02-23 00:00 03:50:23.45 -22:32:31.7 HIP 18087 23.71
2026-02-23 12:00 03:50:23.53 -22:32:17.7 HIP 18087 23.79
2026-02-24 00:00 03:50:23.62 -22:32:03.7 HIP 18087 23.86