Comet Archive

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C/1940 R2 (Cunningham)

メタデータ

項目
Designation C/1940 R2 (Cunningham)
Type C
Perihelion (tp_cal, UTC) 1941-01-16T05:36:57.600000Z
Orbit solution date (soln_date, UTC) -
Obs used 189
NEO -
M1 -
K1 -
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 1941-01-06.0000000
e 1.00048500
q (au) 0.367751
a (au) -758.249484
i (deg) 49.894200
Ω (om, deg) 296.590500
ω (w, deg) 199.569000
M (ma, deg) -0.000483

等級

C/1940 R2 (Cunningham) · Magnitude (Full range)

C/1940 R2 (Cunningham) · Magnitude (Highlight period)

散乱 + 全体線形

$$ M_a = (5.846 + 2.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 5.846
n 2.000
gf 0.800
gb -0.500
k 1.000
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 20:19:59.83 -09:42:46.9 HIP 100138 20.50
2026-02-03 12:00 20:20:00.88 -09:42:42.7 HIP 100138 20.75
2026-02-04 00:00 20:20:01.93 -09:42:38.5 HIP 100138 21.01
2026-02-04 12:00 20:20:02.98 -09:42:34.3 HIP 100138 21.27
2026-02-05 00:00 20:20:04.02 -09:42:30.0 HIP 100138 21.53
2026-02-05 12:00 20:20:05.06 -09:42:25.8 HIP 100138 21.79
2026-02-06 00:00 20:20:06.10 -09:42:21.5 HIP 100138 22.05
2026-02-06 12:00 20:20:07.14 -09:42:17.2 HIP 100138 22.31
2026-02-07 00:00 20:20:08.17 -09:42:12.8 HIP 100138 22.56
2026-02-07 12:00 20:20:09.21 -09:42:08.5 HIP 100138 22.82
2026-02-08 00:00 20:20:10.24 -09:42:04.2 HIP 100138 23.08
2026-02-08 12:00 20:20:11.26 -09:41:59.8 HIP 100138 23.34
2026-02-09 00:00 20:20:12.29 -09:41:55.4 HIP 100138 23.59
2026-02-09 12:00 20:20:13.31 -09:41:51.0 HIP 100138 23.85
2026-02-10 00:00 20:20:14.33 -09:41:46.6 HIP 100138 24.11
2026-02-10 12:00 20:20:15.35 -09:41:42.2 HIP 100138 24.36
2026-02-11 00:00 20:20:16.36 -09:41:37.8 HIP 100138 24.62
2026-02-11 12:00 20:20:17.37 -09:41:33.3 HIP 100138 24.87
2026-02-12 00:00 20:20:18.38 -09:41:28.9 HIP 100138 25.13
2026-02-12 12:00 20:20:19.39 -09:41:24.4 HIP 100138 25.38
2026-02-13 00:00 20:20:20.39 -09:41:19.9 HIP 100138 25.63
2026-02-13 12:00 20:20:21.39 -09:41:15.4 HIP 100138 25.89
2026-02-14 00:00 20:20:22.38 -09:41:10.9 HIP 100138 26.14
2026-02-14 12:00 20:20:23.37 -09:41:06.4 HIP 100138 26.39
2026-02-15 00:00 20:20:24.36 -09:41:01.9 HIP 100138 26.64
2026-02-15 12:00 20:20:25.35 -09:40:57.3 HIP 100138 26.89
2026-02-16 00:00 20:20:26.33 -09:40:52.8 HIP 100138 27.14
2026-02-16 12:00 20:20:27.30 -09:40:48.2 HIP 100138 27.39
2026-02-17 00:00 20:20:28.28 -09:40:43.7 HIP 100138 27.64
2026-02-17 12:00 20:20:29.25 -09:40:39.1 HIP 100138 27.89
2026-02-18 00:00 20:20:30.21 -09:40:34.5 HIP 100138 28.13
2026-02-18 12:00 20:20:31.17 -09:40:29.9 HIP 100138 28.38
2026-02-19 00:00 20:20:32.13 -09:40:25.3 HIP 100138 28.63
2026-02-19 12:00 20:20:33.08 -09:40:20.7 HIP 100138 28.87
2026-02-20 00:00 20:20:34.03 -09:40:16.1 HIP 100138 29.11
2026-02-20 12:00 20:20:34.98 -09:40:11.5 HIP 100138 29.36
2026-02-21 00:00 20:20:35.91 -09:40:06.8 HIP 100138 29.60
2026-02-21 12:00 20:20:36.85 -09:40:02.2 HIP 100138 29.84
2026-02-22 00:00 20:20:37.78 -09:39:57.6 HIP 100138 30.08
2026-02-22 12:00 20:20:38.71 -09:39:52.9 HIP 100138 30.32
2026-02-23 00:00 20:20:39.63 -09:39:48.3 HIP 100138 30.56
2026-02-23 12:00 20:20:40.54 -09:39:43.6 HIP 100138 30.79
2026-02-24 00:00 20:20:41.46 -09:39:39.0 HIP 100138 31.03