Comet Archive

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C/1975 V2 (Bradfield)

メタデータ

項目
Designation C/1975 V2 (Bradfield)
Type C
Perihelion (tp_cal, UTC) 1975-12-21T04:20:57.010560Z
Orbit solution date (soln_date, UTC) 2021-04-15T23:29:24Z
Obs used 81
NEO -
M1 10.400
K1 16.500
PC -
オスキュレーティング軌道要素
項目
Epoch (epoch_cal, TDB) 1975-12-22.0000000
e 1.00001538
q (au) 0.218721
a (au) -14217.185675
i (deg) 70.626160
Ω (om, deg) 271.312759
ω (w, deg) 358.089866
M (ma, deg) 0.000000

等級

C/1975 V2 (Bradfield) · Magnitude (Full range)

C/1975 V2 (Bradfield) · Magnitude (Highlight period)

散乱 + 全体線形

$$ M_a = (9.332 + 3.967\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta $$ $$ \theta = 180^\circ - \alpha $$ $$ \Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b) $$ $$ \Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1 $$

モデル定数

項目
H0 9.332
n 3.967
gf 0.800
gb -0.640
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 05:50:44.73 +30:57:16.6 HIP 27582 7.46
2026-02-03 12:00 05:50:43.43 +30:57:13.8 HIP 27582 7.37
2026-02-04 00:00 05:50:42.15 +30:57:11.1 HIP 27582 7.30
2026-02-04 12:00 05:50:40.87 +30:57:08.3 HIP 27582 7.25
2026-02-05 00:00 05:50:39.62 +30:57:05.6 HIP 27582 7.20
2026-02-05 12:00 05:50:38.37 +30:57:02.8 HIP 27582 7.16
2026-02-06 00:00 05:50:37.13 +30:57:00.0 HIP 27582 7.14
2026-02-06 12:00 05:50:35.91 +30:56:57.2 HIP 27582 7.12
2026-02-07 00:00 05:50:34.70 +30:56:54.3 HIP 27582 7.12
2026-02-07 12:00 05:50:33.50 +30:56:51.5 HIP 27582 7.12
2026-02-08 00:00 05:50:32.32 +30:56:48.6 HIP 27582 7.14
2026-02-08 12:00 05:50:31.15 +30:56:45.7 HIP 27582 7.17
2026-02-09 00:00 05:50:29.99 +30:56:42.9 HIP 27582 7.20
2026-02-09 12:00 05:50:28.85 +30:56:39.9 HIP 27582 7.25
2026-02-10 00:00 05:50:27.71 +30:56:37.0 HIP 27582 7.30
2026-02-10 12:00 05:50:26.59 +30:56:34.1 HIP 27582 7.36
2026-02-11 00:00 05:50:25.49 +30:56:31.1 HIP 27582 7.43
2026-02-11 12:00 05:50:24.40 +30:56:28.2 HIP 27582 7.50
2026-02-12 00:00 05:50:23.32 +30:56:25.2 HIP 27582 7.59
2026-02-12 12:00 05:50:22.25 +30:56:22.2 HIP 27582 7.67
2026-02-13 00:00 05:50:21.20 +30:56:19.2 HIP 27582 7.77
2026-02-13 12:00 05:50:20.16 +30:56:16.2 HIP 27582 7.87
2026-02-14 00:00 05:50:19.14 +30:56:13.2 HIP 27582 7.97
2026-02-14 12:00 05:50:18.13 +30:56:10.1 HIP 27582 8.08
2026-02-15 00:00 05:50:17.13 +30:56:07.1 HIP 27582 8.19
2026-02-15 12:00 05:50:16.15 +30:56:04.0 HIP 27582 8.31
2026-02-16 00:00 05:50:15.18 +30:56:01.0 HIP 27582 8.42
2026-02-16 12:00 05:50:14.23 +30:55:57.9 HIP 27582 8.54
2026-02-17 00:00 05:50:13.29 +30:55:54.8 HIP 27582 8.67
2026-02-17 12:00 05:50:12.36 +30:55:51.7 HIP 27582 8.79
2026-02-18 00:00 05:50:11.45 +30:55:48.6 HIP 27582 8.92
2026-02-18 12:00 05:50:10.56 +30:55:45.5 HIP 27582 9.05
2026-02-19 00:00 05:50:09.67 +30:55:42.3 HIP 27582 9.18
2026-02-19 12:00 05:50:08.81 +30:55:39.2 HIP 27582 9.31
2026-02-20 00:00 05:50:07.95 +30:55:36.1 HIP 27582 9.44
2026-02-20 12:00 05:50:07.12 +30:55:32.9 HIP 27582 9.58
2026-02-21 00:00 05:50:06.29 +30:55:29.7 HIP 27582 9.71
2026-02-21 12:00 05:50:05.48 +30:55:26.6 HIP 27582 9.84
2026-02-22 00:00 05:50:04.69 +30:55:23.4 HIP 27582 9.97
2026-02-22 12:00 05:50:03.91 +30:55:20.2 HIP 27582 10.11
2026-02-23 00:00 05:50:03.15 +30:55:17.0 HIP 27582 10.24
2026-02-23 12:00 05:50:02.40 +30:55:13.8 HIP 27582 10.37
2026-02-24 00:00 05:50:01.67 +30:55:10.6 HIP 27582 10.50